| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable interrupting a power source at an I/O box side simultaneously together with the isolation of a terminal equipment by interrupting the power source at the I/O box when it is detected that the terminal equipment is removed from the I/O box. SOLUTION: The power source part at the I/O box side is provided with a power source stabilizing circuit 2-8 and a power source ON/OFF part 2-9. The power source stabilizing circuit 2-8 is connected to an AC power source and a D.C. voltage is applied on the power source ON/OFF part 2-9. Then, when a portable terminal equipment is removed from the I/O box, the input/ output end of a connection detecting signal Cd is opened in the power source ON/OFF part 2-9 so that a control transistor CTr is turned off and, then, a power transistor PTr is turned off. In result, the power source at the I/O box side is automatically and simultaneously interrupted together with the isolation of the portable terminal equipment from the I/O box.</p> |
