DE69906678T2 - Anti-theft display frame - Google Patents

Abstract

A display unit for high value goods comprises a container (10) for visible display and security means for deterring unauthorised removal of the goods, the container itself being relatively weak and unarmoured and in that the security means comprise a plurality of detectors (14, 16, 18, 30) arranged to detect different types of unauthorised actions applied to the container, means (22) for adulterating the goods by applying thereto an adulterating agent when triggered to do so by activation of a detector, and a unit (24) to control the actuation of the adulteration step on input from one or more of the detectors. Preferably the display unit is capable of distinguishing between authorised activity and an attempted theft. <IMAGE>

Description

The invention relates to display racks for use in connection with goods which have a relatively high value but which can be easily damaged, in particular it relates to such a display rack which is protected by a mechanism which detects any unauthorized activity and causes devaluing damage to the goods.

There are many types of goods offered for sale in shops which have a relatively high price but are easy to carry, making them very vulnerable to theft. A particular example is cigarettes and other tobacco products, especially in countries where the level of taxation is very high. Products of this type are generally sold in relatively small packages which are generally wrapped in cardboard or paper containers, generally with an outer clear plastic film, typically made of a cellulose ester.

When goods of this kind are stolen from the racks, the store owner's loss is not only the value of the goods, but the loss includes, to a greater extent, damage to the premises and storage equipment. Conventional solutions to these problems involve secure units of storage racks for use during the store's closing hours. This is inconvenient because the goods must be transferred from the display rack intended for use during the day to a secure overnight storage facility and then returned to the display rack the following day.

An alternative solution to this problem involves the use of highly secured display units themselves. The key idea here is to protect the display unit so that it cannot be broken into by making it of a robust construction, such as a strong steel sheet, and by providing it with secure locking mechanisms. This type of system is very complex and tends to be unsightly or at least unattractive to the consumer. The only other option has been to protect the shop or showrooms by suitable alarm systems, armoured doors, etc. However, these deterrents do not always work and it is unfortunately possible to break into business premises (for example by forcibly entering with a motor vehicle), steal the goods and escape before a guard or the police can arrive.

Security devices for valuable goods such as banknotes, credit cards and documents, in which the goods are defaced or marked with a paint or the like in case of attempted theft, are known in the art. Examples of such security devices have been described in patents US 5,156,272, US 4,722,435, US 3,730,110, GB 1,446,711, GB 1,138,104 and WO 90-09504. However, none of these documents teach the application of such technology to a display case for such goods as described in the present application. Furthermore, the goods can easily be damaged accidentally due to a false alarm.

EP-A-629984 discloses a jewel anti-theft system comprising a removal detection device and an ambient field detection device. In case of attempted theft, the system can release smoke, tear gas, dyes and/or an audible alarm.

It is therefore an object of the present invention to provide a display rack for goods such as cigarettes which is capable of providing a deterrent to unauthorized activity, while remaining attractive to the customer and being available at a lower cost.

It is a further object of the present invention to provide a display device which is capable of distinguishing between authorized activity and attempted theft.

According to the present invention there is provided a display case for high-value goods comprising a container for visible display and a security device for deterring unauthorized removal of the goods, the container itself being relatively weakly built and unarmored and the security device comprising a large number of detectors arranged to detect various types of unauthorized actions performed on the container, a means for tampering with the goods by applying to them a tampering agent when the trigger command to do so is given by activation of a detector, also it comprises a unit for controlling the initiation of the tampering step on the input from one or more detectors, characterized in that a means is able to provide a warning signal in the event of an accidental disturbance (for example cleaning of the display case or its immediate surroundings) in order to avoid further accidental disturbance leading to the initiation of the falsification step.

In particular, the display rack of the invention is intended for use with tobacco products, but it is equally applicable to pharmaceutical products and other high-value goods.

The adulterating agent may take any form known in the art, provided it is capable of sufficiently adulterating the goods so as to render them unsaleable by their obviously stolen appearance. For example, the goods may be adulterated by the application of a dye or a marking agent, by a highly viscous substance which sticks to the goods or by a substance with an unpleasant odour. Preferably, the adulterating agent consists of some form of dye or marking agent, typically a colouring liquid or a powder, which is capable of penetrating the packaging of the goods, for example the outer plastic film and cardboard wrapping of cigarette packets. Any suitable marking agent may be used, provided it has the penetrating ability required for the goods in question. Typically, fluorescent inks may be used, such as those used in other security devices (e.g. containers for banknotes). Preferably, an additive is added to the counterfeiting agent. Such an additive may typically be invisible to the naked eye, but visible to detection means, e.g. an ultraviolet lamp. A typical example is the security ink disclosed in patent SE-B-464 132, although such inks must undergo a minor modification to make them thinner and more penetrant. Such a security ink adheres firmly to the skin and makes it much easier for the police to identify a thief.

The marker does not need to be a complex, expensive chemical: a simple, processable dye, such as caramel or a vegetable dye, can be used, because It is virtually impossible to remove this substance without repackaging the goods once the substance has penetrated the folds and cracks of the cellulose film packaging.

Preferably, the display frame is further equipped with a clear warning device to deter attempted theft.

The display unit may be constructed to have an attractive design and may be made from relatively weak materials. The container for visible display is relatively weak and unarmoured, in other words, if the container is made from such materials and if it is not fitted with a security device, it would not be sufficient to protect the goods from theft. Examples of possible materials include plastic, aluminium, copper and steel. The display unit may be manufactured using any suitable means known in the art, such as by moulding and by extrusion, provided that the display unit so manufactured meets the requirements set out above. The display unit may also be fitted with internally illuminated indicators.

Within the display case, one or more devices for applying the adulterant agent are provided at suitable locations. Such devices may take any form known in the art. Typically, the device for applying the adulterant agent takes the form of a pressurized spray container arranged to be electrically or mechanically activated by the detection system. For example, a pressurized container may be punctured, releasing the adulterant agent contained therein. Alternatively, an aerosol container could be used which is activated by the release of a tensioned spring, as disclosed in US Patent No. 3,730,110. Other possibilities extend to the use of an explosive device, the detonation of which releases the adulterant agent.

In a particularly preferred embodiment, a canister of liquid ink is equipped with a gas generator. When activated, the canister is pressurized and sprays a marking liquid over the goods, thereby discoloring the packaging. Examples of such canisters have been disclosed in the international patent publications WO 83/02975 and WO 92/07159 by Stenild.

The display rack is also equipped with one or more detectors arranged to detect different types of unauthorized activity. Different types of detectors may be used.

In one possible embodiment, the detectors may be arranged to detect tampering, cutting or drilling. Preferably, this may be done by providing a plurality of detectors at different locations on the display case to detect unauthorised activity at different locations thereon. If the display case is closed at the front by a shutter, then the detectors may, for example, be arranged on both halves of the display case, both the top and bottom halves, or alternatively in the respective two halves of the left and right sides. The detectors would detect movement of both halves of the shutter and send an input signal to the control unit to trigger the tampering device.

In another embodiment, the display unit is mounted on the wall and a device may be provided to detect any attempt to remove the display unit from its mounting. Such detectors may consist, for example, of an optical beam detection device, of magnetic contacts or of microswitches.

In another design, the detectors could monitor the removal of goods from the display case (typically a passive IR radiation detection device).

In yet another embodiment, the device may further be suitably provided with a locking mechanism and a detector may detect any attempt to break or otherwise weaken the locking mechanism.

In yet another embodiment, means may be provided to detect the breakage of glass. A plurality of glass layers may be provided, each equipped with a glass break detector capable of providing an input signal to the control unit. Preferably, the glass layers are made of toughened glass. Examples of suitable glass break detectors are those available from Alarmtech AB, Sweden.

In yet another embodiment, means may be provided to detect tampering (in an attempt to deactivate the tampering agent) with an internal circuit contained in the display unit. Typically, where a plurality of devices are arranged to apply the tampering agent, each device is independently connected to the control unit and a current flows through the circuit. Means may be arranged to detect an interruption of this current; in the event this occurs, the control unit will then send an output signal to the remaining devices to apply the tampering agent.

In a preferred embodiment, one or more detectors may be arranged to detect vibrations, such as those caused by drilling, mechanical shock vibrations or explosions. The vibration detectors may be adapted to detect vibrations of different frequency, amplitude and duration. Preferably, a signal from a single vibration sensor may be detected by multiple channels so that vibrations within different ranges of frequency, amplitude and duration [hereinafter referred to as "signature vibrations"] may be detected in a single detector.

It should be noted for clarity that the term "vibration sensor" refers to the actual device for detecting a vibration. Any device capable of generating an electrical signal when displaced by mechanical vibrations can be used as a vibration sensor. Examples of suitable materials include a piezoceramic crystal, a microphone optionally in conjunction with a loudspeaker, a geophone (consisting of a weight moving in a wire coil), a hydrophone, or an array of optical fibers in conjunction with one or more lasers controlled by a Processing device. A piezoceramic crystal is preferred. The term "vibration detector" refers to the entire detector including the sensor and including any processing device/circuit to which the detector is connected.

By "channel" is meant a device for detecting a specific range of the magnitude of frequency, amplitude and duration (detection ranges) so that only such detection ranges are detected and further processed by the detector. The range of detections in terms of the magnitude of frequency and/or amplitude that is capable of being detected by each channel may overlap or it may not overlap.

The frequency, amplitude and duration of detection capable of being demonstrated by each channel may vary depending on the likely means by which theft is attempted and the environmental conditions.

For example, the display rack may be equipped to detect drilling, in which case the channel may be adapted to detect vibrations of relatively high frequency and long duration but small amplitude. Typically, the detection vibration detectable by such a channel is of an amplitude corresponding to an acceleration of 0.001 g to 0.5 g, preferably 0.005 g to 0.1 g, and of a frequency of 1 kHz to 20 kHz, preferably 3 kHz to 10 kHz.

Alternatively, the detector may be capable of detecting mechanical shocks. To do this, the detector may detect vibrations of medium amplitude but of a relatively low frequency and of a short duration. Typically, the detection vibration detectable by such a channel is at a frequency of 0.1 kHz to 10 kHz, preferably 0.3 kHz to 8 kHz, and at an amplitude corresponding to an acceleration in the range between 2 g to 50 g, preferably between 5 g to 20 g.

As a further alternative, the detector may detect more powerful mechanical shock waves, such as those from explosions, in which case the channel may detect vibrations of low frequency and of very high amplitude. Typically, such a detector would detect vibrations of an amplitude corresponding to an acceleration of more than 200 g, preferably more than 600 g, and of a frequency in the range of 0.1 kHz to 10 kHz, preferably 0.3 kHz to 8 kHz.

The vibration detector may further be provided with a device which controls its sensitivity so that the ambient noise can be ignored and will not trigger a tampering step. Typically, the sensitivity of the display rack can be set by testing the rack at various levels of background noise and verifying that such a level is sufficient to trigger the vibration detector.

In a particularly preferred embodiment, the vibration detector may be capable of transmitting at least three different types of signals to the control unit, which signals are described hereinafter as a pulse signal, a warning signal and an alarm signal. The three types of signals may differ from one another by any means known in the art. for example, by voltage, current or duration. For example, a pulse signal can have a duration of less than 30 ms, a warning signal from 30 to 700 ms and an alarm signal of more than 700 ms.

The control unit may be equipped with means to read and distinguish such signals and to trigger the necessary action; such means for such execution will be readily apparent to all those who are experts in the field.

In a particularly preferred embodiment, the vibration detectors may be equipped with a memory; signals entering the detectors may be stored/integrated in the memory. When the signal stored in the memory reaches a pre-programmed value, the vibration detector sends an alarm signal to the control unit to trigger the tampering step. In this way, a continuous low amplitude vibration, such as a drilling vibration or repeated mechanical vibrations, may be detected over a short period of time and the tampering step may be triggered accordingly.

Typically, the signal stored in the memory will decay over time once the vibrations have ceased, so that repeated smaller shock waves or vibrations over a long interval will not trigger the corruption step. In addition, a means may further be provided to reset the signal stored in the memory to zero. The length of time required for the signal to decay will vary depending on the signal detecting the vibrations and the environmental conditions. For example, a signal from the bore detector may take from 10 seconds to 2 minutes, preferably from 20 to 40 seconds, before it decays.

In the event of a more powerful mechanical shock, such as an explosion, the detector, tuned to detect vibrations of such frequency and amplitude, can automatically send an alarm signal to the control unit to trigger the tampering step.

The vibration detector may further be programmed to provide a warning signal to the control unit when the signal stored in the memory has reached a predetermined value, typically a value different from the value required to trigger the corruption step. In response to the receipt of such a signal, the indicator unit issues a warning signal, such as a flash of light or a short beep. In this way, the indicator unit can provide a warning signal prior to triggering the corruption step.

If repeated mechanical shocks are applied to the system within a certain period of time, the detector will provide an alarm signal to the control unit so that the control unit will initiate the tampering step. The display unit can be programmed to change the time, force and number of mechanical shocks required to initiate the tampering step.

In a further embodiment, the device is provided with a means to prevent the tampering step in the event of a fault. Typically, this can be accomplished by means of the control unit detecting a fault in the device and also providing a visible and/or audible warning when the user attempts to arm the device.

For example, if the device is closed by shutters, then the control unit will detect it as a fault when the shutter is pulled down. If there is no fault, then the user is informed by an audible signal and the system is armed. However, if there is a fault, then a different signal is issued and the control unit will not trigger the tampering step. The control unit can typically test for faults several times per second.

The control unit may further be provided with a memory such that every event experienced by the display unit (for example attempted thefts, maintenance, accidental malfunctions, errors) can be recorded. The memory is preferably able to record events for a typical period of time between maintenance work (such as one year). The control unit may further be connected to output devices, such as a screen or a printer, so that a maintenance engineer or the like is easily able to obtain an overview of all events that have taken place.

The display unit may also be equipped with a means of detecting unauthorized intervention in the power supply.

A particular embodiment will now be described with reference to the accompanying drawings in which:

- Fig. 1 is a front view of the display unit in the closed position;

- Fig. 2 is a front view from the inside of the frame;

- Fig. 3 is a side view of the frame;

- Fig. 4 is a schematic representation of the vibration detector in more detail; and

- Fig. 5 is a schematic diagram showing the control unit in more detail.

Referring first to Fig. 1, the frame 10 comprises a generally rectangular frame provided at the front with a roller shutter 12; the roller shutter 12 is provided with a locking mechanism 14 which is coupled to a magnetic control switch and/or to a light sensor. A door sensor 16 is also provided. The frame is provided at the rear with a wall switch 18 (see Fig. 3) which is arranged so that it can be triggered when the frame is removed from its fixed reference position on the wall.

Internally, the rack is provided with a series of rack surfaces 20, each of which is equipped with an associated ink pack to spray ink over the contents of the adjacent rack surface 20 when triggered. A vibration detector 30 is also provided. The various sensors and switches are powered by a power supply included in the control unit 24, which is described in more detail below with reference to Figure 5.

Fig. 4 shows the vibration detector 30 in more detail. A piezoceramic crystal 32 is connected to an amplifier 34, which in turn is connected to a potentiometer 36 and to a bandpass filter 38.

The bandpass filter is further connected to a channel 40 for the detection of drilling, to a channel 42 for the detection of mechanical shocks and to a banal 44 for the detection of explosions, the channels 40, 42, 44 being connected in parallel to each other. The channels 40 and 42 are equipped with a memory. The channels are further connected to a driver 46 which is able to provide an output signal to the LED 48 and to the operating terminal 50 which is able to provide an output signal to the control unit.

The vibration detector will now be described in its use with reference to the following non-limiting example.

The oscillations are received by the crystal 32 and converted into electrical signals, which are amplified by the amplifier 34. The potentiometer 36 ensures that only signals of sufficient amplitude are allowed to pass through the bandpass filter 38 so that environmental noise does not trigger the detectors. The bandpass filter 38 filters out unwanted frequencies so that only those signals that correspond to the oscillations detectable by the detector channels 40, 42, 44 will reach the aforementioned channels. Additional filters can be set up in the channels 40, 42, 44.

In the event of unauthorized access to the display unit by drilling, vibrations that meet the necessary detection criteria (typically 3 kHz to 10 kHz and an amplitude corresponding to an acceleration of 0.005 g to 0.1 g) pass through the bandpass filter 38 and are transmitted to the channel 40. Signals that meet the detection criteria are stored in the memory, which stores a certain number of samples by means of a shift register or the like. Each time an incoming signal is stored, a pulse signal is output from the channel 40. The control unit detects this signal, but it does nothing until a predetermined value is reached.

If the received vibration has continued for a sufficient duration so that the signal in the memory reaches a value specified by the user, then the channel 40 sends an alarm signal to the control unit via the driver 46 and the operator terminal 50. The control unit reads this signal and sends a signal to the tampering device to initiate a tampering step.

Mechanical shock vibrations which meet the "shock" detection criteria (a typical frequency of 0.3 kHz to 8 kHz and an amplitude corresponding to an acceleration of 2 g to 50 g) also pass through the bandpass filter 38 and are transmitted onto channel 42. A signal meeting the shock detection criteria is stored in memory similar to that described above in connection with channel 40 and a warning signal is sent via driver 46 and terminal 50 to the control unit which detects this signal and initiates an audible and/or visual means to provide a warning.

The memory allows to record the time interval between the mechanical shocks. In the case of several shocks in a short period of time, an alarm signal is sent via the driver 46 and the terminal 50 to the control unit, which reads such a signal and triggers the tampering step.

In the event of an explosion, vibrations of very high amplitude (typically corresponding to an acceleration of over 600 g) and of a typical frequency of 0.3 kHz to 8 kHz pass through the bandpass filter 40 and are transmitted to the channel 44. This outputs an alarm signal via the driver 46 and the terminal 50 to the control unit with the aim of triggering the tampering step.

Fig. 5 shows the control unit 24 in more detail. The central control unit 70 is connected to a lock 14, to a door sensor 16 and to a wall sensor 18.

The vibration detector 30 is also connected to the central control unit 70 via a time controller 72 which measures the duration of the signal emitted by the vibration detector 72 and sends an appropriate signal to the central control unit 70.

The central control unit 70 is further connected to the adulteration control unit 74, which is independently connected to the adulterant application devices 76a to 76e. Upon receipt of an alarm signal from the central control unit 70, the adulteration control unit 74 sends a high current signal to any or all of the devices 76a to 76e to apply the agent and adulterate the goods. A low current signal (insufficient to trigger the adulteration device) passes between the unit 74 and the devices 76a and 76e; in the event of unauthorized interference with any of the devices 76a to 76e or their connection to the adulteration control unit 74, the current is interrupted, a high current signal is sent to the other devices for application of the adulterant.

The central control unit 70 is further connected to the power supply control unit 78, which draws electrical energy from the main power supply source 80 and/or from the backup battery 82. In the event of unauthorized interference with the main power supply source 80 or its connection to the power supply control unit 78, a signal can be sent to the central control unit 70, which issues warning and/or alarm signals as the user deems appropriate; until the main power supply is restored, the battery 82 provides the backup voltage.

The unit is further equipped with an output controller 84 which is connected to a buzzer 86 for warning, to an alarm buzzer 88 and to a display unit 90. Also provided is an event log 92 which is able to record any event experienced by the display unit (for example attempted thefts, maintenance, accidental malfunctions or faults). This event log can further be connected to an event printer 94 so that the maintenance engineer or the like will easily be able to obtain an overview of all events which have taken place.

Claims (16)

1. A display unit (10) for goods of high value, comprising as elements; a container for visible display and a security device for deterring unauthorized removal of the goods, the container itself being relatively weakly constructed and unarmored, the security device comprising a large number of detectors (14, 16, 18, 30) arranged to detect various types of unauthorized actions performed on the container; means (22) for tampering with the goods by applying a tampering agent to them when triggered to do so by the activation of a detector, and a unit (24) for controlling the actuation of the tampering step as a result of the input from one or more detectors, characterized by means capable of providing a warning signal in the event of accidental disturbance. 2. Display frame according to claim 1, which is equipped with a means (30) for detecting a vibration. 3. Display rack according to claim 2, wherein the vibration detector (30) is adapted to detect vibrations of different amplitude, frequency and duration. 4. A display rack according to claim 3, wherein a signal from a single vibration sensor (32) can be detected through multiple channels (40, 42, 44) so that vibrations within different ranges of frequency, amplitude and duration can be detected by a single vibration detector. 5. Display rack according to any one of claims 2 to 4, wherein the vibration detector (30) is equipped with a memory. 6. Display rack according to any one of claims 2 to 5, wherein the vibration detector (30) is capable of supplying at least a pulse signal, a warning signal and an alarm signal to the control unit. 7. Display unit according to claim 6, wherein the vibration detector (30) provides an alarm signal when the signal in the memory reaches a preset value. 8. Display unit according to claim 7, wherein the vibration detector (30) provides a warning signal when the signal in the memory reaches a preset value. 9. Display unit according to any one of the preceding claims, provided with a large number of glass layers, each layer being provided with a glass breakage detector capable of providing an input signal to the control unit. 10. A display rack according to any preceding claim, wherein the detectors (14, 16, 18, 30) are positioned at different locations thereon to detect unauthorized access at different locations. 11. A display unit according to any preceding claim, in which the adulterant is a liquid or powder which causes a marking or a colouring. 12. A display according to claim 11, in which an additive is added to the adulterant, which additive is invisible to the naked eye but visible to scanning means. 13. Display unit according to any one of the preceding claims, in which the means (22) for tampering with the goods comprises a canister of liquid ink coupled to one or more gas generators. 14. A display unit according to any preceding claim, further comprising a means for informing the user and preventing the tampering step in the event of an error being made when the user attempts to arm the unit. 15. A display unit according to any preceding claim, equipped with means for detecting tampering by means of an internal circuit contained therein. 16. A display unit according to any preceding claim, in which the high value goods are tobacco products.