Abstract: A magnetic sleeve includes a body and a magnetic unit disposed in a second section of the body where a locking socket and a mounting hole are formed and communicating with each other. The mounting hole is enclosed by a peripheral wall while taking a reference point as center. The peripheral wall includes at least one engagement surface and at least one curved wall surface. Each engagement surface has two transition points for meeting the wall surface. The formation of one engagement surface or more engagement surfaces not only attains a firm engagement between the magnetic unit and the mounting hole but also forms a space therebetween to discharge air from the mounting hole smoothly, thereby preventing the magnetic unit from being broken during the installation. The space is also minimized to avoid undue accumulation of metal chips and allow the magnetic unit to be held in position stably.

Abstract: A magnetic sleeve includes a body and a magnetic unit disposed in a second section of the body where a locking socket and a mounting hole are formed and communicating with each other. The mounting hole is enclosed by a peripheral wall while taking a reference point as center. The peripheral wall includes at least one engagement surface and at least one curved wall surface. Each engagement surface has two transition points for meeting the wall surface. The formation of one engagement surface or more engagement surfaces not only attains a firm engagement between the magnetic unit and the mounting hole but also forms a space therebetween to discharge air from the mounting hole smoothly, thereby preventing the magnetic unit from being broken during the installation. The space is also minimized to avoid undue accumulation of metal chips and allow the magnetic unit to be held in position stably.

Abstract: An umbrella includes a runner slidably mounted on a central shaft to spread and collapse rib-and-stretcher units to which a canopy is mounted. Each rib-and-stretcher unit includes a support rib, a stretcher, and an extension rib. When the runner is moved from an upper position to an uppermost position, each extension rib is driven to slide outwardly relative to a corresponding support rib via a pivot connection between a corresponding stretcher and the extension rib, and a main portion of the canopy is moved together with the extension ribs to outwardly draw a central portion of the canopy, which movably surrounds the central shaft, to partially cover each support rib.