Patent GB-1342395-A (GB)
Title: Magnet actuated mechanism for use with card having magnetic areas
IPC: G07C9/00
Filed: 1971-05-11
Abstract: 1342395 Locks H O BOEHME INC 11 May 1971 14282/71 Heading E2A A locking system which is adapted to be operated by keys providing different coded information, comprises a key receiving station 12 with reading means for sensing the information provided by any of the keys when presented thereto, decoding means responsive to the sensed information to provide an enabling electrical signal to control the locking system 11, and a key rejection device connected between the decoding means and the lock control for preventing its operation when one of the keys having predetermined coded information is presented at the key receiving station. The key rejecting device comprises a separate position corresponding to every key which is adapted to operate the system, and means for preparing a circuit at any position at any time independently of the other positions so that the key corresponding to any position which has been prepared cannot operate the control means when it is presented at the key receiving station. In the construction shown, the positions are provided by a matrix 25 which consists of row and column wires each crossover providing one position. The means for preparing any position is a plug, Fig. 6, which includes a diode 36 which when the plug is engaged with the matrix at any desired crossover connects the row and column wires together so preparing a circuit. The plug is engaged with the matrix by passing electrodes 34 through apertures between the conductors and rotating the plug so that hooks 35 engage one conductor and a terminal 37 of the diode engages the other conductor. A block diagram of the system is shown in Fig. 2 the key being shown as a card 42 which has magnetised areas providing the coded information and which are sensed by the reading means 43 and passed to the decoding means 44 which is connected with the rejection matrix 25 and a printer 24 for recording the key information and the time at which the key is inserted into the reader 43; the circuit 44 operates a relay 45 which in turn actuates an unlocking mechanism 11 if the key is not to be rejected by the matrix 25, if the key is to be rejected a rejecting relay 46 is operated by the circuit 44 which prevents operation of the relay 45 and hence of the unlocking mechanism 11. Two signals are also provided to indicate either that the mechanism 11 has been operated or that a key has been rejected. The part of the circuit 44 concerned with the rejection matrix 25 is shown in Fig. 7; this includes four decoders 47-50 which receive information in binary coded decimal form from the key and each provide an output signal in decimal form on one of ten lines. The decoder 48 which provides the tens digits has a respective relay 52 connected to each of its ten outputs and each relay has ten pairs of contacts, the ten pairs of contacts of each relay being connected to respective output lines of the units decoder 47, the 100 output lines provided by the contacts of the relay being connected to the individual row conductors of the matrix. Similarly, the thousands decoder 50 controls ten relays each with ten pairs of contacts which are similarly connected to the hundreds decoder 49 to provide 100 output lines which are connected to the column conductors of the matrix. Any diode plugged into the matrix completes a circuit via the decoders 47 and 49 to energise the coil of the rejecting relay 46 to operate the reject signal and to prevent operation of the relay 45. The part of the decoding circuit 44 which is concerned with providing a signal to operate the relay 45 is not described.