| 摘要 |
PURPOSE: A safety device for a portable battery powered electric apparatus is provided to supply power to the electric circuitry and efficiently charge the battery unit while maintaining the supply of power to the apparatus. CONSTITUTION: A safety device(10) includes a battery unit(12) and two fuse means. The battery unit(12) for being supplied the charging current from a charging device(16) comprises one or more than one battery cells (13a-b) for supplying power to the electric circuitry (14) in the apparatus. A first fuse means(20) is connected between the battery cells (13a-b) of the battery unit (12) and a first terminal (24) of the apparatus (11) for receiving charging current from the charging device (16) and a second fuse means(21) is connected between the battery cells of the battery unit and a second terminal (26) of the apparatus (11) for supplying power to the electric circuitry (14) in the apparatus. The fuse means (20, 21) are operatively independent from each other, particularly in that the second fuse means (21) maintains the electric connection between the battery unit and the electric circuitry in the apparatus, even when or if the first fuse means (20) releases or opens in response to an undesired condition in the charging device. |
