US 3851602 A
The safety box or the like, is, in particular, suitable for transportation, has imbedded in its side wall a number of randomly arranged electrically isolated detector loops which, when cut or otherwise destroyed, trip an alarm or trigger destruction of the contents of the safety box. These randomly arranged closed conductor loops can be associated with adjacent conductors, with a voltage being applied between each loop and the adjacent conductor. A timing circuit may be provided to operate, in case of a breaking in of the box, to trip destruction of the box quicker than the box can be broken into. A temperature supervising device is provided to assure a reliable operation of all the detector devices and current sources, and can also respond in case the box is attempted to be cut open by a torch.
Claims available in
Description (OCR text may contain errors)
Unit Sttes 1191 1111 3 5L62 Lamping Dec. 3, 1974  SAFETY BOX OR THE LIKE FOREIGN PATENTS OR APPLICATIONS Inventor! Wolfram Lamping, 95,683 7/1924 Austria 109/41 Munich/Waakirchen, Germany  Assignee: G.A.0. Gesellschaft fur Automation Prima'y Examiner-Dennis Taylor und O i ti mbH, Munich Attorney, Agent, or Firm-McGlew & Tuttle Germany 22 Filed: Feb. 24, 1972  f l The safety box or the l1ke, Is, In part1cu1ar, suitable for [21 l PP 223,867 transportation, has imbedded in its side wall a number of randomly arranged electrically isolated detector  Foreign Application Priority Data loops which when cut or otherwise destroyed, trip an Feb 23 1971 Austria 1522/71 alarm or trigger destruct1on of the contents of the safety box These randomly arranged closed conductor loops can be associated with adjacent conductors, (g1 l()9/2E36510g;(3)(lJ t with a voltage being applied between each loop and 58] Fieid 38 24' the adjacent conductor. A timing circuit may be provided to operate, in case of a breaking in of the box,
340/272 161/143 200 to trip destruction of the box quicker than the box can be broken into. A temperature supervising device is  References cued provided to assure a reliable operation of all the de- UNITED STATES PATENTS tector devices and current sources, and can also re- 126,289 4/1872 Guernsey 109/41 UX spond in case the box is attempted to be cut open by 181,078 8/1876 Larned 1.. 109 41 X a torch. 483,728 10/1892 Stromberg 109/41 1,686,457 10/1928 Mcc11m61 340/273 13 Clams, l2 Drawmg Flgulfes @EZE 31974 M my 6,
l /fl/ ///////1// banknots 6 s Fig. 2
PATEML BKC 3:914 I 3851.602
SHEEIEBFG Fig. 4
FIELD AND BACKGROUND OF THE INVENTION The present invention relates to a so-called safety box, i.e. to a container aimed at protecting the possessions contained therein from unauthorized access. Such types of boxes are used in particular for the transportation and safe-keeping of all kinds of securities, such as bank notes and share certificates, as well as other documents, working drawings, contracts, and similar papers.
From the fields of strong-box (safe) and intrusiondetector system engineering there is already known a great number of various protective measures. According to one principle of protection, the walls of the boxes or rooms are protected from burglary by using steels which are particularly difficult to be worked at, such as sintered steel, or fillers or inlays of corundum concrete between the jacketed walls. Other well-known safety systems known from the fields of intrusion-detector engineering use jacketed walls for surrounding a pressure space, so that, with reference to variations in pressure, it can be detected whether attempts are being made to break into the room or space by the application of force. There are also known safety systems employing current-controlled conductors built into walls or glass panes and which are likewise capable of reporting any breaking-in by the use of force. Irrespective of the technical types of embodiments, all of these protection systems are based on the fact of either rendering more difficult the unauthorized breaking into the rooms to be secured, or to report any attempts at forced entry.
The deficiencies of a mechanical intrusion detector or burglar alarm system based on the strength of the employed material are obvious. In particular the thus protected safety boxes are extremely heavy and expensive, and almost unsuitable for transportation.
Intrusion detector systems providing a burglar alarm are primarily unsuitable for application to portable boxes or containers, because attempts for opening them are usually made at some unknown location. Moreover, the efficiency of any burglar alarm system is fundamentally substantially restricted by the fact that it serves its purpose only in cases where there is available a sufficiently quick reaction. Accordingly, deficiencies are involved which are mostly not at all avoidable for organisational reasons. But also the mechanical protection of the portable containers or boxes is not particularly sufficient, because they can always be opened somehow with the aid of suitable means. The fact that the number of money transport robberies, for example, is comparatively much higher than the number of burglaries into a stationarysystem, shows up these deficiencies very clearly.
SUMMARY OF THE INVENTION The invention, therefore, is based on the problem, by avoiding the aforementioned deficiencies, of providing in particular a portable safety box. The invention itself is based on the aforementioned recognition that a mechanical forced entry into the room to be protected is practically always possible, and that the burglar alarm may often be too late.
In starting out from this recognition, the fundamental idea of the invention is based on making useless or destroying either completely or partly the contents of the room or box to be protected in the case of an unauthorizedattempt to break in. For detecting such attempts at burglary there may then be used means known per se from the fields of instrusiondetection engineering but which, according to further features of the invention, are in particular adapted to the basic idea of invention. Moreover, for initiating the making useless or destruction of the contents to be protected, there may also be used means known per se from other related fields of application.
The invention utilizes the known principle of laying out or imbedding into the walls of the safety box closed-circuit supervisory conductor loops. Since, however, such loops in principle are easily and quickly bridged, so that the alarm device is thus put out of service, in accordance with the invention the conductor loop or the conductor loops are so arranged as to form many iregular windings which are electrically isolated from each other. In case of destruction or interruption of the conductors or conductor loops, either an alarm is tripped, in a known manner, or the contents of the safety box are destroyed or permanently modified. Due to the chaotic arrangement of the conductor loops,
bridging thereof is impossible because the burglar cannot see in which way he must bridge the loops.
The safety can be improved still further if, in addition to the closed conductor loop or loops, there are also arranged open conductors, having a voltage applied thereto, which are either twisted with the conductor loops or arranged very close to the conductor loops. With this arrangement, it is nearly impossible to avoid producing a short circuit during intrusion attempts.
In accordance with the invention, an effective and important further increase in safety can be obtained by providing a timing circuit effecting a relation between a safety factor and destruction, by attaining, in the case of an attempt to break into the box, destruction of the contents quicker than the time required for opening the box.
In accordance witha further embodiment of the invention, a temperature supervision is provided, in addition, and assures a reliable operation of all devices and current sources. This temperature supervision can also respond to trigger an alarm or the like when an attempt is made to open the box by torch cutting.
For an understanding of the principles of the invention, reference is made to the following description of typical embodiments thereof as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:
FIG. 1 is a schematic sectional view of a novel safety box embodying the invention;
FIG. 2 is a sectional view showing part of a foil, comprising a conductor loop, attached to the inside wall of the box;
FIG. 3 is a view similar to FIG. 2 but illustrating a simplified section;
FIG. 4 is a schematic wiring diagram of a closedcircuit supervised double-conductor loop;
FIG. 5 is a partial plan view of a foil upon which a conductor has been evaporated;
FIG. 6 is a schematic wiring diagram of a circuit for effecting the closed-circuit supervision of an individual loop;
FIG. 7 is a schematic wiring diagram of a circuit for effecting the closed-circuit supervision of a double loop;
FIG. 8 is a combined schematic sectional view and schematic wiring diagram illustrating a depreciating device in accordance with the invention;
FIG. 9 is a perspective view illustrating the safety box opened so that its interior is visible;
FIG. 10 is a perspective view illustrating the walls of the safety box, with a foil thereon, as disconnected rnechanically from each other;
FIG. 11 is a combined exploded perspective view, schematic wiring diagram and sectional view illustrating the foils with the conductor loops and their connection to the evaluating circuit and to the depreciating device; and
FIG. 12 is a view similar to FIG. 7 but illustrating the loops as loops rather than as resistances.
DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 schematically shows the new safety box. 'It consists of the housing 1, with the cover 2 and the lock 3, the timing circuit 5, the depreciating device 6, the box contents 7 and the evaluating circuit 8. Finally there is provided the connection 4 serving to connect the cover 2 and the housing I. with one another in such a way as to obtain a closed safety system.
FIG. 2 shows a part of the walls 9 of the safety box, with the interior surfaces of these walls being lined with electrically non-conducting foil 10 into which are imbedded electrical conductors l2. Foil 10 preferably is formed from a plastic composition material having special properties, as will be described hereinafter. It will be noted from FIG. 2 that the conductors 12 whose terminals 11 extend to the timing circuit 5 or to the supervisory circuit 8, respectively, are embedded in the foil 12 in a confused or, irregular as possible, and vague or disorderly manner. The significance of this arrangement will be explained in greater detail with reference to FIG. 3.
The possibility of effecting unauthorized access to the inside of the box would reside in successively lifting the conductors and bridging them by means of external loops and thus providing the prerequisite for getting to the inside at one point. For example, if the conductors were lifted at zone 16 and thereafter at the neighboring zone 14, the zones 14 and 16 might be electrically bridges thus rendering ineffective the conductor lying between these zones. If now, as a next step, the zones 13 and would be cleared and bridged, this step would already be superfluous as lying within the ineffective loop. However, since it is impossible to recognize this fact owing to the confused arrangement of the conductor loops, this would involve the performance of an arbitrary number of useless operations.
Relative thereto it is still to be considered that actually it is not possible at all to bridge the conductors. On
one hand the foil is non-transparent and, on the other 7 hand, in the case of correspondingly thin conductors, there will be obtained such a high number of conductors, per unit of volume, that any'attempt, of the kind described hereinbefore, would be condemned to be a failure from the beginning. For example, when using a commercially available copper wire of 0.025 mm diameter there would be obtained a density of 400 conductors per mm.
FIG. 4 shows a particularly favorable arrangement of such closed-circuit supervised conductors. The conductors 12 are arranged to extend close to one another, with a current flow being registered by the indicator 18 in the closed conductor loop via the source of current 17, while no current flows in the open loop. Since the open and the closed loop are positioned closely adjacent each other, it is practically impossible not to cause a short circuit between the two of them. In this case, however, there results the difference between the insulation'resistance of the foil and, in the most unfavorable case the resistance of the two series-connected conductor loops which lends itself particularly well for evaluation purposes. This would also exclude any probable attempts of drilling or boring in a liquid of the conductive type.
FIG. 5 shows the foil 19 on which the conductors 20 are either evaporated or deposited by way of etching. Several such foils may be stuck on to one another. Supervision may be carried out according to FIG. 4. On the other hand, conductors may also be evaporated in an areal manner on both sides of the foil 19 for permitting in this way a capacitive evaluation.
By carefully selecting the properties of both the foil and the conductor materials shown in FIGS. 2 to 4, the efficiency of the safety system can be further increased. Thus, it is appropriate to use a non'transparent plastics material as the embedding material, Le. a plastics material having the same or a higher melting point than the insulation material of the conductors. In this way it is achieved that a short circuit will result compulsorily in the'event of any cutting or melting attempts. Likewise it is possible to use very brittle embedding materials which would break responsive to being worked upon mechanically, thus likewise destroying the conductor loops as embedded therein.
Moreover, it is possible to use embedding materials having the same acid resistance as the lacquer insulation of the conductors. This would likewise cause a short circuit when trying to dissolve the insulation. Further properties of the materials might be of the chemical kind, such as decomposition when coming into contact with air, and the like.
Another property when using foils, may be that the adherence of a conductor strip on the foil is smaller than the adhesion which is produced when sticking or cementing one foil on to another one by using a certain kind of adhesive. In this way it can be achieved that the conductor lead of the lower foil is compulsorily torn off when removing the top foil.
The principle of supervising the conductor loops is shown in FIG. 6. The conductor 24 represented as a resister, is controlled or checked via the Darlington amplifier 24. In in the event of a resistance variation, a signal variation 23 will result at the output 22 serving to trigger the depreciating device 6.
In an arrangement employing one open and one closed conductor loop according to FIG. 4, the evaluation may be carried out in a similar way. FIG. 7 shows one possible type of circuit comprising two complementary Darlington amplifiers for very long and, consequently, high-resistive conductor loops which will be easily understood with reference to FIG. 6.
As will result from the examples described hereinbefore, a source of current is required in any case. Apart from this, and with respect to the examples employing conductor loops, there is required an electronic utilization device which likewise has to be supplied with current. In order to safeguard an unobjectionable operation of these electrical units, there is still provided a temperature control reacting against the range of ex- .cessive temperature or insufficient temperature respectively, which would prevent the switch from functioning properly, and which thus excludes these ranges.
In order to mention a simple example, it is assumed that both the source of current and the electronics operate objectionably at temperatures ranging from -30 to +l00 C. in this case the temperature control is so designed as to respond upon reaching one of these limit values for actuating the depreciating device, thus safeguarding the proper functioning of the safety box under all-circumstances. For effecting the temperature control it is possible to use well-known means, such as bimetal, or the like.
Another functional unit of the safety box consists of the timing circuit 5, for which known devices of the electrical or mechanical type may be used. This unit forms an important part of the novel safety box, and serves to make it absolutely unattackable.
When assuming, for example, that the box is to be opened by an unauthorized person by bridging the individual parts of the conductors, there will have to be taken into account a minimum time required for carrying out this bridging operation, with this being dependent upon both the employed materials and the conductor density per unit of volume. lf now, prior to the lapse of this minimum period of time, the depreciating device 6 is activated by the timing circuit 5, the box cannot be opened successfully, because it will prove that the contents thereof have already been destroyed or made useless prior thereto.
Based on the correlation between the minimum period of time and the conductor density, the latter may be adapted to the given problem, i.e. it can be made smaller and, consequently, more simple in cases where only short-lasting transportation is involved. For ascertaining the correlation factor between time and conductor density one may start from the fact that the unauthorized user is operating under optimum conditions and has tools at his disposal, so that it is very easy to calculate how much time would be required under optimum conditions for overcoming the safety system.
The depreciation or destruction of the contents of the safety box will now be described, by way of example, with reference to FIG. 8. 0n principle, it is possible to carry out the depreciation or destruction either mechanically or chemically. Relative thereto it is alone decisive for what purpose the safety box is to be used in the end. For example, it is deemed to be completely sufficient, in the case of bank notes, to achieve a typical irreversible identification, which might be in the form of stains caused by burning or inking, whereas, in the case of any possible transportations of secret code documents, only a complete destruction of the papers would bring about the desired success. For this reason only some of the principles have been picked out of the great number of known possibilities.
FIG. 8 schematically shows a coloring (inking, dyeing) device. Upon closing of the switch 25 by the evaluating circuit 8, the circuit is completed across the battery. Chopping of the battery current is effected in the chopper 26 and stepping up of the current is effected by the ignition or sparking coil 27. Via the discharge or sparking gap 28 there is effected the firing of thesolid or liquid propellant charge 29. The pressure caused by this detonation opens the partition wall 32 and presses the reaction agent 30 through the predetermined breaking points 31. These predetermined breaking points, for example, are designed in the form of the well-known bursting diaphragms.
Owing to the high pressure caused by the reaction agent, it is assured that the contents of the box are rapidly and intensively penetrated. When using dyestuffs as the reagent, it is appropriate to use organically soluble colors of high intensity, such as butanol, Zapon or Sudan colors which are treated or mixed with substances dissolving the paper coating or sizing for increasing the speed of penetration into the paper fibres.
It is also possible to employ gases, especially in cases where special labels or indications are used on the contents of the box, such as heavy metal salts (activators) or the like, or else in cases where the base is treated or mixed with certain chemicals.
The use of acids is likewise possible for obtaining the desired reaction. It is the aim in any case to obtain a typical, well visible or recognizable and irreversible change of the contents of the safety box.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will'be understood that the invention may be embodied otherwise without departing from such principles.
The depreciating device can be replaced or completed by conventional types of alarm, such as sirens, transmitters, light signals, and the like.
i What is claimed is:
1. In a portable safety box for transporting valuables, of the type including intrusion-resistant closure walls having incorporated therewith externally invisible electric conductor supervisory loops, connected in a closed circuit with a source of potential and an intrusion responsive device, operable, when a conductor is interrupted, to activate the intrusion responsive device, the improvement comprising, in combination, plural irregularly and randomly arranged conductor loops incorporated with each wall of said box and arranged closely adjacent each other, and each forming a closed circuit with a source of potential and said device; whereby said device is activated responsive to interruption of any one of said loops; and means operatively associated with said device and operable, responsive to activation of said device, to at least substantially modify the contents of said safety box in a lasting manner.
2. in a portable safety box for transporting valuables, the improvement claimed in claim ll, further including, in incorporation with each wall, plural irregularly and randomly arranged open conductors forming open conductor loops and each arranged closely adjacent a respective closed conductor loop; and a source of electric potential connected to said open loop conductors to apply an electric potential thereto.
3. ln a portable safety box for transporting valuables, the improvement claimed in claim 1, in which said electric conductors are imbedded in a plastic material foil adhered to the inner surface of the associated wall of said safety box.
4. In a portable safety box for transporting valuables,
tric conductors are evaporated onto said plastic material foil.
5. In a portable safety box for transporting valuables, the improvement claimed in claim 3, in which said electric conductors are etched onto said plastic material foil. v
6. In a portable safety box for transporting valuables, the improvement claimed in claim 3, in which said electric conductors are imbedded between superposed plastic material foils adhered to each other.
7. In a portable safety box for transporting valuables, the improvement claimed in claim 6, including a first adhesive adhering the superposed layers of plastic material foil to each other, and a second adhesive adhering said electric conductors to said plastic material foils; said second adhesive being stronger than said first adhesive; whereby, upon tearing of said layers of plastic material foils apart, said conductors will be broken.
8. In a portable safety box for transporting valuables, the improvement claimed in claim 3, in which said electric conductors are evaporated onto both surfaces of said plastic material foil, whereby variations in the capacity between the two electric conductor layers may be utilized in addition to activate said device.
9. In a portable safety box for transporting valuables, the improvement claimed in claim 3, wherein said electric conductors are insulated, with the dielectric proptents of said safety box.
erties of the insulation of said electric conductors and of said plastic material foils differing from each other.
10'. In a portable safety box for transporting valuables, the improvement claimed in claim 3, wherein said electric conductors are insulated, the temperature properties of the insulation of said electric conductors and of said plastic material foil differing from each other.
11. In a portable safety box for transporting valuables, the improvement claimed in claim 3, wherein said electric conductors are insulated; the insulation of said electric conductors having the same resistance to acid as said plastic material foil.
12.'In a portable safety box for transporting valuables, the improvement claimed in claim 1, including a timing circuit operatively associated with said device and with said last named means and set to activate said last named means to at least substantially modify the contents of said safety box in a lasting manner, at a rate sufficient to effect such modification before an unauthorized intrusion into said safety box can be completely effected.
13. In a portable safety box for transporting valuables, the improvement claimed in claim 1, in which said last named means effects destruction of the con-