摘要 |
A magnetic lock device comprises two parts, one of which provides the magnetic attraction (referred to as "part A") and the other of which is magnetically attracted by the part A (referred to as "part B"). The part A includes a permanent magnet having a center bore, a first ferromagnetic plate, and a nonmagnetic enclosure having a center bore aligned with the center bore of the permanent magnet for packaging the permanent magnet and first ferromagnetic plate. The part B includes a second ferromagentic plate that can engage the first ferromagnetic plate. Specifically, the nonmagnetic enclosure has a depressed surface on the side on which the second ferromagnetic plate engages the first ferromagnetic plate and which provides a sliding surface for the second ferromagnetic plate to be guided directly toward the center bores of the enclosure and permanent magnet. A magnetic gap is defined between the enclosure and permanent magnet, without or with an intervening annular backup member which is disposed between the enclosure and permanent magnet. The improvement according to the present invention provides advantages in reduced weight and simplified construction. |