Electronically protected holder for small valuable items - has buzzer sounded if object e.g. credit card or passport is removed from holder sleeve for more than set period of time

摘要

The objects are installed in sleeves in the holder, which is itself fitted into a handbag or coat pocket, using buttons, clips, or 'Velcro' type material. When it is in position, the object holds apart the contacts (9,10) of a switch (22). - When it is removed from the holder, the switch connects a battery to two timing circuits (20,21). In the first circuit (20) a capacitor (C1) is charged via a resistor (R1) until after a preset period, the capacitor charge trips a level detection circuit (24) which starts an astable multivibrator (26) via a driver transistor (25). The multivibrator drives a small bleeper (23), to remind the user to replace the object. (19pp Dwg.No.1/7)