Electrical conductor element

An electrical conductor element in the form of a flexible or rigid sheet is provided for detecting attempts to break into a space where valuables or money are being stored, such as a strongroom or the coin container of a slot machine. The base material of the element is in the form of a woven or non-woven material or of plastic sheeting, and the electrical conductor is in the form of wire such as enameled copper wire for electrical connection with an alarm system. The conductor is secured in place by stitching, that is to say the wire is either formed into penetrating stitches by being fed from the needle or shuttle of a sewing machine or it is fed from a stationary part of the sewing machine so as to be fixed in place by stitches or conventional textile yarn or thread. When the conductor is interrupted by drilling, sawing or the like the alarm system is activated.

BACKGROUND OF THE INVENTION 
The invention relates to an electrical conductor arrangement for security 
purposes on areas of safes, strongrooms, slot machines and other 
containers for money and valuables, in the form of a sheet material 
bearing wiring as electrical conductors, whose lengths are arranged 
alongside each other and adapted for connection with a security alarm 
system. 
In order to prevent theft from safes, strongrooms, and slot machines by 
sawing, drilling, using brute force and other methods, it is an accepted 
practice to lay electrical conductors on the inner or outer surfaces of 
the walls of the enclosure where the money or valuables are held and to 
connect such conductor with an electronic alarm system which supplies an 
electrical current to the conductor to detect any interruption therein. In 
the event of violence being exerted on the conductor so that it is 
interrupted the alarm system is tripped. 
Such an alarm system is described in the German patent publication DE-A 
2,148,570, in which the electrical conductor is to be secured in place by 
bonding or pressing or it is to be produced on the base by printing. 
This method is slow and expensive, the reliability of the attachment not 
being very high so that this type of attachment has hardly proved 
successful in practice. 
SHORT SUMMARY OF THE INVENTION 
One object of the present invention is to provide an electrical conductor 
arrangement for security alarms for use on areas of walls etc. which may 
be economically produced. 
A further aim of the invention is to provide such a conductor arrangement 
which is of superior quality. 
In order to achieve these or other objects appearing herein the electrical 
conductor is attached by stitching, that is say by forming the conductor 
into stitches linking it with a base or by using stitches of thread to sew 
it in place on such base.

DETAILED ACCOUNT OF EMBODIMENTS OF THE INVENTION 
In the case of the working embodiments of the invention depicted in FIGS. 1 
and 2 the purpose is to provide a security system for areas, such as wall 
surfaces of a safe or the like, and this is ensured by the provision of a 
thin flexible sheet of electrically insulating base material 1, as for 
instance in the form of sheeting of bats, that is to say non-woven 
material, of a woven material, or of a film, on which an electrical 
conductor 2, such a enamelled copper wire is attached by sewing so that 
the conductor runs in parallel lengths or turns, such attachment by sewing 
being for instance by using the wire as one thread coming from a moving 
part of sewing machine (either as the upper thread from a stationary 
bobbin or from the shuttle) or for instance so that the loops produced in 
the upper or lower thread hold the wire and are so large that the wire or 
electrical conductor is applied in a straight form and is only bent when 
the end of a length is reached. Then the wire 2 comes from the sewing 
machine foot so that a thread 5 is trained around it and holds it in place 
by forming stitches over the wire 2, this being shown in FIG. 3. For 
attachment of the wire 2 it is possible to use zigzag stitches extending 
over the wire 2. 
The sewing of the wire or electrical conductor to the base material may be 
controlled rapidly and automatically by a programmable sewing or stitching 
machines or embroidering machines, it being possible to achieve a very 
firm attachment of the wire in place and any desired form of gap may be 
produced as shown in FIG. 2 at 8. 
The electrical conductor element consisting of the electrical conductor 2 
and the base material 1 for a security alarm system for application to 
areas of walls etc. may be produced in large sizes owing to the use of 
automatic production machines at a low cost. 
The electrical conductor 2 applied in this manner only has a beginning 3 
and an end 4 and is between the beginning and the end is continuous. 
In order to facilitate mounting of the electrical conductor element it is 
possible to apply double-side adhesive film 6 as indicated in FIG. 4 to 
the base. This makes possible simple adhesive attachment of the prepared 
electrical conductor elements to the wall of the valuables container such 
as a strongroom or a slot machine in which money is collected. The 
electrical conductor elements may be rendered impermeable to water by the 
application of liquid wax thereto and it may also be given a screeded 
finish with concrete or the like to stiffen it. 
Another possibility of facilitating mounting of the element is a method in 
which for each side of the wall, floor or ceiling to be covered a separate 
electrical conductor element is produced which is mounted on a stiff 
carrier 7 such as a piece of plasterboard so that the board with the 
element attached thereto as a component of the security alarm system may 
be arranged in the strongroom or the like, this being indicated in FIG. 4. 
When the security alarm system is turned on a current pulse is caused to 
flow through the continuous wire 2 from the beginning to the end thereof 
by the electronic circuit of the alarm system. If the wire 2 is 
interrupted owing to the activities of a thief using a saw or a drill or 
attempting forceable entry in some other way, a drop in the current 
through the wire 2 will be caused and this will be detected at the end 4 
of the wire 2 so that an alarm will be raised by such electronic circuit, 
which may be designed in accordance with the initially mentioned prior art 
.