Security device

A security device for preventing unauthorized separation of a door from a cooperating buck assembly, in which first and second plate members are respectively carried by the door and the buck assembly and cooperate with each other to prevent movement of the door in a lateral direction when the door is closed. The first plate member is of unique configuration and is arranged to interlock with adjoining structure on the second plate member to keep the door from moving in its plane. In certain embodiments a Z-shaped support element separate from the plate members is mounted on the buck assembly in juxtaposition with the second plate member, and in some cases either the first plate member or the second plate member includes a pivotally supported cam element which moves into cooperating relationship with the other member as the door reaches its fully closed position.

BACKGROUND OF THE INVENTION 
This invention relates to security apparatus and more particularly to 
apparatus for preventing unauthorized separation of a door from a 
cooperating buck assembly. 
As is well known, many types of access doors in present usage are hinged or 
pivoted along one vertical edge to a cooperating rectangular frame 
commonly referred to as a door buck. The opposite vertical edge carries a 
spring biased latch within the door which protrudes into a mating opening 
in a strike plate on the buck assembly when the door is closed. The latch 
may be locked to secure the door in its closed position. 
One of the ways of gaining unauthorized entry through a door which has been 
locked in this manner is to wedge a crowbar or similar burglar's tool 
between the door and the buck assembly and then pry the two apart. The 
door moves in its plane and becomes bowed sufficiently to carry the latch 
away from the strike plate by a distance equal to the latch's penetration 
in the strike plate opening. The door may then be readily moved to its 
open position. 
Although attempts have been made heretofore to prevent such authorized 
entry through the use of interlocking plates and similar devices, these 
attempts have proved deficient in many respects. As an illustration, and 
this was of special moment in the mounting of the plates on a pre-existing 
door and buck installation, difficulties were encountered in positioning 
the plates in their proper locations. In addition, in several previous 
arrangements of this type the apparatus was deficient in providing the 
desired locking action with the necessary structural rigidity to do a 
really effective job. Further difficulties were encountered in arranging 
the interlocking plates such that they remained in position even after 
successive attempts to force the door. 
SUMMARY 
One general object of this invention, therefore, is to provide new and 
improved apparatus for preventing unauthorized separation of a door from a 
cooperating buck assembly. 
More specifically, it is an object of this invention to provide such 
apparatus which may be readily positioned on a pre-existing door and buck 
assembly installation. 
Another object of the invention is to provide apparatus of the character 
indicated which exhibits good structural rigidity and remains in position 
even after repeated attempts to pry the door and buck assembly apart. 
A still further object of this invention is to provide a novel security 
installation of comparatively simple construction which is economical to 
manufacture and thoroughly reliable in operation. 
In one illustrative embodiment of the invention, the apparatus includes a 
first plate member parallel to and carried by the door and a second plate 
member carried by the buck assembly in a plane transverse to the door. A 
latch or other locking mechanism is mounted within the door at the level 
of the second plate member. The second plate member has a strike portion 
in position to cooperate with the locking mechanism and an anti-tampering 
portion which projects beyond the edge of the buck assembly toward the 
first plate member in coplanar relationship with the strike portion. A 
vertically extending slot or appropriate structural elements on the first 
plate member receive the second plate member when the door is closed to 
prevent movement of the door in its plane. Upon the locking of the door, 
the locking mechanism remains in cooperating relationship with the strike 
portion of the second plate member, and cannot be separated therefrom, by 
bending the door because of the interaction between the plate members. 
In accordance with one feature of the invention, in certain particularly 
important embodiments, a Z-shaped support element separate from the plate 
members is mounted on the buck assembly in juxtaposition with the second 
plate member. The support element provides substantial structural rigidity 
for the anti-tampering portion of the second plate member and is 
permanently affixed to the buck assembly in a manner such that the element 
remains in place even after repeated efforts to force the door. 
In accordance with another feature of the invention, in several 
advantageous arrangements, the first plate member extends substantially 
the entire length of the door in a plane parallel thereto. The first plate 
member includes a vertically extending slot which is arranged such that 
the second plate member may be located on the buck assembly in 
substantially any convenient position without the necessity for precise 
vertical alignment relative to the slot. 
In accordance with a further feature the invention, in some embodiments, 
either the first plate member or the second plate member is provided with 
a pivotally mounted cam portion which swings into cooperating relationship 
with the other plate member as the door reaches its fully closed position. 
These embodiments enable the realization of extremely effective locking 
action upon the closing and latching of the door. 
The present invention, as well as further objects and features thereof, 
will be understood more clearly and fully from the following description 
of certain preferred embodiments, when read with reference to the 
accompanying drawings.

DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS 
Referring to FIGS. 1 and 2 of the drawings, there is shown a door 30 of 
generally conventional construction. The door 30 is hinged or pivoted 
along one vertical edge (not visible in the drawings), and its opposite 
vertical edge is arranged for movement in the direction shown 
schematically by the arrows 31 toward a cooperating frame or buck assembly 
32, only a portion of which is illustrated in the drawings. The 
illustrated portion of the assembly 32 comprises an upstanding post of 
rectangular cross-section which may be of sheet metal construction. The 
post is disposed around the free edge of an interior building partition or 
wall 34 and includes the usual stop member 36 for the door. 
A lock mechanism having a spring-biased latching tongue 37 is recessed 
within the free edge of the door 30. As will be understood, the tongue 37 
may be locked in its extended position when the door is closed through the 
use of a key or other locking tool. 
A vertical door plate 38 is rigidly secured to the free edge of the door 
30, as by screws 40. The plate 38 extends substantially the entire length 
of the door 30 in a plane parallel thereto and is mounted on the door's 
interior surface, that is, the surfaces within the room or other 
inclosure. The outboard portion 41 of the plate 38 protrudes a short 
distance beyond the free edge of the door and is provided with a vertical 
slot 32. This slot extends substantially the entire length of the plate 38 
such that its upper end is located a short distance beneath the ceiling 
and its lower end is disposed a short distance above the floor. 
Recessed in the exposed edge of the buck assembly 32 at the level of the 
latching tongue 37 is a strike plate 45. The recessed portion 47 of the 
plate 45 is secured to the buck assembly 32 in the usual way and is 
provided with an opening 49 in alignment with a mating opening 50 (FIG. 2) 
in the buck assembly. The openings 49 and 50 are located in position to 
receive the tongue 37 when the door 30 is in its closed position. The 
plate 45 additionally includes an anti-tampering portion 52 which projects 
beyond the edge of the buck assembly 32 toward the door plate 38. The 
portions 47 and 52 of the plate 45 define a single flat plane which 
extends in a plane transverse to that of the door and the attached plate 
38. 
Also mounted on the buck assembly 32 is a Z-shaped support plate 54. The 
plate 54 is entirely separate from the strike plate 45 but is located in 
close juxtaposition therewith such that the plate 54 serves as a support 
for the strike plate. The plate 54 comprises an edge flange 56 in parallel 
abutting relationship with the anti-tampering portion 52 of the strike 
plate, an intermediate flange 57 extending in a direction parallel to the 
door plate 38, and a transverse flange 59 which is spaced from and 
parallel to the edge flange 56. The intermediate flange 57 is rigidly 
affixed to the buck assembly by screws 60, and the transverse flange 59 
extends around the adjacent corner of the buck assembly such that the 
plate 54 provides extremely firm support for the anti-tampering portion 
52. 
To assemble the apparatus on an existing door and buck assembly, the door 
plate 38 is attached to the free edge of the door 30 by the screws 40, and 
the vertical slot 42 is aligned with the strike plate 45. This latter 
plate may be disposed at any convenient height along the buck assembly 32. 
In cases in which the buck assembly is provided with a conventional strike 
plate, it is removed and the plate 45 substituted therefor. The Z-shaped 
support plate 54 is oriented with its edge flange 56 in abutting 
relationship with the protruding portion 52 of the plate 45 and is secured 
in place by the screws 60. In some cases one or more additional strike 
plate and support plate assemblies are added at spaced locations along the 
length of the buck assembly. The additional plates are similar in 
construction to the plates 45 and 54, but they need not include the 
opening 49 for the latching tongue 37. 
As the door 30 moves in the direction of the arrows 31 to its closed 
position, the anti-tampering portion 52 of the strike plate 45, together 
with the edge flange 56 of the support plate 54, move into the vertical 
slot 42 in the door plate 38. With the latching tongue 37 locked in its 
position within the openings 49 and 50, the door may not be opened as long 
as the tongue 37 remains within these openings. Any attempt to move the 
door in its plane through a distance sufficient to withdraw the tongue 37 
from the openings is prevented by the location of the anti-tampering 
portion 52 within the slot 42. The portion 42 is positively and firmly 
supported by the Z-shaped plate 54 with the result that the portion 52 
remains within the slot 42 even after repeated efforts to force the door. 
FIG. 3 is illustrative of an alternative door plate 65 that may be 
substituted for the plate 38 of FIGS. 1 and 2. The plate 65 defines a 
plurality of vertically extending slots 66 which are located in spaced 
relationship with each other and in vertical alignment with the 
anti-tampering portion 52 of the strike plate 45. These slots cooperate 
with the portion 52 and the adjacent flange 56 on the support plate 54 in 
the manner described above to prevent movement of the door 30 in its plane 
when the door is in its closed position. The use of an interrupted slot 
arrangement of the type illustrated in FIG. 3 provides additional 
structural rigidity but affords slightly less flexibility in the 
installation of the apparatus on an existing door and buck assembly. 
In the embodiments of the invention illustrated in FIGS. 1-3, the door 
plate extends substantially the entire length of the door from the floor 
to the ceiling of the enclosure. An advantage of this arrangement is that 
one or more of the Z-shaped plates 54 may be positioned at a wide variety 
of locations along the vertical length of the buck assembly 32 depending 
on the accessibility of the installation and the desired structural 
rigidity. In cases in which the plate 54 is used without the 
anti-tampering portion 52 of the strike plate 45, the flange 56 on the 
plate 54 protrudes through the slot on the door plate to prevent the door 
from moving in its plane. 
In other good embodiments, the apparatus includes a substantially shorter 
door plate which is approximately coextensive with the cooperating strike 
plate. Referring to the embodiment of FIGS. 4-7, for example, there is 
provided a door plate 70 extending along only a small part of the vertical 
length of the door 30 in a plane parallel thereto. The plate 70 is offset 
slightly from the plane of the door and includes a vertically extending 
T-shaped slot 71 having an enlarged opening 72 adjacent the side of the 
plate away from that affixed to the door. 
When the door 30 is in its closed position, the door plate 70 cooperates 
with a Z-shaped plate 80 to prevent movement of the door in its plane. The 
plate 80 includes an anti-tampering flange 81, an intermediate flange 82 
affixed to the buck assembly 32 and an end flange 83 parallel to the 
flange 81. A vertically extending slot 73 in the anti-tampering flange 81 
accommodates the operating portion 74 of a pivotally mounted element 75. 
The portion 74 has a curved exterior face which forms a camming surface 
87. The flange 81 is of C-shaped configuration with the arms of the "C" 
forming the upper and lower ends of the slot 73. A pair of vertically 
aligned tubular members 76 and 77 are respectively located on the arms, 
and these members receive a pivot rod 78 which is welded or otherwise 
suitably affixed to the element 75. The element 75 is normally located in 
coplanar relationship with the flange 81 but is movable about the axis of 
the rod 78 in a manner that will become more fully apparent hereinafter. 
Upon the movement of the door 30 toward its closed position, the 
anti-tampering element 75 enters the enlarged opening 72 in the door plate 
70 in the manner illustrated in FIG. 5. As the door continues its movement 
and approaches the FIG. 6 position, the edge of the opening 72 engages the 
camming surface 87 to pivot the element 75 in a counterclockwise 
direction, as viewed in this Figure, about the axis of the rod 78. When 
the door reaches its fully closed position (FIG. 7), the element 75 is 
disposed in the plane of the plate 70 at right angles to its initial 
position, and the portion 74 of the element 75 is located in the shorter 
part of the slot 71. 
Should an attempt be made to force the door 30 by moving it in its plane, 
the possibility of such movement is precluded because of the location of 
the anti-tampering flange 81 of the z-shaped plate 80 within the vertical 
slot 71 on the door plate 70. When the door is unlocked and moved to its 
open position, the plate 70 is carried away from the plate 80 to withdraw 
the anti-tampering flange 81 from the slot 71. The element 75 on the 
flange 81 returns through a clockwise angle of ninety degrees, as viewed 
in FIG. 7, to the position illustrated in FIG. 5. In this position the 
element is again aligned in coplanar relationship with the flange 81. 
FIGS. 8-14 are illustrative of another preferred embodiment of the 
invention. This latter embodiment includes a door plate 90 which is 
provided with a vertically extending slot 92 communicating with a 
comparatively large rectangular opening 94. The opening 94 accommodates a 
pivotally mounted anti-tempering element 96 which is supported by two 
hinge elements 98 and 99 and a vertically extending pivot rod 101. The 
elements 98 and 99 are welded or otherwise suitably affixed to the door 
plate 90 above and below the element 96. The element 96 is urged by 
biasing springs 102 (FIG. 10) into coplanar relationship with the plate 70 
and is provided with a vertical slot 103. The slot 103 extends in a 
direction parallel to that of the pivot rod 101 on the side of the rod 
remote from that adjacent the door. 
The door plate 90 is located in position to cooperate with a z-shaped plate 
105 which is affixed to the buck assembly in a manner similar to that 
described heretofore. The plate 105 includes an anti-tampering flange 106 
which extends in a plane transverse to that of the door, an intermediate 
flange 110 extending in a direction parallel to the door, and a transverse 
flange 112 which is spaced from and parallel to the flange 106. The flange 
106 is provided with a protruding vertical ridge 113 on its outwardly 
disposed face of the flange. 
As the door is moved toward its closed position, the anti-tampering flange 
106 enters the vertical slot 92 in the door plate 90 and engages pivotally 
mounted element 96. The flange 106 contacts the element 96 a short 
distance on the inner or left-hand side, as viewed in FIG. 11, of the 
pivot rod 101, and the element 96 swings in a counterclockwise direction, 
as seen in this Figure, about the axis of the rod through an angle of 
approximately ninety degrees. The element 96 moves through the position 
illustrated in FIG. 12 and comes to rest in the FIG. 13 position with its 
inner surface in coplanar abutting relationship with the exterior surface 
of the flange 106. In this position the protruding vertical ridge 113 on 
the flange 106 is disposed within the vertical slot 103 in the element 96. 
The door is then locked in the conventional manner to carry the latching 
tongue 37 into its corresponding opening. 
Should an attempt be made to force open the door, the location of the 
anti-tampering flange 106 within the vertical slot 92 prevents movement of 
the door in its plane. In addition, slippage between the flange 106 and 
the element 96 is prevented by the vertical ridge 113 within the slot 103. 
To again open the door to obtain authorized entry into the enclosure, the 
latching tongue 37 is unlocked, and the door is then swung to its open 
position. As illustrated in FIG. 14, during the initial movement of the 
door the element 96 pivots in a clockwise direction under the action of 
the springs 102 (FIG. 10) to carry the slot 103 away from the vertical 
ridge 113 and to return the element to its initial position in coplanar 
relationship with the door plate 90. 
Referring now to FIGS. 15-18, there is shown still another illustrative 
embodiment of the invention. The door 30 of these latter figures includes 
a door plate 120 which extends in a plane parallel to the door and is 
provided with an offset portion 121 such that the plate is spaced a short 
distance from the door's inner surface. A pair of ears 122 and 123 are 
respectively disposed in a single vertical plane on the upper and lower 
edges of the door plate. 
Mounted on the buck assembly 32 is an L-shaped support plate 125. The plate 
125 includes a first flange 126 extending in a plane parallel to that of 
the door plate 120 and a second flange 127 which meets the flange 126 at a 
right angle. The flange 126 is suitable affixed to the buck assembly 32 
and is provided with upper and lower tabs 130 and 131, respectively. These 
tabs protrude horizontally toward the door plate 120 in positions which 
just clear the upper and lower edges of the door plate. 
As the door 30 swings toward its closed position, the offset portion 121 of 
the plate 120 moves between the tabs 130 and 131 on the anti-tampering 
plate 125. In the fully closed position of the door (the position shown in 
FIG. 18) the ears 122 and 123 are located in close juxtaposition with the 
respective tabs 130 and 131 on the sides of the tabs opposite those facing 
toward the door hinge. When the door is locked, any attempt to gain 
unauthorized entry by forcing the door in its plane brings the ears 122 
and 123 into engagement with the adjacent portions of the tabs 130 and 131 
and prevents the door from moving a distance sufficient to withdraw the 
latching tongue 37 from its corresponding opening. The arrangement 
provides extremely effective locking action upon the closing and latching 
of the door. 
The terms and expressions which have been employed are used as terms of 
description and not of limitation, and there is no intention in the use of 
such terms and expressions of excluding any equivalents of the features 
shown and described or portions thereof, but it is recognized that various 
modifications are possible within the scope of the invention claimed.