| 摘要 |
PURPOSE:To prevent damage of a package due to an erroneous insertion by providing a protrusion and a cutout on the rear surface of a surface plate and the package, and providing switch means for turning ON, OFF a power source voltage in response to the mounting state of the plate. CONSTITUTION:When all packages 51 are mounted at correct positions in a shelf, a surface plate 3 is mounted on the shelf 11. A switch SW mounted at the lower right side of a package insertion port is pressed by the plate 3 to be closed, and connected to a power source line. On the other hand, if the partial package is mounted at an erroneous position in the shelf, the cutout 511 of the package erroneously inserted is not engaged with the protrusion 31 provided on the plate 3. Then, since the plate 3 is not mounted on the shelf 11, the switch SW is not pressed to the plate, but remains OFF. Thus, the power source voltage is not applied to all the packages. Accordingly, the packages are not damaged. |
