In general, a door is held shut by means of a latch mechanism. The latch mechanism is spring-loaded so that it automatically catches on to a recess in the door jamb when the door is closed. The latch mechanism is released by means of a handle or knob. When the handle is turned, the latch retracts from the recess in the door jamb and allows the door to be opened.
When closed, the door may be described as separating an inner enclosed area from an outer area. When closed, the door is be partially or fully surrounded by straight or curved structural elements making up the various sections of a door frame. The inner side of the door faces the inside area when the door is closed, while the outer side faces the outer area when the door is closed. Perpendicular to both the inner and outer sides of the door are edge surfaces. One edge surface abuts a door jamb when the door is closed. Other edge surfaces of the door may abut other section of a door frame. In general, door handles are provided on both sides of the door so that the door may be opened from either side. The handle on the inner side of the door may be provided with a handle locking mechanism that locks the latch inside the recess in the door jamb. In this case when the handle locking mechanism is locked, the handle on the outer side of the door cannot be used to open the door. However, simply turning the inside handle overrides the locking mechanism and permits quick exit in case of an emergency.
Where additional security against intruders is required, a door will often be provided with a bolt mechanism. In the case of a relatively simple bolt mechanism, the bolts are inserted into recesses in the door jamb or into structures attached to the door jamb. In the case of a higher security bolt mechanism, additional bolts may be inserted into structures in other parts of the doorframe. Generally, a bolt mechanism does not engage automatically upon closing the door. Rather, in order to engage the bolts, a key is inserted into a keyway and turned, or a knob or handle that is separate from the door handle is turned. In order to disengage the bolts, the key or handle is turned in the opposite direction.
An example of such a bolt mechanism is described in U.S. Pat. No. 3,991,595 (Bahry et al.). Bahry et al. describe a preferred embodiment in which a key-operated cylinder lock turns a wheel that extends four bolts by means of curved links. The bolts extend from various edge surfaces of a door.
In an emergency situation, such as a fire inside a building, it is often necessary to exit quickly. Any delay in opening and exiting through the door could result in serious injury or loss of life. Although a latch mechanism is released simply by turning the door handle, disengaging the bolt mechanism is more time consuming and requires closer attention. Should the bolt release mechanism require a key and the key has been removed form the keyway, time may be wasted in locating the key and inserting it into the keyway. Even if the key is already in the keyway, or a handle is provided for opening the bolt, a panicked individual may waste time in finding the correct direction in which to turn the key or handle. In addition, finding the key or handle on the door may be difficult should the room be dark or filled with smoke.
In WO 2006/003661 (Segev et al.) an intelligent lock was described comprising a mechanical element operative to provide two lock position upon a proper actuation, and an electromechanical (EM) trigger separate from and coupled to the mechanical element and operative to control the actuation. When included in an intelligent locking system, the lock is remotely controllable through a monitoring and control unit, operative to relay commands to the EM trigger.
It is an object of the present invention to provide a lock with a bolt mechanism that may be easily and quickly disengaged in the event of an emergency.
It is another object of the present invention to provide a lock with a bolt mechanism and a safety trigger with an emergency override mechanism.
Other objects and advantages of the present invention will become apparent after reading the present specification and reviewing the accompanying drawings.