Patent Application
20110133494
This invention relates to tools for securing a closed door, and in particular a security tool for holding a door closed in emergency applications.
Hinged doors can often be breached by an application of physical force directly to the door adjacent the door knob and lock mechanisms. A strong kick can deform the door or door frame enough to defeat the door's locking mechanism or cause damage to the door frame to such a degree that the mechanism is destroyed or fails.
Heretofore, a variety of reinforcing security prop bars have been developed to prevent hinged doors from being breached by the application of force. These prop bars simply abut against the doors to hold them closed. Much like a simple door wedge, security prop bars depend on the holding force of the prop or bar against the floor behind the door. Many security prop bars use special brackets permanently secured to the floor. Others rely on friction to provide their holding force. While conventional security prop bars are generally effective at preventing hinged doors, which open inward toward the occupant's side of the doorway, from being breached by physical force, they have several practical drawbacks. First, the door must swing inward toward the occupant; if it swings outward away from the occupant, a barricading wedge or bar cannot function because the opening motion is away from the barricading device. Second, mounting brackets to the floor is often impractical and undesirable. Conveniently storing the prop bars for rapid deployment can be an issue in many applications. Most of all, the time it takes to retrieve and deployment of the heavy prop bars from their storage location under the stress of an emergency situation can make their use impractical.
The present invention provides a tool for securing a closed swinging “push” door against opening away from the occupant under the application of physical force. The door lock tool includes a hook and a length of braided nylon webbing, which is adjustably connected to the hook. The hook has a generally J-shaped body which includes a flat back part that curves into a relatively short perpendicular leg part. A flat tooth extends perpendicularly from the hook's leg. One end of the strap is configured to form a loop for securing the strap to a door knob. The other end is laced through an opening in the hook and around a cross bar so that pulling the free end of the strap tightens the strap to close the loop and shorten the length of strap between the loop and the hook.
The door lock tool is used to secure a closed outward swing “push” door by initially placing the looped end of the strap around the door knob. Once the loop is wrapped around the door knob, the hook is positioned to catch the end of the door jam or door casing and the free end of the strap is pulled tight. As the strap is pulled tight to shorten the length of strap between the loop and the hook, the tooth bites into or under the end of the door jam or casing to secure the door. With the door lock tool so fitted to a closed outward swinging “push” door, the door cannot be forced open from either side. The outward force caused by physically pulling on the door on the other side of the secured door is retarded by the tensile strength of the braided nylon web and perpendicular holding force created by the engagement between the hook and the door jam.
The door lock tool embodying this invention can be reliably used to secure a swinging “push” door closed and prevent it from being forceably opened. The door lock tool is compact for convenient storage. The hook and strap configuration makes the tool simple and fast to employ and can be used on any door that has a conventional door knob.
Other advantages will become apparent upon a reading of the following description.
The preferred embodiments of the invention have been depicted for illustrative purposes only wherein:
Referring now to the drawings,
One skilled in the art will note several advantages of this invention over conventional door prop bars. The door lock tool embodying this invention can be reliably used to secure a closed swinging “push” door and prevent it from being forceably opened. The door lock tool is compact for convenient storage. The hook and strap configuration makes the tool simple and fast to employ and can be used on any swinging “push” door having a conventional door knob. Because of its compact size and the convenience of its use, the door lock tool of this invention is ideally suited for emergency applications, such as home invasion or active shooter situations, where the tool can be used to physically secure an outward swinging “push” door from opening.
The preferred embodiment herein described is not intended to be exhaustive or to limit the invention to the precise form disclosed. It is chosen and described to explain the invention so that others skilled in the art might utilize its teachings. It is understood that the above description does not limit the invention to the details given, but may be modified within the scope of the following claims.
