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RELATED APPLICATIONS 
     This application claims priority from U.S. Provisional Application No. 61/811,218 filed on Apr. 12, 2013. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to an Emergency Barricade System (EBS) to protect potential victims from harm-doers. It essentially comprises a Quickly Activated Bolt Latch (QABL) and an Unlocking Tool to unlock the locked bolt latch from the exterior of the barricaded area by rescuers. The QABL is a door bolt lock system that can be hastily locked by foot in a crisis and also can be unlocked by foot without a key or without having to search for the lock. 
     BACKGROUND OF THE INVENTION 
     Tragic situations such as the school shootings in Newtown, Conn. and Columbine, Colo. have taken place over the past few years in this country. Many young lives have been lost in these tragedies because the shooter had unfettered access to his victims. In such situations, many lives would have been saved if the victims had been able to quickly and easily barricade themselves in their class-rooms or other secure areas. 
     The EBS described below provides protection to potential victims who might find themselves in a dangerous situation and need to barricade themselves from persons who may desire to do them harm. 
     SUMMARY OF THE INVENTION 
     The embodiment of the Emergency Barricade System (EBS) described herein comprises a Quickly Activated Bolt Latch (QABL) and an Unlocking Tool (UT). 
     The QABL comprises a casing with a longitudinally oriented bore which is open at least at one end. The casing has a means for attaching to a door, with the open end of the bore generally aligned with the edge of the door. A sliding element (SE) is located within the casing. The SE closely fits within the bore of the casing and has a first end and a second end. The SE is capable of being slidingly positioned within the bore in a first (disengaged) position or in a second (engaged) position. In the engaged position, the first end of the SE protrudes through the open end of the bore to engage a matching bolt-hole in the floor or door frame. During normal times, the SE is held in the disengaged position by a spring means. At times of crisis, the SE can be rapidly moved from the disengaged position to the engaged position against the action of the spring means by downwards pressure from the user&#39;s foot. The SE is held in its engaged position by a locking means. When the crisis is over, the SE is released from its engaged position by an unlocking means. When the SE is released, the spring means returns the SE to the disengaged position. 
     In the embodiment of the Emergency Barricade System (EBS) described herein, the bore of the QABL has a second open end which protrudes out of the second open end when the SE is in the disengaged position. A foot pedal is attached to the second end of the SE to move it quickly from the disengaged position to the engaged position against the action of the spring means. The spring means to hold the SE of the QABL in the disengaged position is a partially compressed helical spring positioned around the sliding element between the second open end of the bore of the casing and the foot pedal. The spring is generally fully compressed when the foot pedal is pressed. 
     In the embodiment of the Emergency Barricade System (EBS) described herein, the locking means to lock the SE in place when it is in the engaged position comprises a toggle bar and a spring which is located in a longitudinal cavity in the SE. The toggle bar is pivotingly attached at its first (lower) end within the cavity. The spring maintains the second (free) end of the toggle bar in sliding contact with the inside surface of the bore. The bore has an engaging surface to hold the toggle bar in a swung out position to arrest the SE in an engaged position and prevent the spring means from returning the SE to the disengaged position. 
     Further in the embodiment of the Emergency Barricade System (EBS) described herein, the unlocking means to unlock the SE from the engaged position comprises a release pin which is located in a pin-hole in the casing of the QABL. The pin-hole is located over the free end of the toggle bar when the SE is in an engaged position. The release pin slidingly fits and partially protrudes out of the pin-hole in the casing. When the protruding end of the pin is pressed, the pin pushes the second end of the toggle bar past the engaging surface within the bore to release the SE from its engaged position. A spring means is provided to return the release pin to its partially protruding position within the pin-hole in the casing after it has been pressed to release the SE of the QABL from its engaged position. As an option, a toggle lever is provided in contact with the protruding end of the release pin to facilitate the pressing of the release pin. 
     The EBS described herein further comprises an Unlocking Tool (UT) means to unlock the QABL from outside the room. The UT means is configured as a flat bar having a crook at its insertion end to engage the unlocking means of the QABL. The flat bar is thin enough to be inserted in the gap between the closed door and the doorframe or floor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a plan-view representation of the Quickly Activated Bolt Latch (QABL) in a disengaged position. 
         FIG. 1B  is a plan-view representation of the QABL in an engaged position. 
         FIG. 1C  is an end-view representation of the QABL. 
         FIG. 2A  is a cross-sectional view representation of the QABL in a disengaged position. 
         FIG. 2B  is a cross-sectional view representation of the QABL in an engaged position. 
         FIG. 3  is a three-dimensional exploded view representation of part of the QABL showing the internal details of the locking mechanism. 
         FIG. 4  is a cross-sectional view representation of the QABL with a toggle-lever to facilitate the operation of the unlocking mechanism. 
         FIG. 5  is a representation of the Unlocking Tool (UT) for unlocking the QABL from outside the room. 
     
    
    
     DETAILED DESCRIPTION 
     The Emergency Barricade System (EBS) described herein comprises a Quickly Activated Bolt Latch (QABL)  100  and an Unlocking Tool  200  to unlock the bolt latch from the exterior of the barricaded area by rescuers. The QABL can be quickly and easily activated to safeguard persons who are in a potentially threatened position. 
       FIGS. 1A, 1B, 1C, 2A, 2B, and 3  represent an embodiment of the Quickly Activated Bolt Latch (QABL)  100 , which is disclosed herein. 
     QABL  100  comprises a casing  110  with a longitudinally oriented cylindrical bore  114  through which a sliding element shown as bolt  120  (described further below) is located. Further, casing  110  has a means, which is shown in  FIG. 1A  as base  112  with mounting holes  112   h , to attach the casing to a door. Base  112  can be attached to a door with screws through mounting holes  112   h . Ideally, casing  110  is attached to the lower edge of the door. In this position, bolt  120  engages a mating bolt-hole located in the floor or door-frame when the lower portion of bolt  120  is slid out of casing  110  (as described further below). This action secures the door firmly in a closed position 
     Bore  114  is generally cylindrical throughout its length except that it has an internal longitudinally oriented square or rectangular cross-sectioned slot  115  (see  FIGS. 2A, 2B, and 3 ) in its lower section to accommodate a locking means for locking the bolt  120  in the engaged position with the bolt-hole. The locking means is shown as catch mechanism  124  (described below) on bolt  120 . Slot  115  also creates step  115   s  within bore  114  which engages catch mechanism  124  as will be described below. Slot  115  is created by machining a square or rectangular channel of desired length longitudinally within the inside cylindrical surface of the lower section of bore  114 . 
     Further, an unlocking means  116  is provided on casing  114 . The unlocking means comprises a cylindrical pin-hole  116   h  in casing  110  and release pin  116   p . Cylindrical pin-hole  116   h  is provided at a generally perpendicular orientation to slot  115  of casing  110 . Pin-hole  116   h  is designed to contain release pin  116   s , which will be described below. 
     Bolt  120  is a cylindrical member about 0.75 inch in diameter and about 7 inches long which slidingly fits within bore  114 . Groove  120   g  (see  FIGS. 2A and 2B ) is provided in the lower section of bolt  120  to house catch mechanism  124 . Catch mechanism  124  comprises a toggle-bar  124   r  which is pivotingly attached at its first end  124   r   1  within groove  120   g  by pin  124   p . Spring  124   s  is provided to bias second end  124   r   2  of toggle-bar  124   r  outwards from groove  120   g . Thus toggle-bar  124   r  pivots around pin  124   p  and normally is biased such that its second (free) end  124   r   2  swings out of groove  120   g  until it is mechanically forced back into groove  120   g.    
     A foot pedal  125  is attached to the upper end  120   u  of bolt  120 . To keep bolt  120  in a normally disengaged position, helical spring  122  is provided around bolt  120  between foot pedal  125  and casing  110 . In the uncompressed position, spring  122  pushes bolt  120  upwards to its normally disengaged position as shown in  FIGS. 1A and 2A . When foot pedal  125  is pressed down, bolt  120  is pushed down further into bore  114  such that its lower end  120   a  extends out of casing  110  to engage the bolt-hole as shown in  FIG. 2B . 
     To operate QABL  100 , the door is closed so that bolt  120  is located over the bolt-hole. Bolt  120  of QABL  100  is now in the disengaged position shown in  FIGS. 1A and 2A . The user then presses foot pedal  125  using his/her foot to move foot pedal  125  and attached bolt  120  towards the bolt-hole against the reactive force of spring  122  which is now compressed as shown in  FIGS. 1B and 2B . The relative lengths and positions of slots  115  and toggle-bar  124   r  are designed such that when lower end  120   a  of bolt  120  is sufficiently inserted (e.g. 2.5 inches) into the bolt-hole, toggle-bar  124   r  is automatically released from its confined position (shown in  FIGS. 1A and 2A ) within the upper cylindrical section of bore  114 . In this unconfined position (shown in  FIGS. 1B and 2B ), the free end  124   r   2  of toggle-bar  124   r  automatically swings out into slot  115  of bore  114  due to the action of spring  124   s . When the user takes his/her foot off foot pedal  125 , the reactive force of spring  122  pushes foot pedal  125  and attached bolt  120  upwards. Since toggle-bar  124   r  now is in a swung out position within slot  115  of bore  114 , it engages step  115   s  (shown in  FIGS. 1B and 2B ) of slot  115  as it moves upwards within bore  114 . Bolt  120  is thus constrained in a locked position with its lower section  120   m  embedded in the bolt-hole. The door is now secured against potential intruders. As a secondary action, when free end  124   r   2  of toggle-bar  124   r  is swung out of groove  120   g  by spring  124   s  into slot  115  of bore  114 , free end  124   r   2  of toggle-bar  124   r  also pushes out release pin  116   p  through pin-hole  116   h  to a partially protruded position. 
     When bolt  120  is to be unlocked from the bolt-hole, the user presses release pin  116   p  with his/her finger or foot. When release pin  116   p  is pressed, it pushes free end  124   r   2  of toggle-bar  124   r  away from step  115   s  of slot  115  in bore  114  back into groove  120   g  of bolt  120 . The reactive force of spring  122  pushes foot pedal  125  and attached bolt  120  upwards. Lower section  120   m  of bolt  120  is thus dis-embedded from the bolt-hole and the door can be opened. Spring  116   s  may be provided to maintain release pin  116   p  normally in a protruded state. 
     Release pin  116   p  can be pressed manually by the user from within the barricaded area to unlock QABL  100  or can be pressed from outside the room using the Unlocking Tool (described below). Since release pin  116   p  has a rather small contact area, a release lever  119  can be provided as an option (shown in  FIG. 4 ). Release lever  119  has a free end  119   f  which is in contact with protruding end  116   pe  of release pin  116   p . The second end  119   p  of release lever  119  is pivotingly attached to casing  110 . Thus release lever  119  provides a much larger contact area to facilitate unlocking QABL  100  from outside as described in the above paragraph. When free end  119   f  of release lever  119  is pressed, it presses release pin  116   p  to unlock bolt  120  from its locked position as described above. 
     QABL  100  can also be unlocked by a rescuer from outside the barricaded area by using an Unlocking Tool which is designed specifically for this purpose.  FIG. 5  shows a representation of Unlocking Tool  200  that can be used for this purpose. The tool is configured as a flat, rigid bar  200  with a handle  200   h  at its first end and a crook  200   c  at its second end. The thickness of bar  200  is designed such that it can be inserted through the gap between the door and the floor or door frame. 
     The user holds the bar by handle  200   h  and then manipulates it until end  200   ce  of crook  200   c  is positioned and contacts protruding end  116   pe  of release pin  116   p  or release lever  119  on QABL  100 . The user then pulls on handle  200   h  to press release pin  116   p  or release lever  119  to release bolt  120  from its locked position (described above) to open the door. 
     Thus QABL  100  does not need a key for it to be opened from the outside. Installation is simple as it does not require a key-hole to be drilled in the door for its operation. It can be quickly and easily installed in any door, preferably at the bottom of the door panel so that it can be quickly and easily activated by the user simply by pressing down on the foot pedal. The EBS can be operated using gross motor skills only. 
     Thus, in a potentially threatening class-room situation, a teacher can activate the bolt without taking his/her eyes off the students or off the threatening situation. Further, unlocking means  116  is simple enough that even a very young student can operate it to open the door. The QABL is ruggedly built so that it will be difficult for an intruder to physically kick in the door. Also, it will still function if the intruder fires his gun at it. The EBS can be used not only in class-rooms but in every situation where quick action is required for the potential victim to barricade himself or herself. Such situations would include airplane cockpits, offices, safe-rooms, etc. 
     The preferred embodiment of the EBS has been generally described above in a conceptual manner without detailed dimensions and other engineering data. It will be obvious that persons having ordinary skill in the art can select the design parameters to design the QABL and the Unlocking Tool of the EBS described herein for use in specific situations. 
     While preferred embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will occur to those skilled in the art without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the following claims.

Summary:
An Emergency Barricade System (EBS) to protect children in school shootings from harm-doers is disclosed. The EBS comprises a Quickly Activated Bolt Latch (QABL) and an Unlocking Tool (UT). The QABL is attached to the inside surface of a classroom door. In an emergency, the bolt of the QABL can be quickly slid into a bolt-hole by foot pressure. The bolt is held in place in the bolt-hole by a locking means in the QABL. The bolt can be easily unlocked by pressing on a release pin on the QABL. A spring is provided in the QABL to automatically return the bolt to its normal position. An Unlocking Tool is provided to enable rescuers to unlock the QABL from outside the classroom.