Door forcing apparatus

The door forcing apparatus for forcing a door set in a door jamb comprises two side rails each having a substantially L-shaped cross section engagable with a beveled edge between the door jamb and the door, a plurality of nearly flat drive wedges pivotally mounted on the side rails adjacent their vertices each having a nearly flat foot oriented parallel to the door pivotally mounted adjacent their circular-arc-shaped edge pressible against the door, two adjustable braces each of which comprise a bracing hydraulic cylinder or a turnbuckle which is pivotally attached to each of the two side rails adjacent one end of the apparatus, two U-shaped-cross-sectioned drive rods on each of which the drive wedges connected to the side rails are pivotally mounted and two driving hydraulic cylinders, each of which has a piston rod pivotally attached to an end of one of the drive rods and whose cylinder is pivotally mounted on a support bracket at one end of a side rail.

THE FIELD OF THE INVENTION 
The present invention relates to means for forcible entry into a locked 
room, house, apartment and the like and, more particularly, to means for 
safely forcing a locked door which opens inward from the exterior, and 
with the use of accessories almost any door. 
THE BACKGROUND OF THE INVENTION 
Law enforcement or military personnel are required to make a forcible entry 
into a room in an apartment or hotel or into a house when it is necessary 
to make an arrest, rescue or for other purposes. Particularly 
anti-terrorist teams also need a rapid, safe means of forcing a door, 
often to save the lives of hostages. 
Currently when an arrest of dangerous criminals who have locked themselves 
inside a room or a house must be made, armed law enforcement personnel 
surround the room or house and guard every possible exit from the room or 
house including doors and windows. Then they force the locked door to the 
room or house manually by crowbar, by kicking the locked door in with 
their feet or similar means and may enter the room or house with ready 
weapons in an effort to overcome any resistance to arrest without loss of 
life. However this is very dangerous procedure because the criminals who 
may be drug addicts or drug dealers determined to resist arrest by any 
means are often armed and shoot through the door, which is often only made 
of wood, to thwart any attempt to force the locked door and to prevent 
arrest, if they are aware that law enforcement personnel are approaching. 
Furthermore some modern locked doors are comparatively strong, made of 
metal and very difficult to force manually or with a hand-held tool. 
Conventional means for forcing such a door are often noisy and give the 
occupants of the room or house advanced warning that the room or house is 
being entered. This is particularly a problem in hostage-terrorist 
situations where these conventional means are often too slow. 
It is an object of the present invention to provide a door forcing 
apparatus applicable to a locked door which opens inward and, with the use 
of accessories, to any locked door. 
It is another object of the present invention to provide a door forcing 
apparatus which is safely operable from a remote location so that the 
individuals operating it are not required to stand in front of the locked 
door while the door is being opened. 
It is an additional object of the present invention to provide a mechanical 
door forcing apparatus which may be used by law enforcement or military 
personnel to open a locked door without exposing themselves to gun fire 
from the interior of the locked room or house. 
It is a further object of the invention to provide a door forcing apparatus 
which can open a comparatively strong locked door which can not be forced 
manually or with a hand-held tool. 
SUMMARY OF THE INVENTION 
According to the invention the door forcing apparatus for opening a door 
mounted in a door jamb set in a wall comprises two side rails each having 
a substantially L-shaped cross section engagable with the door jamb or 
between the door jamb and the door, a plurality of wedge assemblies 
mounted on both side rails pivotable toward and engagable with the door, a 
plurality of adjustable braces each of which is pivotally attached to each 
of the side rails so that the door forcing apparatus may be collapsed when 
stored and the door forcing apparatus may be adjusted to fit various door 
widths and means for pivoting the wedge assemblies in the direction of the 
door and pressing the wedge assemblies against the door to open the door. 
The wedge assembly comprises a drive wedge pivotally mounted on one of the 
side rails and a substantially flat foot pivotally mounted on the drive 
wedge pressible flat against the door. The drive wedge essentially 
comprises a portion of a circular disk having a circular-arc-shaped edge 
and two wedge edges converging to a vertex. It is oriented substantially 
perpendicular to the door. The foot is pivotally attached to the drive 
wedge on a foot pivot adjacent the circular-arc-shaped edge and is located 
between the drive wedge and the door. The pivotable drive wedge is 
advantageously mounted on a pivot supported on one side by the side rail 
and one the other side by a support bracket attached to the side rail. A 
guide having a guide plate preventing outward pivoting of the drive wedge 
during forcing of the door can also be provided near the 
circular-arc-shaped edge of the drive wedge. 
The means for pivoting the wedge assemblies on one of the side rails in the 
direction of the door and pressing the feet of the drive wedges against 
the door to force the door comprises a driving hydraulic cylinder 
pivotally mounted at one end of each side rail and a drive rod pivotally 
attached to a piston rod of each driving hydraulic cylinder extending 
substantially in the longitudinal direction of the piston rod. The drive 
wedges of the wedge assemblies are pivotally attached to either of the two 
drive rods so that when the driving hydraulic cylinder is extended and 
moves the drive rods each of the drive wedges pivots toward the door 
pressing its foot against the door. 
The adjustable brace can comprise a turnbuckle having two 
oppositely-threaded turnbuckle screws engaged in opposite ends of an 
interiorly-threaded center pipe. The ends of the turnbuckle screws not in 
the center pipe are pivotally attached to the side rails. Alternatively 
the adjustable brace can be a bracing hydraulic cylinder which can provide 
a substantially larger bracing force. This brace hydraulic cylinder can be 
activated from a remote location. 
When the door forcing apparatus has been engaged on the door jamb of a door 
to be forced, the adjustable braces may be extended and the driving 
hydraulic cylinders are activated forcing the drive rods to move the drive 
wedges pressing the feet on the door and forcing it. Thus law enforcement 
or other personnel can force the door from a remote location not exposing 
themselves to gun fire from within the locked room or house while they are 
breaking down the door. If the door has been booby-trapped as drug dealers 
sometimes do, then, when it is opened from a remote location, law 
enforcement personnel are not injured. 
Although there are many possible different embodiments of the door forcing 
apparatus and applications of it utilizing electric motors, magnetic 
coils, pneumatic and ratchet devices, to name a few, to apply the force 
and energy required to force a door and although there are many ways to 
engineer the wedge assemblies and the drive linkages, the detailed 
description for the most part concerns the embodiment illustrated in the 
drawing. However the specifics referred to below are not intended to limit 
the scope of the invention as set forth in the appended claims and the 
intent is to cover every possibility.

DETAILED DESCRIPTION OF THE INVENTION 
The embodiment of the door forcing apparatus 10 shown in FIGS. 1 to 6 
comprises two side rails 23 each having an L-shaped cross section 
engagable between the locked door 11 and the door jamb 15, two adjustable 
braces 25 whose width is adjustable so that the door forcing apparatus 10 
can fit doors 11 of different widths, a plurality of wedge assemblies 21 
attached pivotally to the side rails 23 which press on the facing surface 
of the door 11, two hydraulic cylinders 31 each of which is pivotally 
connected to a base bracket 27 of a side rail 23 and two drive rods 29 
each of which is pivotally connected at one end to one of the hydraulic 
cylinders 31 and also pivotally connected to a group of the wedge 
assemblies 21 arranged in succession along the length of the drive rod 29. 
In the embodiment shown in FIG. 1 five wedge assemblies 21 are mounted 
pivotally on each drive rod 29. The wedge assemblies 21 are spaced nearly 
equally from each other along the length of the drive rod 29 on the side 
of the door 11 which does not have the door handle 13. As shown in FIG. 1a 
there is a gap between the wedge assemblies 21 which is larger than normal 
because the center wedge assembly 21 is removed to allow for the presence 
of the door handle 13. 
Each of the wedge assemblies 21 comprises a drive wedge 33 which is 
pivotally mounted on a supporting bracket 47 rigidly attached to a side 
rail 23 at wedge pivot pin 45 as shown in FIG. 6 and a pivotally attached 
foot 35. Each of the drive wedges 33 is pivotally attached to an 
advantageously rectangular, substantially flat foot 35 which is oriented 
substantially perpendicularly to the plane of the drive wedge 33 and which 
presses against the facing surface of the door 11. As shown by comparison 
of FIGS. 4 and 1a the drive wedge 33 is attached to the foot 35 at a 
distance 15 about 1/3 of the width of the foot 35 from the edge of the 
foot which is adjacent the side rail 23 and approximately centrally in 
regard to the length of the foot 35. The purpose of the foot 35 is of 
course to distribute the force applied to the door 11 over a comparatively 
wide area so the drive wedge 33 does not dig into the door 11. 
The drive wedge 33 in this embodiment comprises a portion of a 
substantially circular disk having a circular-arc-shaped edge 32 and two 
straight wedge edges 34 approximately at right angles to each other for 
maximum inward displacement which meet at a vertex 75. The wedge pivot pin 
45 is located adjacent the vertex 75. During its pivoting motion pushing 
the door 11 inward the drive wedge 33 is associated with a guide 51 
attached rigidly to the side rail 23 as shown in FIG. 6. This one-piece 
guide 51 includes an approximately flat guide plate 52 which is 
substantially parallel to the surface of the drive wedge 33 and which is 
positioned so that the circular arc-shaped edge 32 is between it and the 
side rail 23 so that the drive wedge 33 is prevented from swinging away 
from the side rail 23 during operation. It is because of the presence of 
the guide 51 that the edge 32 must be substantially circular arc-shaped. 
The drive wedge 33 is also pivotally connected to a drive rod 29 which is 
movable by the driving hydraulic cylinder 31 so that the drive wedge 33 is 
pivoted toward the door 11 forcing it inward. 
The pivotal attachment of the driving hydraulic cylinder 31 is to the drive 
wedge 33 is shown in detail in FIG. 3. The piston rod 57 of the driving 
hydraulic cylinder 31 has a U-shaped connector 55 attached rigidly at its 
end exterior to the driving hydraulic cylinder 31 with its arms extended 
in the longitudinal direction of the piston rod 57. A connector pivot 54 
is attached between the arms of the U-shaped connector 55. The drive wedge 
33 closest to the driving hydraulic cylinder 31 is pivotally attached to 
the bottom of the drive wedge 33 adjacent the circular arc-shaped edge 32. 
Immediately above the U-shaped connector 55 and the pivotal attachment at 
pivot 54 the U-shaped cross sectioned drive rod 29 is pivotally mounted on 
a drive rod pivot pin 56 on the drive wedge 33. Thus when the driving 15 
hydraulic cylinder 31 extends the piston rod 57 as shown in FIG. 2 and 3 
the drive wedge 33 swings toward the door 11 forcing the foot 35 against 
it and the U-shaped cross sectioned drive rod 29 is forced inward toward 
the door 11 pivoting on the drive rod pivot pin 56 to remain nearly 
vertical. 
Two adjustable braces 25, each of which is of an adjustable width, connect 
the side rails 23. In the preferred embodiment the adjustable brace 25 can 
adjust so that the door forcing apparatus 10 fits doors from 27.5 to 47 
inches wide. Larger or smaller braces can be used to allow the door 
forcing apparatus to fit almost any door. One adjustable brace 25 is 
attached between the side rails 23 adjacent each end of the pair of side 
rails 23 so that when the side rails 23 are braced against the door jamb 
15 there is a large open space which is substantially the size of the 
doorway when the door 11 has been forced. 
In the embodiment shown in FIGS. 1 to 4 each adjustable brace 25 comprises 
a turnbuckle having two oppositely threaded turnbuckle screws 65 and 63 
engaged in opposite ends of an interiorly-threaded center pipe 61. The 
ends of the turnbuckle screws 65 and 63 not engaged in the center pipe 61 
have pivots 69 rigidly attached. These pivots 69 may be short rods and are 
engaged in the pivot eyes 67 which are rigidly attached to the side rails 
23. Thus each adjustable brace 25 is pivotally attached to each side rail 
23 and during storage and transport the adjustable brace 25 can be 
collapsed with adjacent rails 23 pushed together as shown in FIG. 9. The 
pivots 69 only allow the side rails 23 to pivot up or down as in FIG. 9, 
but will support the side rails 23 so that force may be provided to thrust 
them into the door jamb as in FIG. 11. 
An alternative embodiment in which the adjustable braces 25 are bracing 
hydraulic cylinders 91 is shown in FIG. 7. The hydraulic cylinders 91 
allow automatic remote application of a larger bracing force than can be 
provided with the turnbuckle arrangement in the embodiment of FIGS. 1 to 
4. The piston rods of the bracing hydraulic cylinders 91 are each 
pivotally connected to one of the side rails 23 as in the embodiment 
described in the previous paragraph. 
The bracing hydraulic cylinders 91 are connected with a hydraulic pump 83 
and an accumulator or reservoir 81 for hydraulic fluid 81 which also 
supplies hydraulic fluid to the driving hydraulic cylinders 31 for the 
drive rods 29. The accumulator 81 is connected by 15 hydraulic lines 89 
and 87 through equalizer valves 85 20 with the hydraulic cylinders 91 and 
87 respectively. The equalizer valves act to prevent an unequal 
distribution of pressure on the two sides of the door forcing apparatus 
10. 
In the embodiment of FIGS. 1 to 4 the side rails 23 as shown in FIG. 5 have 
an L-shaped cross section. They each comprise one flat side rail piece 24 
which is attached to the adjustable brace 25 and another flat side rail 
piece 22 attached at right angles to it which engages with a beveled edge 
22' between the door jamb 15 and the door 11. Advantageously this side 
rail piece 22 is about 1/16 of an inch. Other embodiments of the invention 
differ in the form of the side rails 23 as shown in FIG. 7a and 7b. In the 
embodiment of FIG. 7a the angle iron piece which comprises the side rail 
23 is reversed so that the side rail piece 22 faces away from the door 
jamb 15 and not toward it. Instead prongs 71 are rigidly attached to the 
side rail piece 24 and extend outwardly from it toward the door jamb 15. 
When the adjustable braces 25 are extended these prongs 71 engage in the 
door jamb 15 and hold the apparatus fixed while it forces the door 11. For 
example outwardly opening doors can be forced this way. In the embodiment 
shown in FIG. 7b the side rail 23 is almost identical with the side rail 
23 in the embodiment of FIGS. 1 to 4. The difference is that the side rail 
piece 22 has recesses 73 cut into it. 
Many methods of attachment may be used in the door forcing apparatus 10 
which can be changed without modifying the character of the invention. The 
flat foot 35 may be provided with an attached comparatively strong pivot 
eye 43 in which a foot pivot 41 rigidly attached to the upper portion of a 
drive wedge 33 adjacent the circular arc shaped edge 32 engages pivotally. 
The drive rod 29 may have a U-shaped cross section so that a drive rod 
pivot pin 56 which is pivotally engaged in the bottom portion of the drive 
wedge 33 may be rigidly attached between the facing arm portions 29',29" 
of the U-shaped-cross-sectioned drive rod 29. This provides an especially 
strong pivotal connection between the drive rod 29 and the drive wedge 33, 
necessary in view of the large forces that must be applied to the drive 
wedge 33 to force the door 11. When the side rail 29 is driven pressing 
the drive wedge 33 with the foot 35 into the door 11, it eventually takes 
a position adjacent the side rail 23 as shown in FIG. 8. Furthermore the 
lower edge of the flat foot 35 pressing on the door 11 is slightly rounded 
off so that the flat foot does not dig into the door 11 as it forces the 
door. 
The side rails are advantageously of a length such that any of a variety of 
doors 11 may be opened. In the case of the embodiment of FIG. 1 this 
length is about 6 feet. 
The operation of the door forcing apparatus 10 is shown in FIGS. 9 to 12. 
When stored the pivotal attachment of both ends of the adjustable braces 
25 allows the side rails 23 to be collapsed. First the side rails 23 are 
moved apart until the adjustable braces 25 are approximately perpendicular 
to both side rails 23 as shown in FIG. 10. This is done as quickly and as 
quietly as possible. Then the adjustable braces 25 are extended forcing 
the side rails 23 to engage the door jamb 15 or to engage between the door 
jamb 15 and the door 11 either by turning the turnbuckle center pipe 61 or 
by pressurizing the hydraulic cylinders 91 as shown in FIG. 11. Ratchet 
type devices and other types of devices can be used to force the side 
rails into the door jambs also. Finally the hydraulic cylinders 31 are 
extended forcing the drive rods 29 upward and toward the door 11, pushing 
the drive wedges 33 toward the door 11 and pressing the feet 35 on the 
facing surface of the door 11 to force it inward, The force that drives 
the drive rod in turn driving the wedges may be obtained through a variety 
of other methods not mentioned, such as magnetic coils, electric motors or 
a ratchet device similar to that used in automotive bumper jacks for 
example. 
It will be understood that each of the elements described above, or two or 
more together, may also find a useful application in other devices 
differing from the type of device described above. 
The invention is not intended to be limited to the details provided above 
and it will be understood that various omissions, modifications, 
substitutions and changes in the forms and details of the device 
illustrated and in its operation can be made by those skilled in the art 
without departing in any way from the spirit of the present invention. 
Without further analysis, the foregoing will so fully reveal the gist of 
the present invention that others can, by applying current knowledge, 
readily adapt it for various applications without omitting features that, 
from the standpoint of the prior art, fairly constitute essential 
characteristics of the generic or specific aspects of this invention.