Electrically and manually key-controlled lock

A lock assembly for use on a door having an inside face and an outside face, the assembly comprising:

• a main lock housing;
• a first bolt movable in the housing between a locked position projecting from the housing and an unlocked position largely recessed in the housing;
• a double cylinder having
• an outside key-operable part exposed on the outside face of the door and rotatable by an appropriately bitted key,
• an inside part rotatable by the outside part and also rotatable independently of the outside part and having an actuator movable on rotation of either part, and
• a knob on the inside face of the door and coupled directly to the inside part;
• a gear linkage between the actuator and the first bolt and including a rack bar extending from the main housing for displacing the first bolt by means of the actuator, whereby the outside part or the knob can displace the first bolt between its positions;
• a secondary housing adjacent the lock housing;
• at least one secondary bolt displaceable between a locked and an unlocked position;
• a secondary linkage between the rack bar and the secondary bolt for displacing the secondary bolt synchronously with the first bolt;
• an actuator element coupled and movable with the linkage and extending from the lock housing to the secondary housing, the element moving relative to the secondary housing on movement of the first bolt between its positions;
• drive means including a reversible electric motor on the secondary housing connected to the element and energizable for displacing same and thereby also displacing the first bolt between its positions;
• and
• means including a key-operated switch displaceable between two positions and connected to the electric motor for energizing same in respective directions for moving the first bolt into the locked and unlocked positions.