US Patent 9284750 Door mortise lock

Provided is a door mortise lock that may improve product safety and user convenience by enabling a latch bolt operates to be unlocked after a dead bolt of the door mortise lock completely operates. To this end, the door mortise lock includes: a dead bolt driving unit that operates a dead bolt; a latch bolt driving unit that unlocks a latch bolt when a time interval passes after the dead bolt is unlocked by the dead bolt driving unit; and a connection unit that is disposed between the dead bolt driving unit and the latch bolt driving unit, and selectively operates the dead bolt driving unit and the latch bolt driving unit so that the dead bolt and the latch bolt are sequentially unlocked with a time interval.