[0001] The invention relates to a security system for preventing undesirable opening of
a window or a door or the like element being movably mounted in a frame, said system
comprising two strips whose cross-sectional configurations are designed such that
said strips form at least partially interlocking sections, whereby a first strip is
secured with screws to the frame in which said element is mounted, and whereby the
second strip is secured to the element with screws. In the present application the
word frame will be used to indicate a door casing or window casing and any other device
in which a door or window is hinged or can move otherwise. The word element comprises
a door, window or any other element which is mounted in a frame and which can be opened.
The word screw is furthermore used to indicate any other fastening element as well.
[0002] The purpose of a security system of this kind is to prevent that a door or window
is lifted out of the frame by means of a crowbar or other tool in such a manner that
the door or the window can be opened. In the closed condition of the door, the window
or similar element it is necessary for the strips to interlock in such a manner that
movement of the element with respect to the frame is prevented in at least one direction.
This makes it impossible for the element to be lifted from its fastening, as a result
of which it might be opened.
[0003] It is known to secure strips of this type to the element as well as to the frame
with screws. In order to prevent that the strips are removed, which would undo the
security, strips of this type are often fixed by means of special screws, which can
only be screwed up in one direction. Screws of this type cannot be unscrewed in a
simple manner. A drawback of the use of screws of this kind is that it is made more
difficult for the do-it-yourselfer to fit the strips, and that the do-it-yourselfer
will often use ordinary screws after all, which makes it possible to remove the security
strips. Although the unscrewing of the security strips takes some time, as a result
of which some security is still obtained, this security is not optimal.
[0004] Another drawback of the known strips is that it is often difficult to gain access
to the holes in which the fastening screws are to be fitted. In order to improve this
accessibility recesses may be provided in the fastening strips, so that the screws
can be screwed up by means of an ordinary screwdriver. The presence of such recesses
may have an adverse effect on the outward appearance of the strips, whilst in addition
to that extra production costs are involved.
[0005] The object of the invention is to provide a security system, whereby said strips
are designed such that the security system is easy to install, functions optimally
and has an attractive outward appearance.
[0006] In order to accomplish this objective said strips are designed such that the part
of each of said strips in which holes for the screws are provided is free from other
parts of said strips on both sides, in such a manner that the holes are freely accessible
for fitting the screws, and that in the closed condition of said element the part
of each of said strips in which the holes are provided is covered by parts of the
other strip, of the element or of the frame.
[0007] The security system according to the invention can be fitted in a simple manner,
also by the do-it-yourselfer, by means of ordinary screws, because the screws cannot
be removed with the element in its closed position. Ordinary tools may be used for
fitting the strips, because in the open position of the element the screws for fixing
the strips are readily accessible. Because access to the screws is not possible in
the closed conditions of the element, unauthorized persons are prevented from attempting
to remove the screws. Also with screws that cannot be removed the fact that the screws
are visible induces people to attempt to remove the screws after all. Moreover, the
fact that the screws are not visible has a positive aesthetic effect.
[0008] According to another aspect of the invention at least one of said strips may have
an edge portion, in which said holes are provided, said edge portion in the closed
condition of the element being located between said element and said frame. The screws
fitted are thereby not covered by said other strip, but by the element and/or the
frame.
[0009] According to the invention at least one of said strips may furthermore consist of
a U-section having unequal legs, whereby said holes are provided in the longer leg
of said section. The section may be screwed on the frame or the element with its longer
leg, whereby access to the screws is readily possible.
[0010] When the security system is provided with an element opening to the outside, the
strips may be provided in such a manner that they are completely located beyond the
circumference of the element, whereby one strip or both strips may be fixed in the
space between said element and said frame.
[0011] The invention furthermore relates to a method for securing a door, a window or the
like element being movable in a frame against undesirable opening, whereby a first
strips is secured with screws to the frame in which said element is mounted, and whereby
the second strip is secured to the element with screws, whereby the part of each of
said strips in which holes for the screws are provided is free from other parts of
said strips on both sides, in such a manner that the holes are freely accessible for
fitting the screws, and that in the closed condition of said element the part of each
of the strips in which the holes are provided is covered by parts of the other strip,
of the element or of the frame.
[0012] Further features of the invention will be discussed and/or explained in the description
of the Figures and in the claims.
[0013] In order to more fully explain the invention a number of embodiments thereof will
be described hereafter with reference to the drawing.
Figures 1 - 4 show a hinged element, which opens to the inside;
Figures 5 - 7 show a hinged element, which opens to the outside; and
Figure 8 shows a sliding element.
[0014] The embodiments are only diagrammatically shown in the Figures, in which like parts
are numbered alike.
[0015] Figure 1 shows a frame 1 (casing) and a hinged element 2, for example a window. Arrow
3 indicates that the element 2 is hinged at the end not shown, so that the element
2 can turned out of the frame. As in the other Figures the element is shown in its
closed condition in Figure 1.
[0016] According to Figure 1 frame 1 is provided with a strip 4 in the form of a metal section,
which strip 4 is secured in the frame by means of screws 5. The cross section of strip
4 has a substantially U-shaped configuration with two unequal legs, whereby the screws
5 extend through holes into the long leg of said U-section. Window 2 is provided with
a strip 6 in the shape of a metal L-shaped section. Strip 6 is secured to the window
2 by means of screws 7, whereby said screws 7 are fitted through holes in the short
leg of the L-section 6.
[0017] It will be apparent that in the open position of the window 2 the sections can be
readily screwed to the element 2 and the frame 1, and that the strips 4, 6 are configured
such that the screws are readily accessible with a screwdriver. Because in the closed
condition of the window, as shown in Figure 1, access to the screws is not possible,
it is not necessary for the strips to be secured with special screws that cannot be
unscrewed. It will be apparent from Figure 1 that each of the strips covers the screws
with which the other strips is fastened. Since the screws are not visible, an unauthorized
person wanting to force open the window will less readily make an attempt to remove
the strips. After all, he will not be able to see in what manner and in what places
the strips are fastened. Moreover, the fact that the screws are not visible has a
positive aesthetic effect.
[0018] Figures 2, 3 and 4 show embodiments of a window opening to the inside, whereby other
sections according to the invention are used. In all cases it applies thereby that
in the open position of the window 2 the screws are not accessible or even visible.
The object of the strips provided is to prevent that a crowbar or other tool is placed
between the frame 1 and the window 2 in a simple manner in order to open said window,
whereby it is in particular prevented that the window 2 is moved outside the frame
in its plane (a movement of the window 2 to the right in the Figures), so that the
fastening of the window would be rendered inoperative.
[0019] The embodiments shown in Figures 1, 3 and 4 are to be preferred, since strip 6, which
is secured to the door/window 2, is of simple design and is consequently inexpensive
to produce, whilst it can be fitted in a quick manner.
[0020] According to the embodiments of Figures 5 - 7 a window 2, which opens to the inside,
is secured by the strips 4 and 6. In all embodiments the strips are fitted to the
outside of the frame/window assembly.
[0021] In Figures 5, 6 and 7 strip 6, which is secured on window 2 with screws, consists
of a metal U-shaped section, whose legs have unequal lengths. The long leg of the
section is fastened to the end face of the window 2, and that in such a manner that
access to the screw is not possible in the closed position of the window 2. Other
embodiments of strip 4 are shown in Figures 5, 6 and 7, whereby according to the embodiments
of Figures 5 and 6 the fastening screw 5, with which the strip 4 is secured, is located
between the frame 1 and the window 2 in such a manner, that the screw is not accessible
in the closed condition of the window. In the embodiment of Figure 7 the screw 5 is
covered by strip 6 in the closed condition of window 2.
[0022] Figure 8 shows an embodiment for securing a sliding door. The metal strips 4, 6 are
thereby configured such that they can be moved into an interlocking position, whereby
the one section covers the fastening screws of the other section. Also in this case
the presence of the security strips prevents that the door can be forced open easily
by means of a crowbar or other tool, whilst the door 2 is prevented from being moved
perpendicularly to its plane.
[0023] In all embodiments the element 2 may be a door as well as a window, and the strips
4, 6 may be strips made of metal or of any other suitable material. Moreover, instead
of screws 5, 7 also other fastening means may be used, for example nails or pop rivets.
Pop rivets may in particular be used when the frame 1 and/or the element 2 are made
of aluminium.
[0024] In the Figures only a few embodiments of the invention are shown, and consequently
these embodiments of the invention are merely to considered as examples.
1. A security system for preventing undesirable opening of a window or a door or the
like element being movably mounted in a frame, said system comprising two strips whose
cross-sectional configurations are designed such that said strips form at least partially
interlocking sections, whereby a first strip is secured with screws to the frame in
which said element is mounted, and whereby the second strip is secured to the element
with screws, whereby the part of each of said strips in which holes for the screws
are provided is free from other parts of said strips on both sides, in such a manner
that the holes are freely accessible for fitting the screws, and that in the closed
condition of said element the part of each of said strips in which the holes are provided
is covered by parts of the other strip, of the element or of the frame.
2. A security system according to claim 1, characterized in that at least one of said
strips has an edge portion, in which said holes are provided, said edge portion in
the closed condition of the element being located between said element and said frame.
3. A security system according to claim 1 or 2, characterized in that at least one
of said strips consists of a U-section having unequal legs, whereby said holes are
provided in the longer leg of said section.
4. A security system according to any one of the preceding claims, characterized in
that at least one of said strips is completely located beyond the circumference of
the element.
5. A security system according to any one of the preceding claims, characterized in
that at least one of said strips has a substantially U-shaped cross-section, whereby
the holes are provided in the base of the U-shape.
6. A security system according to any one of the preceding claims for an element opening
to the inside, characterized in that said second strips has an L-shaped section, with
screw holes in the short leg, and whereby the long leg is flat and extends at a right
angle or a slightly smaller angle.
7. A security strip to be used in accordance with any one of the preceding claims.
8. A method for securing a door, a window or the like element being movable in a frame
against undesirable opening, whereby a first strips is secured with screws to the
frame in which said element is mounted, and whereby the second strip is secured to
the element with screws, whereby the part of each of said strips in which holes for
the screws are provided is free from other parts of said strips on both sides, in
such a manner that the holes are freely accessible for fitting the screws, and that
in the closed condition of said element the part of each of the strips in which the
holes are provided is covered by parts of the other strip, or of the element or of
the frame.