A Tamper Protection Switch
Original Publication Date: 2001-Oct-18
Included in the Prior Art Database: 2003-Jun-20
To protect information stored in a volatile memory device from tampering or tapping, one of the most general schemes is to use a micro switch (or limit switch) such as shown in Figure 3 and 4 below. However weakness of this method is that the shape, the function and the mechanism of micro switch are well known in public. When its existence and location are identified from outside of the equipment by means of X-rays for example, it is easy to break the protection scheme: by opening a small hole in the case lid, pushing down the micro switch to normal position during complete removal of the case lid. The disclosed invention is illustrated in Fig. 1 and 2. The invented apparatus functions as a transfer switch, and consiss of (1) Normally opened contacts, (2) Nomally closed contacts, (3) Molded enclosure for the contacts, (4)insulator with conductive ring to shorten (1), and (5) Insulator to open (2). As an optional enhancement feaure, x-ray reflecting or absorbing scheme is employed for the molded enclosure (3).