Retrofittable electronic and mechanical door lock system

Claim 1

A lock system adapted to be fitted onto conventional locks having a cylinder which turns to unlock a door, the cylinder having a slot therein, the lock system comprising portions of a device installable on a door; (a) an electronic socket adapted to read digital code from a portable electronic key means inserted therein; (b) an electronic circuit means to verify the code with code stored therein and produce a control signal upon the verification of the code the electronic circuit including a programmable microprocessor and being connected to the socket; (c) a rotary bi-directional direct current motor controlled by the electronic circuit means and having an output shaft; (d) a gear reduction system having a series of meshing gears and driven by the motor output shaft, the reduction system having a reduction ratio of at least 50:1 and having a rotatable output gear; (e) a transfer means driven by the reduction system output gear; (f) a battery connected to the motor and electronic circuit; (g) a slide means mounted for vertical sliding motion and slidable by the transfer means; (h) a projection fixed to the slide means and when the slide means is moved by the transfer means the projection is inserted into the slot of the cylinder thereby preventing the cylinder from turning and locking the door and when the slide means is again moved by the transfer means the projection is removed from the slot and thereby unlocks the door.