Patent Publication Number: US-2007113478-A1

Title: Emergency exit security gate

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      This invention is generally directed to heavy duty open mesh gates for use with conventional emergency exit fire and/or security doors used in businesses, commercial or retail establishments and residential environments and, more specifically, to such gates that are so structured that when locked in place relative to an emergency exit opening, permit an adjacent security or emergency exit door to be opened for purposes of increasing ventilation and light entrance with respect to an enclosed area but that provide adequate security to prevent unauthorized ingress through the gate into the enclosed area.  
      2. Brief Description of the Related Art  
      Metal security and fire doors are frequently used in buildings to prevent unauthorized passage though a doorway normally because of security and ingress control concerns. Because of safety concerns, such doors are provided with special heavy duty locking mechanisms that make tampering to obtain unauthorized access to an area extremely difficult. Normally, such doors are retained shut and locked unless personal are present to ensure authorized passage through the protected openings or unless an emergency within the protected area makes exit through the protected openings necessary.  
      In some instances it may be necessary to have individuals within a protected area make emergency passage through an emergency exit. Over the years, it has been determined that conventional door locks and knobs are unsatisfactory and potentially unsafe for use with emergency exit and/or fire doors, not only for mechanical reasons, but also due to the difficulty operating such devices during an emergency, such as when there is a panic situation or when visual recognition of door locks and/or knobs is difficult or impossible. To overcome such problems, many emergency exit doors are equipped with latch release mechanisms frequently termed or called “panic bars” or “touch bars”. Such bar-like release mechanisms extend over a substantial surface area and, when forced inwardly relative to the door, create effective leverage to cause heavy duty safety latches to be readily released. Such a conventional panic bar release is disclosed in U.S. Pat. No. 5,535,550 Yang.  
      Unfortunately, most such security and fire doors function as solid barriers thereby preventing passage of light and reducing air flow circulation relative to an enclosed area. There are many instances wherein it would be advantageous to be able to open a security or fire door in order to create a more compatible, comfortable or healthy environment by allowing light to enter an enclose area or to vent the area to the ambient surroundings. By way of example, it may be beneficial or become necessary to ventilate odors, smoke and the like from an otherwise enclosed area but still provide security to prevent unauthorized entrance into a protected area to protect people, goods or other items within the area.  
     SUMMARY OF THE INVENTION  
      The present invention is directed to a unique security gate that is adapted to be easily mounted in facing relationship with substantially any type of security or fire door that utilizes a bar type operating mechanism, or “panic” or “touch” bar, for controlling the opening or release of one or more latches that normally retain the door in a closed and locked position. The security gate is constructed of steel frame components to which an expanded heavy duty metallic mesh material is welded or otherwise secured. The gate is preferably pivotally mounted to an outer steel frame that is secured to an interior wall or frame surrounding the perimeter of the exit opening normally blocked by the conventional emergency or fire door. The gate and outer frame cooperatively fit such that no large openings are created there between through which small animals can pass to obtain access through the opening into the protected area.  
      The gate carries a latch and locking assembly wherein the latch is normally engaged with a latch seat or housing in the outer frame such that the latch can not be tampered with from the outside thereof. The gate may be provided with a conventional type lock that can be opened from the outside by way or use of an appropriate and authorized key type device.  
      The gate is design to be locked with respect to the frame whenever the adjacent door is opened to thereby provide continued security with respect to a protected area but at the same time permit ventilation and passage of light through the exit opening. Should an emergency arise wherein the exit opening must be opened from the inside of the protected area, a release lever or similar equivalent structure, is engaged along the inside of the gate to release the latch associated with the locking assembly.  
      In those instances when both the emergency door and gate are in their closed and locked positions and a condition arises wherein immediate passage is required through the exit opening to permit people to egress there through, the present invention provides an engagement mechanism on an outer portion of the security gate that is designed to engage the panic or touch bar release mechanism associated with the conventional emergency or fire exit door. The engagement mechanism preferably includes a roller device that can engage with and roll along the panic or touch bar of the door lock such that the roller both depresses the bar to open the door while simultaneously traveling along the bar without any chance of binding or adverse friction being created between the roller and the panic bar. In this manner, both the gate and the fire or emergency door are simultaneously opened.  
      It is a primary object of the invention to provide a very sturdy open mesh gate that can be generally universally mounted in facing relationship with any conventional fire or emergency door having a panic or touch bar type latch or door lock release mechanism so that the operation of the latch control mechanism of the gate lock assembly will automatically unlock the latch of the door by operation of the panic bar associated therewith so that both the gate and the door are simultaneously unlocked and opened to permit emergency exit from a protected area.  
      It is a further object of the present invention to provide a security gate that can be installed relative to a conventional security door or fire door having a panic or touch bar type unlatching assembly wherein the security gate can be mounted relative to the door to secure the emergency exit when the door is opened but allow light and ventilation through the exit opening and wherein the door, when closed, is simultaneously opened when the security gate is opened during an emergency without any modifications or alterations being made to the door or it&#39;s locking and latch release mechanisms such that the integrity of the door and it&#39;s lock assembly is not effected or compromised.  
      It is another object of the invention to provide a security gate for a security or fire door wherein increased security is provided at a security exit when both the gate and the door are closed and locked but wherein the gate and door may be simultaneously opened in an emergency and wherein installation of the gate is cost effective as no alteration or changes in the installation of the conventional door are required. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      A better understanding of the invention will be had with reference to the accompanying drawings wherein:  
       FIG. 1  is front elevation view of the security gate of the invention in a closed position with respect to a closed security or fire door;  
       FIG. 2  is a rear elevation view of the security gate shown in  FIG. 1  with the security door in an open position;  
       FIG. 3  is a cross sectional view taken along line  3 - 3  of  FIG. 1 .  
       FIG. 4  is a view similar to  FIG. 3  showing illustrating the manner in which the security gate engages the panic bar operating mechanism of the security door to simultaneously unlatch and open the gate and the door; and  
       FIG. 5  is an enlarged perspective view of the operating mechanism for unlatching the door lock as the security gate is being opened. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
      With continued reference to the drawing figures, a security gate  10  for use with a conventional security, emergency or fire door  12  is shown that permits the door to be selectively opened when the gate is locked such that a protected area interior of the door and gate remains secured. The door  12  is preferably constructed of at least a metal shell that contains a fireproof material. The door is shown as being mounted within an emergency exit “E” by way of conventional heavy duty hinges  14  that are secured to a door frame “F” in a conventional manner so that the door pivots between a closed position, as shown if  FIGS. 1 and 3 , to an open position, as shown in  FIGS. 2 and 4 , toward the outside “O” of a wall “W”. When in a closed position, the door  12  prevents unauthorized access to a protected area “A” along an inside “I” of the wall “W”.  
      The emergency door  12  includes a conventional lock assembly  15  that has at least one latch  16  that is normally seated within a latch plate housing  17  mounted within the door frame “F”. The latch  16  is withdrawn from engagement within the latch plate housing by pushing in on a touch or “panic” bar  18  associated with the lock assembly. The touch bar provides an elongated operating mechanism that is of conventional construction such that, when engaged, provides the necessary leverage and/or force to move the latch  16  to a withdrawn position to permit the emergency door to pivot to it&#39;s open position.  
      The emergency exit doors are used in commercial and industrial buildings as well as some residential buildings such as dormitories, condominiums, hotels and the like. The doors are designed to open to the outside so as to not interfere with free exit from the building during an emergency. The doors are normally closed and are not opened unless the exit is supervised in order to prevent unauthorized entry.  
      To permit the emergency door  12  to be selectively opened to allow light to enter into the enclosed area “A” and/or to permit ventilation through the exit opening “E”, while still prohibiting unauthorized access through exit, the security gate  10  is designed to be easily installed to the inner portion of the door frame “F” or to the inner portion “I” of the wall “W” adjacent the exit opening so as to be in direct facing relationship with the door  12 . The gate is normally retained in a closed and locked position as is shown in  FIG. 3 .  
      In the embodiment shown, the gate  10  includes an outer mounting frame  20  formed of tubular steel that is anchored surrounding the exit opening by appropriated bolts or other fasteners  19 , as shown in  FIG. 1 . The gate  10  is connected by hinges  21  to the mounting frame so as to be pivoted from a closed position shown in  FIG. 3 , to an open position as shown in  FIG. 4 .  
      The gate includes a peripheral frame member  22  also formed of tubular steel that is reinforced by horizontal cross frame members  24 , two being shown in the embodiment, as well as vertical reinforcing members  25 . A heavy duty or heavy gauge steel mesh  26  is welded or otherwise secured to the frame components in order to provide a barrier through which light and air can pass but wherein the spacing of the frame components and the mesh material prohibits small animals such as mice, rats and the like from passing there through. In this manner, the gate is designed to withstand tampering by an individual attempting to penetrate the gate in an unauthorized manner.  
      The gate carries a lock and latch assembly  28  that may be of any heavy duty and conventional type and may include a panic bar type operating assembly as discussed with respect to the door  12 . However, in the embodiment shown, a latch  29  is withdrawn from a latch plate housing  30  welded or otherwise secured to the outer mounting frame  20  by operation of push handle mechanism  32 .  
      In an emergency situation when the emergency door  12  is open and the gate  10  is locked and closed, the handle mechanism  32  is engaged to cause the latch to withdraw to permit the gate to pivot to its open position. The lock and latch assembly  28  may include a key device that permits authorized opening of the latch from the outside of the emergency exit.  
      When both the emergency door and the security gate are closed, the gate provides an increased measure of security to prevent unauthorized access to the protected area. However, in the event of an emergency, both the door and gate must be quickly and easily opened from the inside in order to permit a rapid and unobstructed exit from the protected area or space.  
      In this respect, the gate carries an engagement mechanism  40  for engaging the touch bar or “panic” bar  18  to thereby effectively unlatch the latch  16  from the latch plate housing  17  of the door  12  as the gate is being opened by the handle  32  being engaged to release the latch  29  from the latch housing  30 . To prevent any binding between the gate and the touch bar of the door and to reduce frictional forces there between as the gate engages the door, the engagement mechanism is preferably formed including a roller  45 . The roller is vertically mounted to a unshaped bracket  46  that is welded of otherwise secured to the outer surface  48  of the gate, as is shown in  FIG. 5 . The roller is mounted to the bracket  46  using a bolt of pin  48  that is retained by a nut (not shown) or that is welded in place to prevent tampering. Appropriate bearings may be provided to facilitate the free rotation of the roller.  
      In an emergency with both the door and gate closed, when a person pushes in on the handle  32  to open the gate  10 , roller  45  immediately engages the touch bar  18  and rolls along the bar as the bar is pushed in to release the door  12  so that both the gate and the door are opened simultaneously.  
      One of the important features of the invention is that the gate may be installed without any need to move, adjust, rebuild or modify the emergency door. This allows the gate to be economically mounted for use with substantially all existing emergency doors or mounted or installed as a unit with newly installed emergency doors. Additionally, due to the rolling contact between the gate and the emergency door using the preferred embodiment of the invention described, the gate and door may be easily opened in an emergency without fear of jamming or interference of components of the gate and the door.  
      The foregoing description of the preferred embodiment of the invention has been presented to illustrate the principles of the invention and not to limit the invention to the particular embodiment described and illustrated. It is intended that the scope of the invention be defined by all of the embodiments encompassed within the following claims and their equivalents.