BACKGROUND OF THE INVENTION
The present invention relates to an electronic door lock dogging mechanism to be used with an emergency door latching system.
SUMMARY OF THE INVENTION
Emergency door latching systems are well known, such as those disclosed in U.S. Pat. Nos. 5,322,332 and 4,839,988, which disclosures are incorporated herein by reference.
As shown in FIG. 2, when a door 20 is closed and locked, a bolt 22 extends vertically through a plate 24 secured to a transom header 26. The bolt 22 also extends through a hole 28 in a trigger 30 (second mechanical element). There the trigger 30 is spring loaded and biased to the left, but is pushed to the right when the door 20 is closed, to align the hole 28 with the bolt 22. To open the door 20, pressure is applied to the door release mechanism (not illustrated), retracting the bolt 22 downwardly against the force of a spring 32 (first mechanical element). When the door 22 is open (FIG. 1), the trigger 30 is pushed to the left by a spring 34 such that the hole 28 in the trigger 30 will move to the left and will block the bolt 22 from moving upwardly (dog the bolt), even though pressure on the door release mechanism may be removed. This is shown in FIG. 1. This will allow the door 20 to swing back closed without the bolt 22 hitting the transom 26. As soon as the door 20 is nearly completely closed, a nose 36 of the trigger 30 will engage the door frame stile 38, pushing the trigger 30 to the right, and releasing the bolt 22. The bolt spring 32 will push the bolt 22 upwardly through the trigger 30 and the plate 24, into the transom 26, relocking the door 20.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 schematically illustrates a prior art construction being a cross sectional view of the door, at the top and near the free edge, and looking in the direction from the free edge towards the hinge, with the bolt in the dogged position.
FIG. 2 schematically illustrates a prior art construction being a cross sectional view of the door, at the top and near the free edge, and looking in the direction from the free edge towards the hinge, with the bolt in the extended, locking position.
FIG. 3 schematically illustrates a first embodiment of an electronic door lock dogging mechanism embodying the principles of the present invention in a cross-sectional view of the door, at the top and near the free edge, and looking in the direction from the free edge toward the hinge, with the bolt in the extended position.
FIG. 4 schematically illustrates a second embodiment of an electronic door lock dogging mechanism embodying the principles of the present invention in a partial cross- sectional view of the door frame, at the top and near the free edge of the door, and looking at the face of the closed door.
FIG. 5 schematically illustrates the second embodiment of the electronic door lock dogging mechanism of FIG. 4 in a cross-sectional view of the door, at the top and near the free edge, and looking in the direction from the free edge towards the hinge, with the bolt in the extended, locking position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As illustrated in FIG. 3, an embodiment of the present invention uses an electronic mechanism to unlock the door 20, and to allow the bolt 22 to remain in the unlocked (dogged) position, even if the door is closed. Power is provided to a solenoid 40 (first electrical element) with a vertically movable piston 41 to drive the bolt 22 vertically downwardly against its spring 32. The solenoid 40 has an actuator 42 that moves downwardly, simultaneously with movement of the solenoid piston. The solenoid actuator 42 engages a vertical arm 44 of a pivoted cam 46 (third mechanical element), causing the cam 46 to rotate, from a first position clockwise against a cam spring 48 (fourth mechanical element). A substantially horizontal arm 50 of the cam 40 is rotated upwardly to a second position into the proximity of an electro magnet 52 (second electrical element), which is energized. When the cam 46 rotates, an extending lobe 54 of the cam 46 moves away from engagement with the nose 36 of the trigger 30, allowing the trigger spring 34 to cause the trigger 30 to move to the left, once the bolt 22 has moved down. This will “misalign” the trigger hole 28 with the bolt 22, allowing the bolt to be held in the downward position (dogged), as in FIG. 1. The power to the solenoid 40 can then be removed, and only the smaller power to the electro magnet 52 will remain. The door 20, even when in the closed position, will remain unlocked, in that the nose 36 of the trigger 30 will be received in a recess 56 in the door frame stile 38 normally occupied by the cam lobe 54.
When it is desired to relock the door 20, power is removed from the electro magnet 52, and the cam 46 is rotated by cam spring 48 to press the cam lobe 54 against the nose 36 of the trigger 30, releasing the bolt 22 and allowing it to move upwardly as biased by its spring 32 into the locked position of FIG. 2.
As illustrated in FIGS. 4 and 5, a second embodiment of the present invention uses a similar electronic mechanism to unlock the door 20, and to allow the bolt 22 to remain in the unlocked (dogged) position, even if the door is closed. Power is provided to a solenoid 140 (first electrical element) to drive the bolt 22 downwardly against its spring 32. The solenoid 140 has a horizontally movable piston 141 which presses against a pivoted push arm 143 that provides a downward force on an actuator 142 carried on a vertically movable piston as the solenoid piston 141 moves outwardly relative to the solenoid 140. The actuator 142 engages a vertical arm 144 of a pivoted cam 146 (third mechanical element), causing the cam 146 to rotate, from a first position clockwise against a cam spring 148 (fourth mechanical element). A substantially horizontal arm 150 of the cam 140 is rotated upwardly to a second position into the proximity of an electro magnet 152 (second electrical element), which is energized. When the cam 140 rotates, an extending lobe 154 of the cam 140 moves away from engagement with the nose 36 of the trigger 30, allowing the trigger spring 34 to cause the trigger 30 to move to the left, once the bolt 22 has moved down. This will “misalign” the trigger hole 28 with the bolt 22, allowing the bolt to be held in the downward position (dogged), as in FIG. 1. The power to the solenoid 140 can then be removed, and only the smaller power to the electro magnet 152 will remain. When the solenoid 140 is deenergized, the piston 141 will retract and a compression spring 155 will cause the vertically movable piston 145 to move upwardly, thereby moving the actuator 142 away from the vertical arm 144 of the cam 146. The door 20, even when in the closed position, will remain unlocked, in that the nose 36 of the trigger 30 will be received in the recess in the door frame stile 38 normally occupied by the cam lobe 154.
When it is desired to relock the door 20, power is removed from the electro magnet 152, and the cam 146 is rotated to press the cam lobe 154 against the nose 36 of the trigger 30, releasing the bolt 22 and allowing it to move upwardly as biased by its spring 32 into the locked position of FIG. 2.
The various mechanical end electrical elements can be provided in other forms than those described in the particular embodiment illustrated. For example, the first mechanical element may comprise other types of springs than the compression spring illustrated, including expansion springs, hydraulic and pneumatic cylinders, and other known energy storage devices. The second mechanical element may be different than the slidable trigger illustrated, including a pivotable member, a member that engages only a portion of the bolt, rather than surrounding the bolt with a hole, a member that engages a sidewall rather than the end wall of the bolt, and other similar variations. The third mechanical element may be different than the rotatable cam illustrated, including a slidable member to engage and disengage with the second mechanical element, it may be biased with other than a compression spring, as in the first mechanical element, the arms may be configured differently than shown, or replaced altogether with other elements to effect the necessary movements and restraints. The fourth mechanical element may be different than the compression spring illustrated, including expansion springs, hydraulic and pneumatic cylinders, and other known energy storage devices. The first electrical element may be different than the solenoid illustrated, including hydraulic and pneumatic cylinders, wax motors, motor driven screws or racks and other known electrically extendable and retractable devices. The second electrical element may be different than the electro magnet illustrated, including other known electrically powered latches and catches for holding the third mechanical element. The arrangement illustrated may be applied at the top of the door as shown, and/or at the bottom of the door, or arranged at 90 degrees to the orientation illustrated to have the bolt extend essentially horizontally into the door stile or other portion of the door frame.
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceding specification and description. It should be understood that we wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of our contribution to the art.
Patent Grant
7055871
