US Patent 7000441 Lock cylinder assembly

The present invention relates to a lock cylinder assembly (10) comprising a cylinder housing (12); a cylinder (14); a first electromagnetic coil (48); a first locking member (52); and a key. The cylinder (14) is rotatable in the cylinder housing (12) and the first locking member (52) is urged by a first magnetic field towards a locked position in which rotation of the cylinder (14) is prevented. In use, when the first electromagnetic coil (48) is energised upon the use of the key, a second magnetic field created thereby causes the at least one locking member (52) to move out of the locked position so as to allow said cylinder (14) to be rotated in the cylinder housing (12).