EP0893562A1 - Device for protecting objects against theft - Google Patents

Abstract

The locking device has a flexible cord with its first end (4) firmly clamped in a generally triangular support element. The cord consists of a central wire inside a flexible tube, made e.g. of nylon and there is a spiral spring (3) which is wrapped around the outer diameter of the nylon tube. A tubular rubber sheath (17) surrounds the spring near the first end of the cord. This end of the cord is bent into a circle. The cord, without the rubber sheath, passes in a straight line through a passage in the support element. It may be locked in place by a spring-loaded (10) piston (9) which engages between two adjacent coils of the spring. The second end of the cord is fixed in a pull handle (14). Ultrasonic or electromagnetic sensors may be provided which detect any disturbance to the wire.

Description

The invention relates to a device for protection of objects against theft, in particular a device capable of being detected remotely during crossing of a detection device.

This detection device is generally located on a compulsory passage, for example at the exit of cash registers in a store, and comes under the shape of a gantry so as to be able to detect the theft of a protected object and, in this case, trigger a alarm. Generally, we take advantage of this checkout to neutralize the protective device so as to avoid triggering an alarm.

• selon un premier principe, désigné par la suite "détection radiofréquence", l'appareil de détection émet un signal avec une certaine fréquence et le dispositif de protection est généralement constitué par un circuit résonnant que l'on peut trouver sous la forme d'une pastille adhésive, comportant une bobine en forme de spirale. Le circuit entre alors en résonance sous l'influence du signal de détection et cette résonance constitue la perturbation.
• selon un second principe, désigné par la suite "détection électromagnétique", l'appareil de protection génère un champ magnétique, par exemple par l'intermédiaire d'une bobine de champ, et le dispositif de protection comporte un élément détectable, tel qu'un fil ou un ruban, qui possède certaines propriétés magnétiques ou physiques susceptibles de déformer le champ magnétique généré par l'appareil de protection. Cette déformation de champ constitue la perturbation

Conventionally, the protected object causes a disturbance in the operation of the detection device. This disturbance is then detected so as to trigger an alarm. Two detection principles can be used:

• according to a first principle, hereinafter referred to as "radio frequency detection", the detection device emits a signal with a certain frequency and the protection device is generally constituted by a resonant circuit which can be found in the form of a adhesive patch, comprising a coil in the form of a spiral. The circuit then enters into resonance under the influence of the detection signal and this resonance constitutes the disturbance.
• according to a second principle, hereinafter referred to as "electromagnetic detection", the protection device generates a magnetic field, for example by means of a field coil, and the protection device comprises a detectable element, such as a wire or ribbon, which has certain magnetic or physical properties which can distort the magnetic field generated by the protective device. This field distortion constitutes the disturbance

There is also known a device for protecting round, square or rectangular shape, which we will designate thereafter "plate", which is fixed on the object to protect by means of connection.

We already know, from document FR-A-2 611 128, a anti-theft device for the protection of objects presenting a hanging structure, such as a bottle or a bottle, and using such a blister. The device of protection comprises connection means comprising locking means for locking the wafer and connection means for fixing the connection means on the hanging structure.

The locking means are constituted by a button to lock the plate and the means of connection are constituted by an adjustable collar of which one end is fixed to the connection means and the other free end passes through the connection means, at through a light, so as to form a collar. The collar has a threaded structure on the surface. A flexible blade cooperates at one end with the button and by a second end with a piston which immobilizes the collar.

In operation, the collar is tightened around the object to be protected by pulling the free end. As soon as the collar is in place, the plate is locked by exerting an effort on the button. By this effort, we also deforms the first end of the blade flexible which acts, by its second end and at the like a lever, on the piston which has an edge acute fitting between two neighboring turns of the thread of the necklace. To release the device from the object protected, remove the button using a tool suitable and a spring, located in the piston, exerts a force on said piston so as to release the collar.

A particular drawback of this device is that the plate allows to have an external socket, made of important external dimensions, which allows to exert a traction effort so as to disconnect the wafer from its connection means and, thus damaging the protective device rhedibitory way for good protection of the object. Thus, the means of connection must be sized to withstand such efforts, this which increases the overall size and the cost of such protective devices.

The object of the invention is to propose a new theft protection device that can in particular make it possible to solve the problems mentioned above, which can be very compact and present a high resistance of the connection between the device and the object.

With these objectives in view, the object of the invention is a device for protecting objects against theft, suitable for being detected remotely when crossing a detection device, comprising a means of attachment flexible likely to cross or enclose objects to be protected, tensile and shear resistant as well as a detectable element, characterized in that the attachment means comprises a sheath of material substantially non-magnetic and the detectable element is a wire detectable by detection devices using an electromagnetic detection principle, extending to inside the sheath.

The invention allows, by comparison with the technique to propose a protective device for simple design since it has a detectable wire extending inside the sheath. This device is detectable by functioning detection devices according to the principle of electromagnetic detection. Thread detectable eliminates the use of insert, which considerably reduces the dimensions of the device, without reducing the mechanical resistance required. In addition, the sheath, with high tensile strength and shear, effectively protects the wire detectable, difficult to access from the outside, against any attack aimed at damaging the device. Thus, the device allows effective protection of anti-theft items. The use of a material sheath non-magnetic or weakly magnetic avoids any magnetic interference with the wire detectable and thus ensure detection within best conditions.

Preferably, the sheath has a layer notched device, the notches of which ensure locking the flexible attachment means so functionally equivalent to the threaded structure described in document FR-A-2 611 128 already cited.

This notched layer is preferably made of a metallic wire shaped in a spiral, having the shape of a spring, but without being significantly deformable in traction. However, this layout provides significant flexibility attachment means allowing the adaptation of the device to any form of object, for example the neck a bottle or flask or any other object on which the protective device can be placed. The device can thus enclose the object as closely as possible, minimizing the play between the means of attachment and the object, which would otherwise facilitate the introduction of a tool allowing the removal of the device. So you can't easily release the object device without making use of a means of adequate unlocking, as will be seen later.

According to a preferred embodiment, the means of attachment is secured by a first end to a housing having a channel in which slides, according to a tightening direction, free part of the means attachment, distant from the first end, the housing further comprising a locking means unlockable cooperating with the free part of the means of attachment.

In this way, the attachment means has a shape in collar, adjustable opening, particularly suitable to be placed and tightened around the neck of a bottle, flask or any other object allowing to attach the device. Once the device is placed on the object, the blocking means prevent the sliding of the free part in the channel, in the opposite to the tightening direction.

Preferably, the blocking means is consisting of a piston comprising a piston head cooperating with notches of the notched layer under the action of a return spring and the piston head is of substantially non-magnetic material, so as to avoid any harmful interference with the detectable element.

The piston is slidably mounted in a bore in a direction transverse to the channel, and pushed towards the channel by the return spring. The piston head is provided with an edge which engages in the channel and which is shaped so that it can engage between the notches of the notched layer. The piston works like a ratchet to allow the attachment means to slide in one direction, according to the tightening direction, and prevent sliding in the other direction.

The device is unlocked by moving the piston, against the force exerted by the return spring, to release its edge from the notches of the attachment means. For this, preferably, the body of the piston is made of a magnetic material of so that it can be moved by a device magnetic unlocking, of a type known per se.

Also preferably, the sheath has a sleeve, of material which is deformable in bending but little deformable in compression, substantially non-magnetic located between the notched layer and the detectable wire. According to a example of embodiment, the sleeve is a cable and the wire detectable is placed in the cable.

Sleeve protects detectable wire and prevents this to come into contact with the notched layer. Of plus, it also contributes to tensile strength of the attachment means.

According to a preferred embodiment of the invention, the attachment means comprises a wire reinforcement placed inside the sheath and extending substantially parallel to the detectable wire.

The reinforcing wire also participates in the tensile strength of the attachment means. Moreover, when the notched layer is in the form of a spring, the constituent wire of the spring grips the sleeve so as to ensure between the wire and the sleeve a link which also helps prevent the spreading of turns during a tensile force exerted on the medium of attachment. Thus, the reinforcing wire then also serves avoid radial crushing of the sleeve, ensuring thus the said connection between the sleeve and the wire of the spring.

Preferably again, the case is made in two parts which are symmetrical with respect to a separation plane corresponding to the joint plane of the case which can be advantageously produced by molding and then assembled using glue or ultrasonic welding.

Other features and benefits of the invention will appear in the description which goes theft protection according to the invention.

• la figure 1 est une vue en coupe du moyen d'attache montrant le ressort, le manchon et le fil détectable,
• la figure 2 est une vue de face montrant le dispositif de protection, une des deux parties constituant le boitier étant préalablement enlevée,
• la figure 3 est une vue de face du détail A de la figure 2 montrant la tête de piston s'engageant entre les spires du ressort pour immobiliser le moyen d'attache,
• la figure 4 est une vue de face montrant une des deux parties constituant le boitier,
• la figure 5 est une vue en perspective montrant le boitier,
• la figure 6 est une vue en coupe transversale d'une variante de réalisation du moyen d'attache, pourvu d'un fil de renfort,
• la figure 7 est une vue en coupe d'une variante de réalisation du manchon.

Reference is made to the appended drawings in which:

• FIG. 1 is a sectional view of the attachment means showing the spring, the sleeve and the detectable wire,
• FIG. 2 is a front view showing the protection device, one of the two parts constituting the case being removed beforehand,
• FIG. 3 is a front view of the detail A of FIG. 2 showing the piston head engaging between the turns of the spring to immobilize the attachment means,
• FIG. 4 is a front view showing one of the two parts constituting the case,
• FIG. 5 is a perspective view showing the case,
• FIG. 6 is a cross-sectional view of an alternative embodiment of the attachment means, provided with a reinforcing wire,
• Figure 7 is a sectional view of an alternative embodiment of the sleeve.

The attachment means, shown in Figure 1 and designated thereafter "link", comprises a detectable wire 2, of cylindrical or flattened section, which extends inside a sheath 1 consisting of a sleeve 11 and a layer notched device 3 constituted by a winding in spiral of a metal wire around the sleeve 11, in spring form.

This notched layer will be designated later "spring", although it is not intended to accept axial deformations, but only at allow flexibility of the link.

Detectable wire 2 can be detected remotely by a detector (not shown) using detection electromagnetic. A detectable wire of this type is described in document FR-A-2573895, but the device protection is not limited to the use of this wire.

For practical manufacturing reasons, the wire detectable 2 extends over the entire length of the link, this which makes it possible to fabricate the link in great length, and then cut it to the desired length. The detectable wire 2 could however be shorter than the sheath, without do not interfere with detection.

The sleeve 11, made of a relatively material rigid, but able to deform in bending, as by example a plastic material such as Nylon (brand deposited), wraps the detectable wire 2.

As shown schematically in Figure 7, the sleeve can also be made in the form of a cable 11, i.e. an assembly of strands metallic 110 which are in a non-magnetic material and which are twisted, in which we place the wire detectable 2. The detectable wire extends near the central strand forming the core of the cable. It is to highlight that the cable 11 of Figure 7 is shown only as example. In particular, we can use a cable, of a different design, which may include more or fewer than 110 twisted strands. We can also use detectable wire 2 as strand 110 or, depending on another embodiment, the strands 110 may consist of an assembly of twisted wires (not shown) and the detectable wire 2 could be one of constituent wires of the strand. Spring 3 has a pitch of low p turns, only slightly higher than diameter of the wire which constitutes it, which allows protect the detectable wire 2 against any attack outside. In addition, the spring 3 is produced in a material with mechanical characteristics high, much higher than those of the sleeve 11, of so as to withstand significant constraints of tensile and shear forces exerted on the link.

For example, the spring 3 has the following characteristics: an outside diameter of 3.2 mm, a wire diameter of 0.8 mm, a pitch of 1.3 mm and a shear strength of the order of 1400 N / mm ² .

Spring 3 is made of metallic material non-magnetic, for example a bronze-beryllium alloy, to avoid any original interference electromagnetic with detectable wire 2, so that offer detection in good conditions.

According to the variant shown in the figure 6, the sleeve 11 includes a reinforcing wire 20 which extends substantially parallel to the detectable wire 2 which is in the form of a flat ribbon. The presence of the reinforcement wire 21 in the immediate vicinity of the wire detectable 2 is given only as an example. This arrangement makes it possible to stiffen the sleeve 11 while avoiding its crushing under the radial pressure exerted by the spring 3, as explained above.

The protection device, shown in Figure 2, includes the link, like the one described above, as well as a box 5. The link, shaped in a loop, is fixed by a first end 4 to the housing 5 and a free part 7, distant from the first end 4, slides in a channel 6 made in the case and in which link can be locked.

The case 5 has an edge, in contact with the object to protect, shaped into a curve to substantially match the shape of the object, so as to ensure a certain continuity of the loop form of the link even for different dimensions of this loop, allowing to obtain the closest possible contact between the device and the object on which it is placed.

The first end part 4 of the link comprises a protuberance 12, produced by an increase in the outer diameter of spring 3, locked in a housing 13 made in the housing 5.

The second end 14 of the link is provided with a zipper 15, which can be removable and which allows to exert a traction effort necessary for the link encloses the object to be protected. In addition, to prevent spring 3 cannot scratch the object to be protected, the link comprises a sheath 17, located on the periphery of the link and made of a flexible material such as rubber, which extends between the first end portion 14 and the movable part 7 of the link.

As shown in Figure 3, locking the link in channel 6 is provided by a piston 8 mounted sliding in a bore 19 made in the housing 5 and extending in a direction transverse to the tightening direction. A head 9 of the piston 8 has a edge which is inserted between two turns of the spring 3, located on the free part 7 inside the channel 6, under the action of a return spring 10 acting on the piston 8.

When the link is pulled by the pull tab 15, the free part 7 of the link can slide freely at inside the channel 6 because each turn of the spring 3 exerts a force on the piston 8 so as to push back the return spring 10.

However, when you exert an effort on the link to loosen the loop, i.e. an effort opposite to the tightening direction of the link around the object, the turns of the spring 3 then exert a force on the edge of the steering piston head 9 perpendicular to the sliding direction of the piston.

The piston 8 comprises a body 16, made of material metallic magnetic so as to unlock the protective device, acting from the outside to using a magnet, to move the piston 8 to against the action of the return spring 10. For make the piston 8 comprising a non-magnetic head 9 and a magnetic body 16, the piston head 9 is fitted, with a tight fit, on the body 16 of the piston.

The reinforcing wire 21 is also produced in a substantially non-magnetic material to avoid interference with the detectable wire 2.

As shown in Figures 4 and 5, the housing 5 comprises two parts 5a, 5b symmetrical with respect to a separation plan located between the two parties. As the separation plane corresponds to the joint plane of the housing 5, the case could advantageously be produced by molding. Preferably, the box 5 will be produced in a moldable plastic material having a large mechanical resistance, such as PVC or ABS.

This arrangement makes it easier to assemble the piston 8, return spring 10 and sheath 1 constituting the protective device inside of part 5a of box 5 and then we place the other part 5b in correspondence with part 5a. As soon as the assembly is complete, the two parts 5a are joined together, 5b of the case 5 using an adhesive or welding by ultrasound.

To facilitate centering of the two parts 5a, 5b of case 5 relative to each other, we use centering pins 18a, made in part 5a, which fit into holes 18b made in the part 5b.

In addition, the pull tab 15 can also be produced in two parts, like the case 5. The second part end 14 of the link will also have a protrusion 12 ', also produced by increasing the outer diameter of spring 3, locked in a housing 20 made in the pull tab 15.

To facilitate the installation of the protection on objects to protect that the link must cross, for example through the sieve of a racket, it is necessary to be able to remove the pull tab 15 and that the second end portion 14 of the link can slide inside the channel 6. In this case, replacement of the protrusion 12 'on the second end portion 14 of the link, provision may be made for a connection of the pull tab 15 by screwing on the turns of spring 3. We could, for example, make a thread in zipper 15 or simply use a washer (not shown), placed in a housing 22 made in the pull tab 15, which would be screwed on the turns of the spring 3 in the manner of a nut. We can also provide for an identical connection of the first end 4 of the link on the housing 5.

The protection device is detectable by detection devices using the detection principle electromagnetic. However, we can adapt the device according to the invention for use in detection radio frequency by adding a support (not shown) fixed on the case or on the link, allowing the fixing of a plate, used in detection radiofrequency and in a round form, rectangular or square.

• Le moyen de blocage, au lieu du piston 8 coopérant avec les spires du ressort 3, pourra être réalisé différemment, par exemple par pincement de la gaine 1. Toutefois, le moyen de blocage devra permettre à la gaine 1 de coulisser librement dans la direction de serrage et bloquer la gaine 1 dans la direction contraire,
• Le matériau métallique amagnétique ou faiblement magnétique du ressort 3 et de la tête de piston 9 pourra être un alliage à base de fer, de cuivre et/ou d'aluminium présentant des caractéristiques mécaniques en cisaillement au moins de l'ordre de 1300 à 1400 N/mm².

The invention is not limited to the embodiment described above only by way of example. In particular :

• The locking means, instead of the piston 8 cooperating with the turns of the spring 3, may be produced differently, for example by pinching the sheath 1. However, the locking means must allow the sheath 1 to slide freely in the direction tightening and locking the sheath 1 in the opposite direction,
• The non-magnetic or weakly magnetic metallic material of the spring 3 and of the piston head 9 may be an alloy based on iron, copper and / or aluminum having mechanical shear characteristics at least of the order of 1300 to 1400 N / mm ² .

Claims (10)

Device for protecting objects against theft, suitable for being detected remotely during crossing of a detection device, comprising a flexible attachment means capable of passing through or enclose the objects to be protected, tensile resistant and shear as well as a detectable element, characterized in that the attachment means comprises a sheath (1) of substantially non-magnetic material and the detectable element is a wire (2) detectable by detection devices using a detection principle electromagnetic, extending inside the sheath (1). Device according to claim 1, characterized in that the sheath (1) has a layer notched peripheral (3). Device according to one of claims 1 or 2, characterized in that the attachment means is secured by a first end (4) to a housing (5) having a channel (6) in which can slide, according to a tightening direction, a free part (7) of the means attachment, distant from the first end (4), the case also comprising a locking means unlockable cooperating with the free part (7) of the attachment means. Device according to claim 3 taken into account combination with claim 2, characterized in that the locking means consists of a piston (8) comprising a piston head (9) cooperating with notches of the notched layer (3) under the action of a spring return (10) and in that the piston head (9) is in substantially non-magnetic material. Device according to claim 1, characterized in that the sheath (1) has a wire reinforcement (21) placed inside the sheath and extending substantially parallel to the detectable wire (2). Device according to claim 1, characterized in that the sheath (1) has a sleeve (11), of material which is flexibly deformable, substantially non-magnetic, located between the notched layer (3) and the wire detectable (2). Device according to claim 6, characterized in that the sleeve (11) is a cable and in that the detectable wire (2) is placed in the cable. Device according to claim 3, characterized in that the first end (4) of the means attachment comprises a protrusion (12) blocked in a housing (13) made in the housing (5). Device according to claim 3, characterized in that a second end (14) of the means attachment includes a pull tab (15) which can be removable. Device according to claim 4, characterized in that the piston (8) has a body (16) made of magnetic material.

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