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(11) | EP 0 429 414 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Device for monitoring the displacement of a protected article, in particular a banknote bunch |
| (57) A device for monitoring the displacement of a bunch of banknotes protected in a bank
comprises, concealed in said bunch, an electric battery (1), a coded controlled frequency
electromagnetic wave receiver, an actuator element (2) arranged between the battery
and the receiver and an alarm assembly (8) and further comprises, concealed along
an outlet path (P₁--→P₂) to be covered by the bunch stolen by a robber to the exit
of a bank, means for transmitting the electromagnetic waves, the actuator including
a vibration switch (2) adapted to close a circuit on the battery (1) as it is vibrated
by the displacement transmitted to the banknote bunch, the receiver being designed
so as to actuate the alarm element exclusively if it receives from the transmitting
means two different electromagnetic waves, offset from one another and suitably coded,
each having a dedicated frequency f₁, f₂ and being received according to a given sequence. |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a device for monitoring the displacements of a protected article, in particular a banknote bunch, to energize an alarm device if said article, protected in a first place, is removed from this first place and brought to a second place.
[0002] In the following disclosure the following terms should be intended as follows: a protected article or simply "an article", comprises any articles having a given value, such as a banknote bunch, a precious article or document casing, a great size document and so on; the first place means a drawer or the like arranged at a counter of a bank, a jeweller window, a document bearing cabinet, a first zone of a motor vehicle provided for transporting value articles and so on; the second place is a bank room communicating with the outside environment, a shop or an office or a portion of a building, a second zone of said motor vehicle and so on; a dissuasive and alarm action involves a device or an action emitting sounds, light signals, radio signals, fumes, aggressive or coloring chemical substances and so on, either individually or in combination; a robber is a person or person set robbing the protected article; the restrained outlet path is the path to be covered by the robber inside the second place in order to exit the place in which the article is protected.
[0003] The Italian patent No. 976,929 pertaining to the prior art in this field, discloses controlled frequency electromagnetic wave transmitting and receiving devices which operate to: energize the alarm device associated with the protected article to put it in a pre-alarm condition as said protected article is removed from a first place; enable the alarm device as the second article is arranged in a second place; actuate the alarm device as a given period of time is elapsed from the time in which said article has been removed from the second place; disenergize the alarm device if the article is recovered to the second place before said period of time is elapsed.
[0004] The main drawbacks of these known devices are as follows: there is necessary a magnetic assembly to be associated with the protected article in order to hold the alarm circuit in a disenergized condition, and said magnetic assembly can be easily seen and affected by the robber, a quick discharging or power loss of the battery associated with the protected article; the possibility of an undesired operation because of the transmission of waves having a like actuating frequency by electromechanic and electric apparatus such as calculators, copier machines, printers and so on arranged near the protected article; the possibility of actuating the alarm device inside a second place with a great danger for the persons present in this second place. Actually, all of the known protecting systems of the above mentioned time actuate the alarm device as the protected article is removed from the zone covered by the electromagnetic field, and this can occur both outside and inside of the protected place. For example, in the case of a robbery in a bank, if the robber, instead of exiting the bank, would enter again, for example since it is disturbed by polcemen or because of other reasons, then he could abandon the electromagnetic field and, accordingly, the alarm device would be actuated by the bank clients and clerks with a great consequent danger because of a possible reaction of the robber.
SUMMARY OF THE INVENTION
[0005] The main object of the present invention, as it is claimed in the accompanying claims, is to overcome the above mentioned drawbacks and solve the problem of providing a safety device which is not affected by electromagnetic waves having a frequency different from that of the intended controlling electromagnetic waves or by accidental operations by the user.
[0006] In order to solve the above mentioned object, the device according to the invention provides for the use of the following elements, preferably concealed inside the protected article:
[0007] at least a power supply electric battery, an electromagnetic wave receiver supplied by said battery, an actuator adapted to close an electric circuit between said battery and said receiver and an alarm device controlled by said receiver; and, concealed along the restrained path: means for transmitting said electromagnetic waves.
[0008] According to the invention, said actuator comprises a vibration switch and said receiver is adapted to actuate or energize said alarm device as said vibration switch closes said electrical circuit upon vibration thereof; said receiver successively receiving at least two electromagnetic waves each having a dedicated set frequency and a recognizing code, and said electromagnetic waves being received with a preset sequence. Preferably, the means for transmitting said electromagnetic waves comprise an antenna for transmitting each electromagnetic wave, and each antenna is adapted to direct its electromagnetic wave according to a preset direction, so as to cause said receiver to receive each electromagnetic wave at a corresponding preset position of the path followed by said receiver.
[0009] A main advantage of the device according to the present invention is that this device is held in a disenergized condition with the protected article in an at rest condition, whereas it is preset for receiving the alarm actuating waves as the protected article is displaced; moreover, the device is also held in a disenergized condition if the protected article is brought again inside the second place; a further advantage being that the subject device is not negatively affected by a possible discharging of the battery.
[0010] In the following disclosure, the protected article will comprise a banknote bunch and two electromagnetic waves will be used, and, more specifically, one for supplying a code signal having a frequency f₁ and the other for supplying a code signal having a frequency f₂.
[0011] It should be apparent that the vibration switch operates to prevent the battery electric circuit from being closed as the banknote bunch is at a rest condition or is displaced within a preset safety range, that is with such a small displacement not sufficient to cause said switch to vibrate to close the battery circuit; as the displacement transmitted to the banknote bunch exceeds said safety limits, the vibration switch will cause said circuit to be closed so as to energize the receiver. The receiver, in particular, is so designed as to energize the alarm device exclusively if said receiver receives at least two time spaced electromagnetic waves, each of which has a dedicated recognizing code and frequency, respectively f₁ f₂, said electromagnetic waves being received according to a set sequence, for example the wave having the frequency f₁ being followed by the wave having the frequency f₂. Thus, it is assured that the alarm device will not be actuated if the robber, bearing the protected article, exits the second place and then re-enters again, within a given time period t₂. In this case, the sequence of the received frequencies would be f₁ - f₂ - f₁ and an appearance of the frequency f₁ after the frequency f₂ within said time period t₂ would disenergize the device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Further characteristics and advantages of the device according to the present invention will be disclosed in a more detailed way hereinafter with reference to a preferred, though not exclusive, embodiment thereof which is illustrated, by way of an indicative but not limitative example, in the accompanying drawings, where:
Figure 1 is a schematic view showing a room in which there is arranged a device according to the present invention;
Figure 2 is a block diagram of the element assembly included in a banknote bunch;
Figure 3 is a block diagram of transmitting means associated with the device according to the invention;
Figure 4 is an electric diagram of the element assembly concealed in the banknote bunch;
Figure 5 is a diagram showing possible alternatively transmitted signals; and
Figure 6 is an electric diagram of a self-test or diagnosis device according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] Figure 1 shows a hall H of a bank which can be accessed from a road S through the two safety doors D₁, D₂. The bench B comprises some doors for the customers and a cash door DE where, in a box C there are arranged a plurality of banknote bunches, in one of which there are concealed the electromagnetic wave receiver and portions associated therewith, as it should be apparent with reference to figure 2. The box C defines the aforesaid "first place" and the area L encompassing in a closely spaced relationship the two mentioned safety doors represents the aforesaid "second place".
[0014] Near the above mentioned safety doors there are arranged two antennas A₁, A₂, each of which is associated with a transmitter; more specifically, the antenna A₁ is so arranged as to irradiate an electromagnetic wave having the frequency f₁ through a first controlled area F₁ comprising the first safety door D₁, the antenna A₂ being arranged so as to irradiate the electromagnetic wave having the frequency f₂ through a second controlled area F₂ which includes the second safety door D₂. The two mentioned areas are arranged adjacent one another but they do not overlay onto one another.
[0015] In order to better understand the operation of the device being disclosed and the showing of figure 2, there is represented the action of a robber which has removed a banknote bunch from the device and is moving through the releasing path P₁--→P₂. As soon as the banknote bunch is removed from the box C, the vibration switch held in the bunch will operate said receiver; the robber is directed to the road S and is entering the first place and, in particular, the first controlled area F₁ in order to pass through the first safety door D₁; the alarm is still in a not actuated condition; then, the robber passes to the second controlled area F₂ in order to pass through the second safety door D₂, but the alarm is still disenergized; if the robber remains on the path S for a time greater than the programmed time t₂, then the alarm will be energized; if the robber enters again the second place by passing through the second door D₂, and possibly the first door D₁ too, before the elapsing of said time t₂, then the alarm will be in a disenergized condition and the device will be in the condition it had immediately after the robbery of said banknote bunch from the box C.
[0016] Figure 2 shows by solid lines the power supply lines and by thin lines the control signal paths. The figure shows the assembly of the portion concealed in a banknote bunch, not shown, comprising:
_ an assembly 1 including four high performance batteries (1.25 V - 200 mA/h) supplying the input of a vibrating witch 2 (as is known this switch can comprise a displacement detecting circuit actuated by a sensor including a coil spring having one end mechanically and electrically coupled on a fixed base; the other end, suitably counterweighted by a metal mass, is responsive even to very small inertial forces produced by a movement transmitted to said banknote bunch so as to vibrate and contact a suitably spaced electrical contact). The mentioned electrical contact is coupled to the input of
_ a timer with a power supply buffer 3 (which will be hereinafter simply called first timer 3) adapted to energize the other downstream portions up to the expiring of a time t₁ from the time at which the last useful pulse has been sent from the vibration switch 2 and adapted to interrupt the energizing of this downstream portions unless that, upon the elapsing of said period t₁, the timer 3 receives another energizing pulse from said vibration switch 2. As the first timer 3 is actuated, it will be power supplied, in the meanwhile:
_ a circuit 4 for detecting the electromagnetic field and amplifying the detected signal;
_ an assembly including two decoders 5 each of which is adapted to recognize or detect a given coded frequency, respectively f₁ of 1,200 Hz, and f₂ of 2,000 Hz;
_ a logic assembly 6 for time detecting the two above mentioned coded frequencies according to a control logic comprising, sequentially, the following steps depending on the path of the bancknote bunch robbed by the robber::
a) receiving the electromagnetic wave having the frequency f₁, with no energizing and storing of this condition;
b) exiting the field of the electromagnetic wave having the frequency f₁: preserving of the above mentioned storing and no energizing;
c) receiving the electromagnetic wave having the frequency f₂: no energizing and storing of this condition;
d) exiting the field of the electromagnetic wave having the frequency f₂: preserving of this condition and energizing of a second timer 7 adapted to count a time t₂.
[0017] After the step d), two different conditions can alternatively occur:
e₁) energizing the alarm 8 at the expiring of the time t₂,
or:
e₂) receiving the electromagnetic wave having the frequency f₂ and accordingly clearing the second timer 7;
e₃) exiting the field of the electromagnetic wave having the frequency f₂ and then receiving of the electromagnetic wave having the frequency f₁ and then clearing from the store of the electromagnetic wave having the frequency f₂,
e₄) exiting the field of the electromagnetic wave having the frequency f₁, without receiving the electromagnetic wave having the frequency f₂ and accordingly returning to the condition immediately preceding the above mentioned step a).
[0018] _ A flag 9 for indicating that the battery charge level is under a given threshold value. This flag is operated by said vibration switch 2 as an operator displaces said banknote bunch. If the batteries are suitable charged it does not occur any event; otherwise a light or acoustical signal AA signals to the operator that the battery charge is exhausted.
[0019] Figure 3 shows the portions of the transmitter so arranged and concealed that the transmitted signals can be received at said second place. The transmitter comprises:
_ a regulated power supply 10 which, coupled to an outer main 220 V - 50 Hz provide at an output a DC voltage at 18 volts and a maximum current of 2 A,
_ a buffer battery assembly 11, the batteries of which are always held under charge and which operate as the main voltage fails;
_ a first generator 12 provided for generating a first signal having a frequency f₁ = 1200 Hz,
_ a first power amplifyer 13 which receives and amplifies said first signal and transmits it through an antenna 14,
_ a second generator 15 for generating a second signal having a frequency f₂ = 2,000 Hz,
_ a second power amplifyer 16 which receives and amplifies said second signal and transmits it through an antenna 17,
_ a safety unit 18 for monitoring the proper operation of all of the portions of the transmitted signals in order to detect and indicate, for example by a display or buzzer device 19, in particular, the following malfunctions:
i) a lacking or insufficiency of the electromagnetic field generated by said waves,
ii) the presence of only one of said two electromagnetic waves,
iii) a failure of the outer mains power supply.
[0020] Figure 4 shows five electronic circuit assembies which are held within the banknote bunch: an assembly R1 comprising the four batteries 1 which power supply an integrated circuit (the current drain of this integrated circuit will be so small as not to cause any sensible drains of current from the batteries); as the vibration switch 2 energizes the output of said integrated circuit, all of the downstream portions of said circuit will be power supplied; an amplifier unit R2 which amplifies the signals emitted by the antennas 14, 17 of the transmitter means and received by three coils L₁, L₂, L₃ (arranged with their axes perpendicular to one another in order to suitably receive the signal independently from the position of the banknote bunch), said signals being sent to a decoder assembly R3, comprising two decoders DEC1 and DEC2 which are adapted to decode the frequencies of the received signals; said decoder assembly R3 sending signals to a subsequent control logic assembly R4 exclusively if it receives signals having the above mentioned coded frequencies f₁ and f₂; the control logic assembly R4 comprises two stores M1, M2 which respectively store the received signals of frequencies f₁, f₂ (the starting reset RI will reset to its starting condition the control logic); as the adder SO has received both the signals of frequencies f₁, f₂ it will send a logic signal to the assembly G comprising the timer 7 which will count the above mentioned time period t₂ (for example five seconds) selected among several available time periods, and will send a logic signal to an end stage SF controlling the alarm 8 immediately upon expiring of said time period t₂.
[0021] Figure 5 is a diagram of the electromagnetic waves transmitted by the transmitting means, according to a modified embodiment of the device according to the invention; in this embodiment, the two electromagnetic waves, one having a frequency f₁ and the other having the frequency f₂, are irradiated in a overlaying condition through the same area as said second place, and they are not directed to two discrete areas F₁, F₂ as is shown in figure 1. By this embodiment, it is preserved the feature of the device that it is responsive exclusively two given electromagnetic waves having coded frequencies, and that the receiver is supplied under the control of the vibration switch, but there is lost the advantage of controlling the energizing of the alarm depending on the receiving sequence of the two different frequency electromagnetic waves, that is depending on the path followed by the robber. The diagram shows a pulse train of two electromagnetic waves: one having the frequency f₁, the other having the frequency f₂, which are transmitted in a coded manner as follows: during a period of time T₁ there is transmitted the electromagnetic wave having the frequency f₁; during a subsequent period of time T₂ there occurs a rest time in which no signal is transmitted; during a subsequent period of time T₃ there is transmitted the electromagnetic wave having the frequency f₂; during a subsequent period of time T₄ there is another period of rest in which there is no transmitted any signals and so on, the transmitting sequence continuing with the above mentioned sequence of electromagnetic waves having frequencies f₁, f₂ and rest periods.
[0022] Figure 6 shows an electrical diagram in order to perform a self-test of the batteries 1 of the receiver: the assembly GR10 is an operational amplifier with inverter which is used as a comparator; it compares two volatges that is: a fixed voltage provided by a Zener diode and a further voltage which is proportional to the voltage of the batteries 1; if the voltage of the batteries lowers under a preset level, then the output of this assembly will pass to a high logic level; the assembly GR11 provides a set time delay (for example a second) in the detecting of the voltage coming from the assembly GR10; the assembly GR12 is driven by the assembly GR10 and it comprises an oscillator assembly generating a low frequency square wave to be applied to the assembly GR13 comprising a NPN transistor which energizes an acoustical buzzer AA.
a) receiving the first electromagnetic wave as stored in said first state;
b) preserving the storing of said first state with the exit of the field of said first wave;
c) receiving the second electromagnetic wave as stored in said second state;
d) preserving the storing of said second state and actuating fourth counter means (7) counting a second set period of time (t₂) and of:
e₁) actuating said alarm unit (8) as said second period of time (t₂) is expired and, up to the expiring of said second period of time, further performing the steps of:
e₂) receiving said second electromagnetic wave and resetting said fourth counter means (7);
e₃) at the exit from said field of said second electromagnetic wave, receiving the first electromagnetic wave and resetting the storing of the reception of said second electromagnetic wave;
e₄) as said first electromagnetic wave exits said field without receiving said second electromagnetic wave, returning to the state immediately preceding said step a).