EP2304142B1 - Anti-theft system including a magnetic-field-sensitive element - Google Patents

Abstract

The invention relates to an anti-theft system for protecting an item, including: - a protection element (1), associated with the item to be protected, which can move between a position in which the item is locked and a position in which the item is released; means (11) for magnetically locking the protection element (1) in the protection position thereof, which means can be deactivated using a magnetic lock opener; an alarm; alarm activation and deactivation means (20, 28); and a magnetic-field-sensitive element (30) configured to trigger the alarm when said sensitive element (30) is subjected to a magnetic field.

Description

The invention relates to an anti-theft system for the protection of an article.

The invention relates more particularly to antitheft systems comprising a housing, and a safety device comprising magnetic locking means of the opening of the housing, which can be deactivated with the aid of a specific magnetic unlocker.

STATE OF THE ART

In order to prevent the theft of commercial products, it is known to dispose the products to be protected in a housing provided with a detection means, able to interact with the security gates placed at the exit of a self-service space . Thus, during the passage of an article protected by such a housing in front of a gantry detection, the detection means triggers an alarm, arranged in a security gantry. Such a device, corresponding to the preamble of claim 1, is for example known from the US 2007/0159327 A1 .

In order to limit the risk of fraudulent extraction of the article, the antitheft devices are equipped with a magnetic locking system, which can be deactivated by means of a specific magnetic unlocker.

However, malicious people may try to disable the magnetic locking system by placing one or more magnets close to it. After many attempts, it can not be excluded that these people manage to disable the magnetic locking system by approaching one or more permanent magnets, judiciously arranged, near the locking system. Thus, the fraudsters then cause inhibition of the locking system and could extract the article of the anti-theft housing.

OBJECT OF THE INVENTION

The invention aims to remedy this problem by proposing an anti-theft system comprising a housing and magnetic locking means of the opening of the housing, to prevent malicious disabling of said locking means.

• un élément de protection associé à l'article à protéger mobile entre une position de protection et une position de libération de l'article ;
• des moyens de verrouillage magnétique de l'élément de protection dans sa position de protection, désactivables à l'aide d'un déverrouilleur magnétique,
• une alarme ;
• des moyens d'activation et de désactivation de l'alarme;
• un élément sensible aux champs magnétiques agencé pour déclencher l'alarme lorsque ledit élément sensible est soumis à un champ magnétique.

For this purpose, the invention proposes an antitheft system for the protection of an article comprising:

• a protection element associated with the movable article to be protected between a protection position and a release position of the article;
• magnetic locking means of the protection element in its protective position, deactivatable by means of a magnetic unlocker,
• an alarm ;
• means for activating and deactivating the alarm;
• a magnetic field sensitive element arranged to trigger the alarm when said sensing element is subjected to a magnetic field.

Thus, when a magnet is approached by the locking means, an alarm is triggered so as to warn the supervisory agents and / or the personnel of the sales area that an attempt is made to deactivate the locking means.

Advantageously, the anti-theft system comprises an alarm circuit comprising a delay for delaying the triggering of the alarm by said sensitive element by a predetermined duration, the means for deactivating the alarm inhibiting the alarm when said alarm has been activated. been deactivated during the specified period.

Thus, thanks to this delay, the alarm is triggered only when it has not been deactivated for the duration of the time delay. Untimely tripping of the alarm is therefore limited. Indeed, in normal use, when using a suitable unlocker to disable the locking means, the locking means and the alarm are normally deactivated by the unlocker during the delay period. There is therefore no alarm trigger inappropriate. On the contrary, during an attempted fraud, the fraudster will not have enough time, from its first attempt to disable the locking means, to disable the alarm. In this case, the alarm will be triggered.

For these reasons, it is clear that the delay time must be long enough to allow the alarm to be deactivated under normal conditions of use but, in return, limited to prevent the fraud attempt as soon as possible. Thus, the delay time is of the order of a few seconds.

Advantageously, the magnetic field sensitive element is a flexible blade switch (ILS) and is disposed near the magnetic locking means, so that when the locking means are subjected to a magnetic field sufficient to unlock them, the Magnetic field sensitive element triggers the alarm.

In a preferred embodiment, the protection element is a housing.

Advantageously, the safety device comprises a contactor comprising a probe cooperating with a portion of the housing when the latter is closed, said contactor being arranged to trigger the alarm when the probe no longer cooperates with said portion of the housing. Thus, the system according to the invention is also able to detect a forced opening of the housing.

Advantageously, the anti-theft system comprises a safety device comprising the magnetic locking means, the alarm, the means for activating and deactivating the alarm, the element sensitive to magnetic fields and a housing housing of the components. said security device.

According to a preferred embodiment, the security device comprises an omnidirectional detection means housed in said envelope. Advantageously, the omnidirectional detection means is an RF or AM ferrite. Thus, the antitheft system is more difficult to neutralize.

In one embodiment, the safety device comprises an alert means comprising a coil buzzer whose longitudinal axis of said coil is oriented parallel to the widest width of the housing, the coil being furthermore placed at a distance from the faces side of the case. The aim is to prevent the application of an external magnetic field from disturbing the operation of the buzzer.

Advantageously, the security system comprises a locking latch, movable in translation, acting on the locking means of the opening of the housing and an activation tab of the alarm, movable in translation, independently of the first pull. This structure makes it possible to separately control the locking and the activation of the alarm.

In one embodiment, the security system further comprises alert means including means for communicating an alarm signal to a remote device. Thus, an alarm signal can be directly transmitted to the monitoring station in order to try to intercept the fraudster as soon as possible.

BRIEF DESCRIPTION OF THE FIGURES

• la figure 1 est une vue en perspective d'un dispositif anti-vol selon l'invention ;
• la figure 2 est une vue latérale en perspective du dispositif de sécurité selon l'invention ;
• la figure 3 est une vue latérale en perspective du dispositif de sécurité représentant le côté latéral du dispositif, opposé au côté représenté sur la figure 2 ;
• la figure 4 est une vue schématique de dessous du circuit d'alarme équipant le dispositif ; et
• la figure 5 est une vue schématique latérale du circuit d'alarme de la figure 4.

Other objects and advantages of the invention will become apparent from the following description, made with reference to the accompanying drawings, in which

• the figure 1 is a perspective view of an anti-theft device according to the invention;
• the figure 2 is a perspective side view of the security device according to the invention;
• the figure 3 is a perspective side view of the safety device representing the lateral side of the device, opposite the side shown on the figure 2 ;
• the figure 4 is a schematic bottom view of the alarm circuit fitted to the device; and
• the figure 5 is a schematic side view of the alarm circuit of the figure 4 .

EXAMPLE OF REALIZATION

The invention, represented on the figure 1 , comprises a protective element comprising two shells 2, 3 transparent plastic, forming a housing 1 for receiving the article to be protected. The two shells 2, 3 are connected to each other by a hinge 4 allowing the opening and closing of the housing 1 to introduce or extract the article. In the embodiment shown, the casing is of parallelepipedal shape and each shell comprises a large face 5 and four small lateral faces 6, 7, 8 and 9.

In order to maintain the housing 1 in the closed position, the device is equipped with a safety device 10, shown in detail on the Figures 2 and 3 , comprising magnetic locking means 11. For this purpose, one of the shells 3 has, on the opposite side 8 to the hinge, a slot 12 for receiving said safety device 10. The safety device 10 can be engaged in the light 12 of the shell 3, from the inside, when the housing 1 is open.

The safety device 10 comprises a plastic casing 13 for accommodating the various elements of the device 10. Preferably, the plastic casing 13 is made of opaque plastic in order to conceal the structure of the locking means 11. The upper part 14 of the device 10 is housed inside the housing 1 and comprises an alarm circuit 16. The lower part 15 emerges from the housing 1 and comprises the locking means magnetic 11, also called locking trigger. The upper portion 14 has a section greater than the section of the lower portion 15, emerging.

The lower part 15 of the safety device 10 has lateral openings 17, 18, represented on the figure 3 , for the passage of claws, not shown, provided on the other shell 2. When the housing 1 is closed, the claws are introduced into the side openings 17, 18 and interact with a locking pull 19 to lock the opening the housing 1. When the housing 1 is closed, the safety device 10 can no longer be removed and the housing 1 can no longer be opened. One or more weights 21, 22, 23 lock the locking tab 19 in the locked position.

In addition, in the illustrated embodiment, the security device also includes an activation zipper 20 of the alarm. Similarly, one or more weights 21, 22, 23 ensure the locking of the activating tab of the alarm 20 in the activated position.

The drawbars 19, 20 are associated with springs which push them, respectively in the unlocking position and disarming the alarm. When the specific unlocker cooperates with the lower part 15 of the device 10, permanent magnets of the unlocker, provided in a particular provision; interact magnetically with the flyweights 21, 22, 23 and the drawbars 19, 20 are released and pushed to the unlocking position and deactivation by the springs. Thus, the alarm is deactivated and the housing 1 can be opened.

The magnetic locking means used may in particular be of the type described in the document FR 2,812,746 . The locking mechanism comprises at least two locking points, such as flyweights, and preferably comprises at least three independent locking points.

Note also that the use of flyweight (s) 21, 22, 23 to secure the drawbars 19, 20 is a known solution, which could be replaced by other locking means such as a flexible blade.

It is also noted that the safety device 10 according to the invention can be adapted to housings 1 of different shapes and sizes. This embodiment therefore makes it possible to offer a complete range of housings 1 all using the same "safety device".

Advantageously, the lower part 15 of the envelope 13 of the safety device 10 comprises a symbol, such as a not shown arrow, indicating to the operators the unlocking direction of the magnetic locking system 11. This symbol makes it easier to understand the manipulations to be performed to disable the locking system 11. Thus, in the context of the present invention, this symbol reduces the inappropriate triggering of the alarm due to handling too long exceeding the duration of the delay.

The figure 4 represents the alarm circuit 16 which is housed in the upper part 14 of the safety device 10.

The alarm circuit 16 comprises a microcontroller, not shown, for managing the functions of the alarm circuit, an electrical generator, such as a battery 24 and an electronic card 25 for supporting the components.

The circuit 16 includes an alert means for notifying an attempted theft and put into operation, when the alarm is triggered. In the embodiment shown, the warning means is composed of a buzzer 26 producing an audible signal when a voltage is applied thereto. In the detailed embodiment, the buzzer 26 comprises a membrane and a coil 27 exciting the membrane. This solution is inexpensive. However, the coil 27 of the buzzer 26 is sensitive to magnetic fields. Thus, by bringing a magnet close to the coil 27 of the buzzer 26, it is possible to disturb the buzzer 26 and thus to drop the intensity of the sound emitted by it. In order to limit this disadvantage, the longitudinal axis a1 of the coil 26 is oriented parallel to the largest width of the housing 1 (length of the face 8) and the coil 26 is placed in a central position, away from the lateral faces 7, 9 of the housing 1.

In another embodiment not shown, the buzzer 27 uses a technology without excitation coil, more expensive, and is therefore not sensitive to magnetic fields.

According to other embodiments, it is also possible for the alarm circuit to include other warning means. For example, the warning means may further comprise means for communicating an alarm signal to a remote device. Thus, the device according to the invention makes it possible to inform a security station of an attempted theft and, preferably, of the position of the case in question in the sales area. These communication means may in particular be radiofrequency transmitters and may be activated simultaneously with the audible alarm 26.

The alarm circuit 16 also includes an activation switch 28 of the alarm circuit 16. The switch 28 comprises a movable lever 29 cooperating with the activation pull tab 20. Thus, when the pull tab 20 is locked in the activated position the alarm circuit 16 is energized (activated) and when the pull tab 20 is in the deactivated position, the alarm circuit 16 is not powered.

As previously indicated, the security device includes an alarm activation tab 20 and an independent locking tab 19. Thus, the locking means 11 can be locked without the alarm being triggered. Therefore, in certain circumstances, when the housing 1 is kept in stock, for example, the autonomy of the alarm circuit can be reserved. In addition, this configuration can also be advantageous when one wants to avoid the inconvenience of a strident ringing in case of unexpected handling.

According to the invention, the alarm circuit 16 also comprises a magnetic field sensitive element 30, disposed near the magnetic locking means 11. Preferably, this pressure-sensitive element is a flexible blade switch or ILS, establishing or cutting an electrical connection depending on the presence or absence of a magnetic field. In the presence of a magnetic field, the magnetizable contacts magnetize by influence, and are attracted to each other. Thus, the contacts come closer and touch each other, establishing the current. When the magnetic field ceases, the magnetization also ceases, and the elasticity of the contacts spreads them, thus cutting off the current.

The I.L.S. 30 is connected to the microcontroller which detects a change of state of I.L.S.30. The microcontroller comprises means for delaying the triggering of the alert means (s). The delay time is, for example, between 3 to 10 seconds, and preferably of the order of 4 to 5 seconds.

Thus, as soon as a magnet is approached near the ILS, the contacts of the ILS meet and, when the delay time expires without the alarm has been disabled, the microcontroller feeds the buzzer 26 which then emits a warning sound.

The ILS 30 is positioned near the weights 21, 22, 23 of the locking means 11 and has an adequate sensitivity so that, when the locking means 11 are subjected to a magnetic field sufficient to deactivate them, the flexible blades of switch 30 meet.

In the illustrated embodiment, the surfaces of the blades of the ILS 30 are oriented parallel to the length of the trigger and the location of the unlocker in the disabling position of the locking means. Thus, when approaching a magnet in the unlocking direction of a flyweight, the blades connect.

Furthermore, the alarm circuit 16 also comprises a contactor 31 comprising a probe 32 cooperating with a portion of the housing 1 when the latter is closed. When the probe 32 no longer cooperates with said part of the housing 1, the contactor triggers the alarm and the buzzer 26 is powered.

For this purpose, the envelope 13 of the safety device has a longitudinal slot 33 for engaging the edge of the opposite shell 2. At the bottom of this slot 33 is housed the contactor 31 whose probe 32 is flush with the surface of the bottom of the slot 33. This contactor interacts with a central zone of the edge of the complementary shell 2. The centering makes it possible to obtain the most effective effect for triggering in the event of forced opening. When the two shells 2, 3 are assembled, the switch 31 is activated and controls the shutdown of the alarm. On the other hand, when the edge stops pressing the contactor 31, the contactor is released and triggers the alarm. This situation occurs when one tries to separate the two parts of the shell 2, 3, especially in the event of destruction of the locking system 11 or in case of forcing of the latter.

In a preferred embodiment, the device comprises a light-emitting diode 34 which is powered when the alarm circuit 16 is energized and energized. This diode 34 has the function of indicating whether the alarm is activated and can also deter dishonest consumers by revealing that the housing 1 is equipped with an alarm.

The housing 1 is further provided with a detection means 35, detectable by gantries arranged at the outputs of the sales area. The detection means 35 may in particular be an RF tag, circuit or coil, a RFID tag, circuit or coil, an RF ferrite, an electromagnetic tag or a magnetoacoustic tag or ferrite.

Preferably, the detection means 35 is of the omnidirectional type and is housed in the envelope 13 of the safety device. Indeed, the casing 13 of the safety device 10 makes it possible to provide a housing having a sufficient volume to house means allowing the detection of omnidirectional, a ferrite having a cylindrical shape for example. In a preferred embodiment, the detection means is an RF or magnetoacoustic (AM) ferrite.

The invention is described in the foregoing by way of example. It is understood that the skilled person is able to realize different embodiments of the invention without departing from the scope of the invention, as defined by the appended rependications.

Claims (14)

1. Anti-theft system for protecting an item comprising:

   - a protection element (1) associated with the item to be protected, movable between a protection position and a position for releasing the item;

   - magnetic locking means (11) for locking the protection element (1) magnetically in the protection position thereof, suitable for deactivation using a magnetic unlocking element,

   - an alarm;

   - means for activating and deactivating the alarm (20, 28),

   characterised in that it comprises a magnetic-field-sensitive element (30) arranged to trigger the alarm when said sensitive element (30) is subjected to a magnetic field.
2. Anti-theft system according to claim 1, characterised in that it comprises an alarm circuit (16) comprising a time delay to offset, by a predetermined time, the triggering of the alarm by said sensitive element (30), the means for deactivating the alarm inhibiting the alarm if said alarm has been deactivated for the predetermined time.
3. Anti-theft system according to claim 1 or 2, wherein the magnetic-field-sensitive element (30) is a reed switch (ILS).
4. Anti-theft system according to claim 3, characterised in that the surfaces of the reeds of the reed switch (30) are perpendicular to the direction for deactivating the locking means.
5. Anti-theft system according to any of claims 1 to 4, characterised in that the magnetic-field-sensitive element (30) is arranged in the vicinity of the magnetic locking means (11).
6. Anti-theft system according to claim 5, characterised in that the sensitive element (30) is positioned with respect to the magnetic locking means (11) and arranged such that, when the locking means (11) are subjected to a sufficient magnetic field to deactivate same, the magnetic-field-sensitive element (11) triggers the alarm.
7. Anti-theft system according to any of claims 1 to 6, characterised in that the protection element (1) is a housing.
8. Anti-theft system according to claim 7, characterised in that it comprises a contactor (31) including a sensor (32) engaging with a portion of the housing (1) when said housing is closed, said contactor (32) being arranged to activate the alarm when the sensor (32) no longer engages with said portion of the housing (1).
9. Anti-theft system according to any of claims 1 to 8, characterised in that it comprises a safety device (10) comprising the magnetic locking means (11), the alarm, the means for activating and deactivating the alarm (20, 28), the magnetic-field-sensitive element and a casing (13) for housing the components of said device (10).
10. Anti-theft system according to claim 9, characterised in that the safety device (10) comprises omni-directional detection means (35) housed in said casing (13).
11. Anti-theft system according to claim 10, characterised in that the omni-directional detection means (35) is an RF or AM ferrite.
12. Anti-theft system according to any of claims 1 to 11, characterised in that the safety device comprises a warning means comprising a buzzer (26) with a coil (27) wherein the longitudinal axis of said coil (27) is oriented parallel with the widest dimension of the housing (1), the coil (27) being further positioned at a distance from the side faces (7, 9) of the housing (1).
13. Anti-theft system according to any of claims 1 to 12, characterised in that the safety system (10) comprises a translatable locking pull (19), actuating the locking means (11) for opening the housing and a translatable alarm activation pull (20), separate from the first pull.
14. Anti-theft system according to any of claims 1 to 13, characterised in that the safety system (10) further comprises warning means comprising means for communicating an alarm signal to a remote device.

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