Abstract:
A gun port having a door with spaced-apart plates provides armor against ballistic weapons and explosive blasts. Such a gun port is useful in defense of armored vehicles, armored buildings, and other installations. Sliding or rolling such a gun port door across a gun port opening horizontally on guide rails allows for ease of use by both persons who are left handed or right handed. A door slide sub-assembly is easily mounted or un-mounted from a separate port frame installed in a vehicle or building wall, providing easy repair of the door and door slide sub-assembly, and easier replacement of the port frame.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT 
     Not Applicable 
     INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention(s) relates to gun ports, and in particular to gun ports with blast-resistant doors and/or to gun ports with doors that slide or roll horizontally into and out of a closed position over a gun port opening, useful in defense of armored vehicles, armored buildings, and other installations. 
     2. Description of the Related Art 
     Gun ports are well known in the art for both military and non-military application. A gun port permits discharge of a fire arm through an opening defined within the gun port whenever the gun port is in an open position. The gun port secures the port against passage of a bullet or other unwanted object or fluid whenever the gun port is in a closed position. Typically gun ports include a door as a closure shield secured on either an interior or exterior surface of a support apparatus such as an exterior wall of an armored vehicle or the exterior wall of a building. The door is often actuated by an operator of the gun port standing or sitting next to an interior surface of the support apparatus, such as inside the armored vehicle or building. Examples of the prior art in gun ports are provided by U.S. Pat. Nos. 4,771,672; 4,771,673; and 6,425,311. In all three of these examples, the door consists of a single plate of metal. The first example discloses a door (or “closure plate”) that is a single plate that is slid upward to open, and downward to close. The second example discloses a door (or “closure”) that is a single plate that is pivoted inward and downward to open, and upward and outward to close. The third example discloses a door (or “closure shield”) that is a single plate mounted on the outside of the exterior wall and that rotates parallel to the wall in a first rotational direction to open, and in the reverse direction to close. 
     The prior art does not disclose gun ports designed to withstand explosive blasts from military or terrorist threats. What are needed are gun ports that can withstand explosive blasts, and at the same time are constructed of preassembled subassemblies that enable easy installation and replacement. 
     BRIEF SUMMARY OF THE INVENTION 
     The invention(s) is pointed out with particularity in the appended claims. However, some aspects of the invention(s) are summarized in the following descriptions of some possible implementation examples and aspects. 
     One implementation of the invention(s) includes a gun port comprising a port frame coupled to a movable, blast-resistant door. The door can be rolled or slid in either of two opposite directions and comprises at least two spaced-apart plates, wherein the at least two spaced-apart plates can be made of steel. The door can be moved out of the way of a port opening in either of two directions along guide rails, and a handle is included that can be grasped by either a user&#39;s left or right hand and used to move the door either to the left or to the right. The door position can be latched into any of multiple, fixed locations and can be restrained by at least an upper or lower protection bar. The door can also be restrained by left and right end plates. The gun port can optionally further comprise one or more drip bars, at least one ricochet bar, and at least one rain slot. 
     Objects and Advantages of the Invention 
     Objects and advantages of the present invention(s) are numerous. One object and advantage is a port door that has been tested to withstand ballistic projectiles and explosive blasts from outside the port. The blast testing has shown that a gun port of the present invention(s) can reduce outside blast pressures of 25 psi outside down to pressures inside of less than 0.5 psi. This is accomplished by constructing a gun port door that is close fitting against a port frame. It is also accomplished with a door that is constructed with not just with one steel plate to close the opening of the port, but with a stack of two or more spaced-apart steel plates, wherein the steel can be A36 carbon steel rather than more exotic and expensive steels, and wherein the space between adjacent plates can simply be air space and spacer standoffs. In one such design, an outer plate of 1.5 inch (3.81 cm) thickness is spaced 1.625 inch (4.13 cm) from an inside plate of 1 inch (2.54 cm) thickness. A second object and advantage is a door handle that can be manually moved left or right to open a closed port with either hand of a shooter or other user. A third object and advantage is a door that moves on rollers or slides, wherein the rollers or slides are protected by being located between the spaced apart plates of the door. Within this disclosure, “slide” can imply either sliding or rolling. A fourth object and advantage is a door sub-assembly, including movement guides, that can be removed and replaced easily from the inside or safe-side of its port frame. A fifth object and advantage is a door that can be latched into a fixed position at any one of a number of alternative stop positions, allowing the door to be opened by different amounts from the fully closed position. Additional advantages include optional inclusion of one or more ricochet stops, which may include a drip slot, and drip bars (also called drip ringlets). 
     The various features and further advantages of the present invention(s) and their preferred embodiments will become apparent to ones skilled in the art upon examination of the accompanying drawings and the following detailed description. It is intended that any additional advantages be incorporated herein. The contents of the following description and of the drawings are set forth as examples only and should not be understood to represent limitations upon the scope of the present invention(s). 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The foregoing objects and advantages of the present invention(s) of gun ports may be more readily understood by one skilled in the art with reference being had to the following detailed description of several embodiments thereof, taken in conjunction with the accompanying drawings. Within these drawings, callouts using like reference numerals refer to like elements in the several figures (also called views) where doing so won&#39;t add confusion. Within these drawings: 
         FIG. 1  shows a perspective view from the inside and from the left side of a gun-port door on a door slide sub-assembly. 
         FIG. 2  shows a similar perspective view of the door and slide of  FIG. 1  separated from their sub-assembly. 
         FIG. 3  shows a similar perspective view of the guide rails as used in the slide of the door slide sub-assembly of  FIG. 1 . 
         FIG. 4  shows an end view as viewed from the left of the parts shown in  FIG. 3 . 
         FIG. 5  shows a similar end view to that of  FIG. 4 , but of the door slide sub-assembly with the door and left end plate removed. 
         FIG. 6  shows a similar end view to that of  FIG. 5 , but with door included. 
         FIG. 7  shows a perspective view from the inside and from the left side of a gun port frame and opening. 
         FIG. 8  shows a cross-sectional view from the left side of the gun port frame shown in  FIG. 7 . 
         FIG. 9  shows a view looking toward the outside from the inside or safe side of the gun port frame shown in  FIG. 7 , and showing the opening through the gun port frame. 
         FIG. 10  shows the perspective view of  FIGS. 1 and 7  but showing the door slide sub-assembly mounted on the port frame, and showing a gun barrel directed through the gun port opening. 
         FIG. 11  shows a view from the left side of a gun port installed into a wall of a vehicle or building, where the wall is shown in cross-section. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The following is a detailed description of the invention(s) and its preferred embodiments as illustrated in the drawings. While the invention(s) will be described in connection with these drawings, there is no intent to limit it to the embodiment or embodiments disclosed. On the contrary, the intent is to cover all alternatives, modifications and equivalents included within the spirit and scope of the invention(s) as defined by the appended claims. 
       FIG. 1  shows a perspective view from the inside and from the left side of a gun-port door  24  that is part of a door slide sub-assembly  10 . The door  24  rolls or slides along upper guide rail  12  and lower guide rail  14  that are co-parallel to one another and supported by upper beam  16  and lower beam  18  respectively. The upper and lower beams  16 , 18  are fastened to left end plate  20  on the left, and to right end plate  22  on the right. The door  24  itself is shown comprising an outer door plate  26  spaced apart from an inner door plate  28  and a door handle  30 . There are an upper support plate  40  and a lower support plate  42  fastened to the upper beam  16  and lower beam  18  respectively; these support plates will be seen in  FIGS. 5 ,  6 ,  10 , and  11  to be the means by which this door slide sub-assembly  10  can be mounted to a port frame  80  by multiple fastener holes such as a fastener hole  44 . An upper spacer bar  46  is fastened to the upper beam  16 , and an upper protection bar  48  is fastened to the upper spacer bar  46 . A lower spacer bar  50  is fastened to the lower beam  18 , and a lower protection bar  52  is fastened to the lower spacer bar  50 . These protection bars  48 , 52  help to keep the door  24  from being blown off of the guide rails  12 , 14  when the door is subjected to forces of an explosive blast from outside the door  24  pushing toward the inside of the door  24 . The upper and lower beams  16 , 18  and the upper and lower guide rails  12 , 14  also help in this regard. “Inside” is on the side of the door  24  that faces the foreground of this perspective view, while “outside” is on the opposite side of the door  24  that faces the background of this view. There is a left spring latch  54  installed within the left side of the lower protection bar  54 , and a right spring latch  56  installed within the right side of the same lower protection bar  54 . Spring latches  54 , 56  can be used to engage latch engagement holes such as the latch engagement hole  58 ; multiple latch engagement holes are shown lined up along a direction parallel to the bottom edge of the inner door plate  28 . The outer and inner door plates  26 , 28  are held spaced apart by pipe spacers  64  shown in  FIG. 6 , and the door  24  uses door rollers  66  to move along the guide rails  12 , 14  (these rollers  66  are also shown in  FIG. 6 ). In this view, the holes for four spacer fasteners  60  and four roller fasteners  62  can be seen on the inside of the inner door plate  28 . Each of the set of four spacer fasteners  60  and the set of four roller fasteners  62  are arranged in a rectangular grid pattern. The door  24  is a blast-resistant door. Within this disclosure, “blast-resistant door” is defined to mean a door comprising two or more generally co-parallel layers of armor spaced apart from one-another. 
       FIG. 2  shows a similar perspective view of the door  24 , the left end plate  20 , and the slides  12 , 14  separated from one another from their door slide sub-assembly  10  shown in  FIG. 1 . 
       FIG. 3  shows a similar perspective view of the guide rails  12 , 14  as used in the door slide sub-assembly  10  of  FIG. 1 . This view also shows the beams  16 , 18  which support the guide rails  12 , 14 . The right end plate  22  is shown supporting the right ends of the guide rails  12 , 14  and the beams  16 , 18 . 
       FIG. 4  shows an end view as viewed from the left of the parts shown in  FIG. 3 . These parts are the right end plate  22 , the beams  16 , 18 , and the guide rails  12 , 14 . 
       FIG. 5  shows a similar end view to that of  FIG. 4 , but of the door slide sub-assembly, but with the door  24  and left end plate  20  removed. 
       FIG. 6  shows a similar end view to that of  FIG. 5 , but with door  24  included (showing callout numbers for some of the parts of the door, but without the callout number  24  for the door as a whole). The parts of door called out are the outer and inner door plates  26 , 28 , the door handle  30 , pipe spacers  64 , and rollers  66 . 
       FIG. 7  shows a perspective view from the inside and from the left side of a gun port frame  80  and opening  114 . In one implementation, the size of the opening  114  (or window) measures approximately 12 inches by 12 inches (30 cm by 30 cm). The gun port frame  80  comprises a left side wall  82  and a right side wall  84  as well as a ceiling  86 , a sloped inner floor  88 , and a horizontal outer floor  90 . The sloped inner floor  88  allows for a smaller area of opening on the inside than on the outside of the opening  114 . On the sloped inner floor  88 , near the inside of the opening  114 , is a ricochet bar  100  to stop projectiles from passing through the opening  114  should they first strike the sloped inner floor  88 . A rain slot  102  divides left and right portions of the ricochet bar  100  and allows water to drain from accumulating behind the ricochet bar  100 . In this view a lower edge of a drip bar  98  can be seen within the upper part of the opening  114 ; drip bars such as the one visible are used to trap rain drops that might otherwise enter the opening  114  from outside the gun port frame  80 . Attached to the ceiling  86  is an upper mounting plate  94 , and attached to the sloped inner floor  88  and to the horizontal outer floor  90  is a lower mounting plate  92 . Both mounting plates  92 , 94  include mounting holes such as mounting hole  96 . These mounting plates  92 , 94  are where the upper and lower support plates  40 , 42  of the door slide sub-assembly  10  attach (as in  FIG. 1 ). Facing outward from the port frame  80  is a left exterior flange  104  attached to the left side wall  82 ; a right exterior flange  106  attached to the right side wall  84 ; a top exterior flange  108  attached to the ceiling  86  and to both left and right side walls  82 , 84 ; and a bottom exterior flange  110  attached to the horizontal outer floor  90  and to both left and right side walls  82 , 84 . 
       FIG. 8  shows a cross-sectional view from the left side of the gun port frame  80  shown in  FIG. 7 . In this view, a filler strip  112  is seen welded between the lower end of the sloped inner floor  88  and the bottom exterior flange  110  providing a more smoothly contoured surface between these two other parts  88 , 112 . 
       FIG. 9  shows a view looking toward the outside from the inside or safe side of the gun port frame  80  shown in  FIG. 7 , and showing the opening  114  through the gun port frame  80 . 
       FIG. 10  shows the perspective view of  FIGS. 1 and 7  but showing the door slide sub-assembly  10  mounted on the port frame  80 , and showing a gun barrel  154  directed through the gun port opening  114 . Mounting bolts  144  are shown holding the door slide sub-assembly  10  to the inside of the port frame  80 . 
       FIG. 11  shows a view from the left side of a gun port  152  installed into a wall  146  of a vehicle or building, where the wall  146  is shown in cross-section and having an outside wall surface  148  and an inside wall surface  150 . The exterior flanges of the gun port frame  80  are shown fitted against the outside wall surface  148 . 
     Other embodiments may include within the space between plates of the door  24  shock absorbing ceramic, plastic, or metal foam material, or even laminations of sheets of various materials. Additional features may be added, such as a gun rest. And the top, bottom, or sides in general of a port frame  80  may be angled to create a port opening  114  that is larger inside than outside, as to create an embrasure. 
     Embodiments of the present invention(s) include methods of using gun ports of the present invention(s). One such method comprises steps of: a) manually sliding a port door along guide rails to at least a partially open position from a closed position and thus exposing a opening in a gun port frame, b) inserting the barrel of a gun through the opening, and c) shooting the gun. Another such method comprises steps of a) removing the barrel of a gun from an opening in a gun port and b) manually sliding a port door along guide rails to a closed position. 
     Although specific embodiments of the invention(s) have been illustrated and described herein, those of ordinary skill in the art will appreciate that any arrangement configured to achieve the same purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments of the invention(s). It is to be understood that the above description has been made in an illustrative fashion, and not a restrictive one. Combinations of the above embodiments, and other embodiments not specifically described herein will be apparent to those of skill in the art upon reviewing the above description. The scope of various embodiments of the invention(s) includes any other applications in which the above structures and methods are used.