EP0612367A1

EP0612367A1 - Device for the temporary attachment of a security tagging element to objects

Info

Publication number: EP0612367A1
Application number: EP92912709A
Authority: EP
Inventors: Otto Schubert
Original assignee: Lift Verkaufsgerate-Gesellschaft Mbh
Current assignee: Lift Verkaufsgerate-Gesellschaft Mbh
Priority date: 1991-06-24
Filing date: 1992-06-23
Publication date: 1994-08-31
Also published as: WO1993000495A1; AU2013292A

Abstract

Un dispositif (1) permet de monter provisoirement un élément de marquage antivol électrique ou magnétique non linéaire (2) qui coopère avec un système électronique de surveillance sur des cassettes vidéo, sur des disques compacts ou sur des objets similaires (3) afin de les protéger contre un prélèvement non autorisé. Le dispositif (1) comprend un support rigide (4) d'élément de marquage antivol sous forme d'un cadre subdivisé (5) dont les parties (6, 8) peuvent être assujetties à l'objet à protéger (3) et verrouillées au moyen d'un ressort bimétallique (10) qui sert d'organe de verrouillage de manière à éviter le prélèvement non autorisé de l'objet (3). Le ressort bimétallique (10), qui forme un élément chauffant par résistance pouvant être électriquement connecté de l'extérieur, est assujetti, dans la position de fonctionnement du dispositif, sur le côté intérieur de la première partie (8) du cadre tourné vers l'objet. Dans sa position normale de fonctionnement à la température ambiante, le ressort bimétallique (8) verrouille cette partie (8) du cadre avec l'autre partie (6) du cadre, mais se met, lorsqu'il est chauffé, dans une position de libération dans laquelle les parties (6, 8) du cadre peuvent être séparées, ce qui permet d'ôter le support (4) d'élément de marquage antivol de l'objet à protéger (3).A device (1) makes it possible to temporarily mount a non-linear electric or magnetic anti-theft marking element (2) which cooperates with an electronic surveillance system on video cassettes, on compact discs or on similar objects (3) in order to protect against unauthorized debit. The device (1) comprises a rigid support (4) for the anti-theft marking element in the form of a subdivided frame (5) whose parts (6, 8) can be secured to the object to be protected (3) and locked by means of a bimetallic spring (10) which serves as a locking member so as to prevent unauthorized removal of the object (3). The bimetallic spring (10), which forms a resistance heating element which can be electrically connected from the outside, is fastened, in the operating position of the device, to the inner side of the first part (8) of the frame facing outwards. 'object. In its normal operating position at room temperature, the bimetallic spring (8) locks this part (8) of the frame with the other part (6) of the frame, but puts itself, when heated, in a position of release in which the parts (6, 8) of the frame can be separated, which makes it possible to remove the support (4) of the anti-theft marking element from the object (3) to be protected.

Description

Device for temporarily attaching a signal element to objects

The invention relates to a device for temporarily attaching a signal element, e.g. a non-linear electrical or magnetic circuit, on CD, audio, video cassettes or the like. Flat rigid objects to secure them against unauthorized removal, with a frame as a rigid signal element carrier, which can be attached to the object to be secured and with the help of a it is held, resiliently movable locking member can be locked against unauthorized removal from the object.

Surveillance systems for securing objects to be sold in business premises against unauthorized removal have already become widely known, cf. for example EP-A-91 581, EP-A-93 281 or EP-A-136 265; a so-called detector or surveillance "lock" with an HF transmitter and receiver is attached, for example in the area of the exit of the business premises, which e.g. interacts with an electronic circuit or with a magnetic stripe (see also US-A-4 075 618) and responds when an object with such a signal element is carried through the surveillance gate. These signal elements are usually in the form of labels, plates, strips or the like, and they are preferably detachably attached to the objects to be secured. For example, button-like carriers with insertable thorns (see, for example, EP-A-142 748 and also DE-A-2 539 035 and DE-A-2 321 584) are used for the temporary attachment of such signal elements to textile objects, whereby it is only possible with special unlocking devices available at the checkout to detach the mandrel and thus the button-like device from the respective item sold. Other proposals here were to inseparably connect the signal element to the object to be secured, and in the event of a sale the signal element would be rendered ineffective before the surveillance lock was passed

REPLACEMENT LEAF must be, cf. in addition to the aforementioned US-A-4075 618 also 0-A-88/03302. A disadvantage of these systems, however, is that the signal element is not reusable, apart from the fact that, with appropriate knowledge, it could possibly be removed from the object to be secured in an unauthorized manner, for example together with the packaging.

In AT-B-381 405 (and similarly in DE-A-35 18 029) it has also been proposed to secure CD disks, directly on the holder for the CD disk within the respective cassette to hold such a signal element with the aid of a securing or locking member, which can only be removed with special devices. Although this technique is very advantageous, it has the disadvantage that in the case of cassettes which contain several disks, each disk must be secured separately, so that e.g. in the case of cassettes with a content of four CD disks, for example in the case of opera recordings, four such security arrangements are required. In addition, buyers often want to buy a CD cassette with still intact packaging (usually a transparent plastic cover), in which case the security system described above - which requires the cassette to be opened beforehand - cannot be used.

The latter disadvantage also applies to a security system already in use, in which CD cassettes are accommodated in a separate frame, which serves as a signal element carrier, and which is thereby fixed to the CD cassette by resilient holding elements through slot-like openings that are present in the CD cassette on two opposite narrow sides thereof. These resilient holding elements can also only be released with special unlocking devices. Here, too, it is evidently necessary to remove the packaging sleeve that was usually originally present from the CD cassette. In addition, these frame-shaped signal element carriers are extremely bulky in the area of the resilient holding elements, so that when storing several objects side by side on a shelf again and again there is mutual jamming of the objects or the signal element carriers attached to them.

This disadvantage of bulkiness also applies to the fuse box according to EP-A-308 810, in which a lock with a button-like device as described in EP-A-142 248 already mentioned is to be used.

Another disadvantage of the known mechanical locking systems to be unlocked is that the failure rates for the mechanically unlocked locking frames are relatively high, and that the mechanical unlocking devices do not always work reliably. As an alternative to this, it has already been proposed to unlock the security or locking elements of the known security systems instead of mechanically and magnetically, i.e. To move into a release position, but such a magnetic unlocking is at least problematic in the event that the objects to be secured are magnetic tapes, such as in the case of audio cassettes or video cassettes, since then the recordings stored on the magnetic tapes are impaired , may be deleted.

On the other hand, safety devices have already been proposed, cf. for example US-A-3 718 922, US-A-3 806 910 (or the corresponding CA-A-1 007 336) and US-A-4 380 097, in which bimetallic springs are used as locking members which are heated when the power is supplied and thus fold over from a locking position into a release position. However, these known safety devices are pliers with a mandrel on a pliers arm, which is pierced, for example, by the respective - textile - object to be secured or passes through the object to be secured in an opening, and which in the closed position of the pliers device in an opening is picked up in the other gun arm. In its locking position, the bimetallic spring locks the two interlocking pliers arms against one another in the closed position Swivel. Pliers of this type are suitable as security devices for textile objects and the like, but not for objects such as CDs, audio cassettes, video cassettes, where piercing or reaching through is not possible.

It is therefore the object of the invention to provide a device of the type mentioned in the introduction, in which a completely unproblematic locking and unlocking on the flat, rigid object to be secured is possible, the signal element carrier nonetheless having no protruding, bulky parts, and also magnetic tapes can be secured without difficulty.

The inventive device of the type mentioned is characterized in that the frame is divided, the frame parts including the object to be secured can be positively connected to each other and locked by the locking member, and in that the locking member is formed by a bimetallic spring which is attached to one of the Frame parts on the inside of which in the working position faces the object, and which, in their normal operating position at room temperature, locks the frame parts on the object to be secured, but when heated, is in a release position in which the frame parts are separable from one another and thus from the object to be secured are removable.

With such a training, the above objective is advantageously met. As a result of the division of the frame, on the one hand simple manufacture of the frame parts, for example by injection molding, is made possible, and on the other hand it is advantageously achieved that the bimetal spring acting as a locking or securing element only with parts to be fastened to the object to be secured, but not with engages the object itself. As a result, any damage to the object, which may possibly be enclosed in a thin, easily tearable plastic cover, can be reliably avoided. The locking member in the form of the bimetal spring can furthermore be neatly space-saving in the interior of the respective frame part, whereby outwardly protruding parts can be avoided. The activation of the bimetallic spring by heat is also unproblematic for the objects to be secured, regardless of whether they are CD, audio or video cassettes or other such objects. In addition, the manufacture or assembly of such a frame with a bimetallic spring is comparatively simple and inexpensive, so that in addition to the advantage of easy handling, assembly and operation, that of simple and inexpensive manufacture is also achieved. Nevertheless, repeated use is of course possible.

The heat required for changing the bimetallic spring from the normal operating position, in which it effects the desired locking, into the release position can be provided, for example, through the material of the frame part. Apart from the fact that the material of the frame part would then have to be selected accordingly, there is a time delay due to the time for the heat transfer through the frame part until the bimetal spring folds over, and it is therefore particularly preferred according to the invention instead if the bimetal spring is an from outside the frame forms an electrically contactable resistance heating element. Contact pins that are connected to the bimetallic spring could protrude through the frame. However, in order not to complicate the manufacture of the present device and, moreover, to make access to the bimetal spring more difficult for unauthorized persons, it is particularly favorable if the bimetal spring can be electrically contacted via contact holes in the frame part for power supply. In the checkout area, the bimetal spring can then be enclosed through the contact holes in an electrical circuit of an electrical unlocking device in order to be heated by the current flowing through it to such an extent that it folds down into its release position. When this release position is reached, the power supply to the bimetal spring should expediently be switched off immediately, and An advantageous further development of the device according to the invention accordingly provides that a contact hole is provided in the frame part for making contact when the bimetal spring moves into the release position. The unlocking device available in the checkout area would accordingly be provided with a corresponding contact pin, which then comes into contact with the bimetallic spring through this contact hole when it swings into the release position, in which case an, optionally electronic, switch is then in the unlocking device can be operated to terminate the power supply to the bimetallic spring through the aforementioned power supply contact holes.

For the locking function as well as for the aforementioned resistance heating function, it has also proven to be advantageous if the bimetallic spring consists of two elongated, parallel strips which are fastened to the frame part at one end and connected to one another at the freely projecting end are. For effective resistance heating, it is advantageous if the two power supply contact holes are provided in the region of the fixed ends of the bimetal spring strips. On the other hand, for contact to be as safe as possible, it is advantageous if the contact-making contact hole is provided in the region of the freely projecting spring end where the strips are connected to one another.

The bimetallic spring can be attached to the signal element carrier in various ways, for example by casting in the frame material in the case of a manufacture of the frame parts by a casting technique or by ultrasonic welding. For simple assembly and also in order to be able to replace defective bimetal springs more easily, it has proven to be favorable if the bimetal spring is held in a form-fitting manner in a seat on the inside of the frame part, it being furthermore particularly advantageous in terms of manufacturing technology, if the bimetal spring is secured by a separate mounting plate on the inside of the frame part. For the form-fitting fixation of the bimetallic spring, it can also simply be provided here. that the bimetallic spring with at least one recess is placed on the inside of the frame part via a projection corresponding to this recess and the fastening plate is attached above it. On the other hand, it is also advantageous in terms of shape if the fastening plate is designed with a projection over which the bimetal spring with at least one recess is placed, the remaining part of the bimetal spring projecting from the end of the fastening plate. It is also advantageous if the mounting plate is strip-shaped and at the same time is provided for fixing the signal element. It is also advantageous for the locking function if the seat has an inclined seat for the flat bimetal spring.

For the releasable attachment of the bimetallic spring in order to be able to replace it, it is also advantageous if the mounting plate with snap-in projections is snapped into corresponding snap-in openings of the frame part.

For the form-fitting connection of the two frame parts, simple pin-hole arrangements can be provided, and for favorable handling it has also proven to be advantageous if one of the frame parts forms an insertion compartment for the object to be secured and the other of the frame parts through a cover strip closing the slot compartment frame part is formed. It is also advantageous for an unproblematic attachment of the cover strip to the slide-in frame part if the pin-hole arrangements are provided on the end faces of the cover strip, the cover strip being able to be brought into its closed position on the slide-in frame part by shifting in its longitudinal direction. Furthermore, it is advantageous if the bimetal spring is attached to the end strip frame part, in which case the attachment of the bimetal spring is easier to accomplish than in the case of an attachment inside the slide-in frame part, which is naturally more difficult to access inside.

In itself can be special on the slot frame part Elements are provided which interact with the bimetallic spring acting as a locking element, but it has proven to be advantageous if the bimetallic spring with its freely projecting end is arranged adjacent to one end face of the end strip, and when the end strip is pushed onto the insert compartment -Frame part can be snapped behind a projection on one side of this slide-in frame part, so as to lock the two frame parts against unauthorized detachment from one another. The projection practically forms an extension of a side wall of the slide-in frame part, so that additional elements, formations or the like can be avoided, since the bimetallic spring then works directly with this side wall of the slide-in frame part, which is lengthened in a projection. It is also advantageous here if, in the case of interconnected frame parts, the projection of the slide-in frame part ends at a distance from the inner surface of the cover strip facing it, by a gap for the passage of the bimetal spring in its release position when the cover strip is pushed off the slide-in compartment. Form frame part. With regard to the smoothest possible exterior, it is furthermore favorable if, next to the projection on the slide-in frame part, a shoulder is formed on the outside for the abutment of an end wall of the end strip.

An advantageous embodiment is also characterized in that the end strip has essentially the shape of an inverted "U" in cross-section and, in the working position, overlaps the upper edge of the object to be secured with the flange-like side walls forming the U-legs , whereas the inside of the upper web part of the end strip is at least partially spaced from the object to be secured in order to provide space for the bimetal spring. The bimetallic spring can simply be attached to the inside of the web part. Furthermore, simple training and assembly can be made possible in this respect, since the latching recesses for the lateral latching projections of the fastening plate in the flange-like Side walls of the end strip are provided.

In view of the above-mentioned easier accessibility of the inside of the end strip compared to the slide-in frame part, it is furthermore favorable if the signal element is attached to the inside of the end strip. This design also does justice to the fact that the slide-in frame part tends to be damaged more frequently due to its more complicated shape than the comparatively simple, stable end strip frame part, when the signal element is attached in the end strip frame part , while maintaining an exchange of the inexpensive slide-in frame part in the event of damage is easily possible.

The slot frame part should - in cooperation with the end strip - enclose the object to be sici such that a removal from the object is not possible without loosening and removing the end strip, but on the other hand the insert compartment frame part should the dimensions of the object to be secured if possible not significantly enlarge. In order to meet these contradicting requirements, it is particularly advantageous if the slide-in frame part is formed by three essentially flat, flat edge strips arranged at right angles to one another in pairs, with the two side edge strips parallel to one another at the front -and the back of the slide-in frame part run flat, flat cross strips. In this way, with only an insignificant increase in the dimensions of the object to be secured, a high stability of the frame enclosing the object is ensured, so that a violent breakup of the frame is not readily possible. Another advantage is the possibility of simple manufacture, and it is particularly advantageous according to the invention if the insert frame part is molded in one piece from clear plastic material, for example injection molded. Especially with regard to one Manufacture by injection or by injection molding, in order to get by with the simplest possible injection molds, is particularly advantageous if the transverse strips are offset from one another at the front or rear. In order to facilitate the closing of the frame, including an object to be secured, it has finally proven to be advantageous if a cross bar forms a guide stop for the end bar frame part, which abuts this cross bar in the working position.

The invention is explained in more detail below on the basis of particularly preferred exemplary embodiments illustrated in the drawing. In detail show:

Figure 1 is a vertical longitudinal section - generally along the line I-I in Figure 2 - by a device according to the invention, wherein a frame-shaped signal element carrier is attached and locked to a CD cassette to be secured.

FIG. 2 shows a plan view of the lower slide-in frame part of this frame-shaped signal element carrier according to FIG. 1;

Fig. 3 is a front view of this slot frame part;

4 shows a vertical cross section through this slide-in frame part according to line IV-IV in FIG. 3;

5 is an axonometric front view of the slide-in frame part;

6 shows an axonometric rear view of the slide-in frame part;

FIG. 7 shows an axonometric view of the end strip frame part of the frame-shaped signal element carrier according to FIG. 1;

FIG. 8 is an axonometric bottom view of this end strip frame part according to FIG. 7;

9 is a bottom view of the end molding frame part; 10 and 11 are detail sectional representations on a larger scale according to lines XX and XI-XI in FIG. 9; 12 is a plan view of those in FIGS. 9, 10 and 11 Dashed bimetal spring constituting the locking member of the present device;

13 shows a perspective view of a fastening plate for fixing this bimetal spring according to FIG. 12 on the inside of the end strip according to FIGS. 7 to 11;

FIG. 14 is a view of this fastening plate in the direction of arrow XIV in FIG. 13; 15 and 16 in enlarged detail sectional representations similar to that according to FIG. 1 the locking area of the present device, the bimetallic spring being shown in FIG. 15 in its locking position and in FIG. 16 in its release position reached after heating, in which the End strip can be pulled from the slot frame part in its longitudinal direction;

FIG. 17 in an axonometric bottom view similar to FIG. 8, a modified end strip frame part;

18 shows a longitudinal section through this modified end strip frame part;

Fig. 19 is a bottom view of this end frame part;

FIG. 20 is a perspective view of a modified, strip-shaped fastening plate which fits the end strip frame part from FIGS. 17 to 19;

FIG. 20A shows the detail indicated by A in FIG. 20 on a larger scale;

FIG. 21 shows a bottom view of this strip-shaped fastening plate according to FIG. 20;

22 shows a side view of this fastening plate according to FIGS. 20 and 21;

23 shows a longitudinal section of this strip-shaped fastening plate;

24 in an exploded view in cross section the modified end strip frame part and the associated strip-shaped fastening plate;

25 in a detailed sectional view similar to FIG. 15, the locking area of the device in which the 17 to 19 together with strip-shaped fastening plate according to FIGS. 20 to 23 are used; and

26 shows an electrical circuit diagram of an electrical unlocking device that can be used in combination with the present bimetal spring securing device.

1 shows a device, generally designated 1, which is currently regarded as the best embodiment for temporarily attaching an elongated signal element 2, for example a strip of magnetic material, which cooperates with a conventional electronic monitoring system which is not known per se and which is known per se or a non-linear electronic signal circuit, for example with a diode, as known per se (not shown) on an object 3 in a vertical longitudinal section. This object 3, which is, for example, a CD cassette, but which can also be formed by an audio cassette or video cassette, for example, is to be secured against unauthorized removal with the aid of the signal element 2. The object 3 is illustrated in FIG. 1 for the sake of a better overview only very schematically by a housing shown in section, without a holder for a CD disk or the CD disk itself being shown in detail.

The device 1 shown in FIG. 1 consists of a signal element carrier, generally designated 4, which is designed as an essentially rectangular, two-part frame 5. The lower, larger frame part 6 of this divided frame 5 forms, as will be explained in more detail below with reference to FIGS. 2 to 6, an insertion compartment 7 for the object 3, and for the sake of simplicity it is subsequently called an insertion compartment frame part 6 designated. The object 3, for example the CD cassette, is inserted into this insert compartment frame part 6, the insert compartment frame part 6 protruding slightly above the inserted object 3 on the two narrow sides. In this above area, the one below is even closer with reference to FIGS. 7 to 11 Upper frame part to be explained, which is formed by a sealing strip 8 and is also referred to below as a sealing strip frame part 8. This end strip 8 carries the signal element 2 in a recess 9, cf. In addition to FIG. 1, the representations in FIGS. 8 and 9 are also shown, this depression 9 being in the working position shown in FIG. 1 on the inside of the end strip 8 facing the object 3 and being inaccessible from the outside around the signal element 2 secure against access from outside.

On the inside of the end strip 8, a locking member in the form of a bimetallic spring 10 is also attached; This bimetallic spring 10 prevents, in the locking position or normal operating position shown in FIG. 1, in which it bears with its freely projecting end 11 on the slide-in frame part 6 as shown in FIG. 1 at the top right that the positive connection between the End strip 8 and the slide-in frame part 6, which is obtained by pin-hole arrangements 12, 13 to be explained in more detail below on the end faces of the end strip 8, is solved by pulling or pushing the end strip 8 lengthways in the direction of the arrow 14 . The exact operation of this locking member bimetal spring 10 will be explained in more detail below with reference to FIGS. 15 and 16. Before that, however, the construction and function of the individual components of the present system will be described with reference to FIGS. 2 to 14.

As already mentioned, the slide-in compartment frame part 6 is illustrated in detail in FIGS. 2 to 6. This slide-in frame part 6 is essentially formed by three flat, generally flat edge strips 15, 16 and 17, which are arranged at right angles to one another, the edge strip 16 forming the base of the frame part 6, from which extends at right angles upwards the two other edge strips 15, 17 extend parallel to one another. Between these parallel edge strips 15, 17 extend both on the Front as well as on the back of the slide-in frame part 6, cross bars 18, 19 or 20, 21, which, as can be seen in particular from FIG. 4, are offset in the vertical direction relative to one another. This on the one hand ensures an increased strength of this frame part 6, and on the other hand the manufacture in one piece is facilitated by injection molding, in particular made of clear plastic material. The production from a transparent or translucent plastic material is therefore recommended, since the object (3 in FIG. 1) can then be viewed from all sides without problems if it is enclosed in the slide-in frame part 6. The transverse strips 18 to 21 are of course to be provided with regard to their arrangement and width in such a way that the entire slide-in frame part 6 is sufficiently stable and that it is also impossible to move the object 3 downwards without removing the end strip 8, below the cross bar 21 (Fig. 4) to pull out of the slot frame part 6. If necessary, a further cross bar could also be provided on the back of the slide-in frame part 6 for this purpose, as is indicated by the broken line at 24 in FIG. 4.

The mutually parallel edge strips 15 and 17 are thickened on the outer side in the upper region of the slot compartment frame part 6 in order to have sufficient material strength in the region of the pin-hole arrangements 12, 13 for the positive connection of the two frame parts 6, 8 to ensure. 2, 3 and 5 it can be seen that a generally cylindrical pin 23 is provided for the positive connection on the right side as shown in these figures, the end face of this pin 23 for easier insertion into a corresponding hole 24th the end strip 8 (see FIG. 7, for example) is chamfered. On the other hand, in the left in FIGS. 2, 3 and 5, the edge strip 17 (which can be seen in FIG. 6 on the right side), a cross-sectionally rectangular hole 25 is provided, into which, when the end strip 8 is fastened to the slide-in frame part 6, an im Cross section more rectangular Pin 26 occurs on the corresponding end face of the end strip 8 (see FIGS. 8 and 9).

As can further be seen in particular from FIG. 3 in combination with FIG. 1, a shoulder or shoulder 27 is provided on the outside of the right-hand edge strip 15 of the insert compartment frame part 6, on which the end wall 28 of the end strip is in the operating position 8, in which the circular hole 24 is located, comes to rest with its lower edge.

The width of the edge strips 15, 16, 17 and thus of the slide-in compartment 7 is essentially equal to the thickness of the object 3 to be secured, the material thickness of these edge strips 15, 16, 17 depending on the material selected, for example being approximately 2 mm can. The thickness of the cross bars 18 to 21 or 22 can be approximately 1 mm. From this it can be seen that the slide-in frame part 6 increases the dimensions of the object 3 to be secured only insignificantly when attached to it, and the same applies to the upper end strip frame part 8, which in FIG. 4 as well as the object 3 for better illustration is indicated by dashed lines. It can also be seen that the cross section in the form of an inverted "U" having the upper end frame part 8 with the edge of its one leg of the "U" forming side wall 29 abuts the upper edge of the upper rear cross bar 20, so that this cross ¬ bar 20 forms a guide stop when sliding the end bar 8.

For the formation of the end strip 8 in detail, reference is then made to the representations in FIGS. 7 to 11. As mentioned, the end strip 8 has a generally U-shaped cross section, see. also Fig. 11, so that there is an overall groove-shaped design of the end strip 8, as can be seen in particular from Fig. 8. On one end of this channel-shaped end strip 8 is the end wall 28 already mentioned, in which the hole 24, which is circular in cross section, for the cylindrical pin 23 of the slide-in frame part 6 (see FIGS. 1 and 2, 3 and 5) ) located. A shortened end wall 30 is provided on the opposite end face of the trough-shaped end strip 8, on which the already mentioned cross-sectionally rectangular pin 26 is formed, which can also be provided with bevels on its projecting end face. The channel itself is defined by the already mentioned side wall 29, the side wall 31 parallel to it and defining the other leg of the "U" - which is somewhat wider than the side wall 29, cf. the representation in FIG. 11 - and the bottom wall 32 defining the web part of the "U". This bottom wall 32, also called the web part below, is provided over approximately 2/3 of its longitudinal extent with the depression 9 already mentioned in connection with FIG. 1, in which the signal element 2, not shown in FIGS. 8 and 9, is accommodated, and by lateral longitudinal strips 33, 34 is limited, which have the same height as the end wall 30. Adjacent to this receiving area for the signal element 2, a seat 35 is provided for the positive fit of the bimetal spring 10, this bimetal spring 10 consisting of a fork-shaped metal plate, the shape of which can be seen in FIG. 12.

Specifically, the bimetallic spring 10 has two mutually parallel strips or legs 36, 37, which at one end, the freely projecting spring end 11, cf. in particular also FIGS. 1, 15 and 16 are connected to one another. At the opposite end, the fastening end of the bimetallic spring 10, the strips 36, 37 are provided on the mutually facing edges with circular-arc-shaped recesses 38, 39 which fit exactly with a correspondingly circularly shaped projection 40 in the seat 35 of the end strip 8 (see. Fig. 8). This projection 40 continues in the direction of the end wall 28 in a strip-shaped projection 41, the width of which corresponds exactly to the width of the gap between the strips 36, 37 of the bimetallic spring 10. The legs or strips 36, 37 are also in the installed state of the bimetallic spring 10, which is shown schematically in FIGS. 9, 10 and 11 with dashed lines is indicated on the longitudinal edges or edges 42, 43 of the seat 35, so that the bimetallic spring 10 is secured by the elements 40 to 43 against all movements in the spring plane by the positive engagement. In order to fix the bimetallic spring 10 in its seat 35 and thus also to secure it against movements perpendicular to the spring plane, a separate fastening plate 44 is provided which, apart from FIG. 1, is shown schematically in FIG. 10 (in an exploded view) and otherwise in 13 and 14 is illustrated in more detail.

This mounting plate 44 is provided on two longitudinal sides with strip-shaped locking projections 45, 46, with which it can snap into corresponding elongated locking recesses 47, 48 in the side walls 29, 31 when it is in the direction of arrow 49 in Fig. 10 in place at the seat 35 is snapped. The mounting plate 44 is in profile, cf. 10 and 13, wedge-shaped, i.e. it increases in thickness from one end face to the other, and in a corresponding manner the seat 35 as a whole is also inclined in relation to the longitudinal extent of the end strip 8 or the web part 31 thereof, cf. in particular the representation in FIG. 10. As a result, the bimetal spring 10 assumes an oblique position in its normal operating position, as can also be seen from FIGS. 1 and 15, in which case in this oblique position it is free cantilevered spring end 11 protrudes downward and thus rests on the upper, projecting section or projection 50 of the edge strip 15 for locking the two frame parts 6, 8. This projection 50 ends, as can clearly be seen from FIGS. 15 and 16, in the assembled operating position at a distance from the inside of the web part 31 of the end strip 8, so that a gap 51 is left free to fold or bend the bimetallic spring 10, if it is heated accordingly, to create a free space for it, see the representation in Fig. 16 to thereby release the lock and to allow the end strip 8 to be pulled off from the slide-in frame part 6, see FIG. also arrow 52 in FIG. 16.

To mount the mounting plate 44 in the To facilitate the correct position on the seat 35, this fastening plate 44 is provided with a cutout 53, which can be seen in FIGS. 13 and 14, for example at least partially oblique, in a corner region, and in the seat 35 there is a corresponding extension in a corresponding corner region 54 molded. As a result, the mounting plate 44 can only be snapped into the end bar 8 in the correct position.

In the end strip 8 are finally in the zone of the seat 35 where the ends of the strips 36, 37 of the bimetallic spring 10 come to lie, for the power supply to the bimetallic spring 10, which also forms a resistance heating element, power supply contact holes 55, 56 are provided which extend through the bottom wall 31, cf. 11 through these contact holes 55, 56, through which contact pins 155, 156 of an electrical unlocking device 100 (not shown here) (see FIG. 26) can be brought into contact with the strip ends of the bimetallic spring 10 to be able to flow a current through the bimetal spring 10. This current through the bimetallic spring 10 heats it, and when a predetermined temperature is reached it moves from the normal operating position according to FIG. 15 given at normal temperature or room temperature to a release position as shown in FIG. 16 . This movement or this folding into the release position should be able to be detected automatically in the sense of automation during the unlocking process, and for this purpose a further contact hole 57 is provided in the bottom wall 31 of the end strip 8 in the region of the freely projecting spring end 11 which can protrude during the unlocking process a third contact pin 157 (FIG. 26) of the electrical unlocking device 100 (FIG. 26), which when the bimetal spring 10 is folded over from the position according to FIG. 15 into that according to FIG. 16 in contact with the bimetal spring 10 arrives, whereby this contact can be used to derive a switching signal for switching off the power supply to the bimetal spring 10 via the contact holes 55, 56. It follows from the above explanations that the construction described gives an extremely simple and yet extremely reliable locking mechanism, this locking mechanism being effective only in the area of the components which are to be provided for the attachment of the signal element 2, specifically in the area of the two frame parts 6, 8. This ensures particularly gentle treatment of the objects 3 to be secured.

If such an object 3 is to be temporarily equipped with a signal element 2 to secure it, this object 3 is simply inserted into the slide-in frame part 6 of the device described until its lower side abuts the lower edge strip 16. Then the end strip frame part 8 is placed in its longitudinal direction relative to the slide-in frame part 6, as shown in FIG. 6, offset to the right on the slide-in frame part 6, its rear side wall 29 coming into contact with the rear cross bar 20, after which the End strip 8 is shifted lengthwise to the left as shown in FIG. 1 until its rectangular pin 26 on the left end face in the rectangular hole 25 in the left side bar 17 or the cylindrical pin 23 on the right edge side 15 of the Insert frame part 6 engages in the circular hole 24 in the end wall 28 of the end strip 8. When the final assembly position is reached, which is shown in FIG. 1 and also in FIGS. 15 and 16, the bimetallic spring 10 previously pressed upwards against the inside of the web part 31 by the projection 50 of the edge strip 15 snaps downwards due to its spring force and snaps behind this protrusion 50, as shown in Figs. 1 and 15, &. that a reverse sliding movement of the end strip 8, as shown in Fig. 1, 15 and 16 to the right, is not possible in this working or operating position, since the bimetallic spring 10 as a locking member prevents this. However, as mentioned, when the bimetal spring 10 is heated, it moves in 16, and in this position the end strip 8 can be pulled off in the direction of arrow 52 from the slide-in frame part 6, the bimetallic spring 10 sliding along the top of the projection 50 of the edge strip 15 of the slide-in frame part 6. As soon as the pins 23, 26 have then been released from their associated holes 24, 25, the end strip 8 can simply be removed vertically upwards (as shown in FIGS. 1, 16) from the slide-in frame part 6.

In order to be able to insert the object 3 to be secured, for example a CD cassette, more easily into the slide-in frame part 6, it may also be expedient to dimension its width somewhat larger than the width of the CD cassette or the object 3 to be secured , and in order to nevertheless hold the object 3 in its position in the assembled state and to prevent its unwanted back and forth movement within the frame 5, a thickening can be provided on one of the edge strips 15, 17, for example the edge strip 15, in the upper end region 2, 3 and 6 at 58 as illustrated in FIGS. The object 3 lies against this thickening 58 in the operating position with its upper corner.

As can also be seen from FIG. 12, one leg 36 can be provided with a bevel 59 matching the shoulder 54 to facilitate the correct installation of the bimetal spring 10 in the seat 35; in this simple way it is ensured that the bimetallic spring 10 can only be placed in the correct position on the seat 35 during its assembly.

17 to 25 illustrate a modified embodiment of the end strip frame part 8 together with the fastening plate 44 ', this end strip frame part 8 together with the insert frame part 6 according to FIGS. 2 to 6 and together with a bimetallic spring 10 as shown in Fig. 12 can be used. The end bar 8 in the embodiment according to FIGS. 17 to 25 largely corresponds to that according to FIGS. 7 to 16, and accordingly the differences between the two embodiments are to be emphasized below. Above all, the appearance of the final bar 8 according to FIGS. 17 to 25, as far as its outside is concerned, the same as that shown in FIG. 7, so that a new description in this regard is not necessary.

17 to 19 is provided with a recess 9 which serves to receive a diode signal element (not shown) and is accordingly formed with a broadened central region 60 (for the diode body). Longitudinal strips 33, 34, which also serve as spacer elements for the strip-shaped fastening plate 44 ′ according to FIGS. 20 to 23, run laterally to this recess 9. This also results from the cross-sectional illustration according to FIG. 24. Moreover, this strip-shaped fastening plate 44 ′ is again made with the aid of lateral, elongated latching projections 45, 46, which in corresponding elongated latching recesses 47 and 48 in the side walls 29, 31 of the end strip 8 snap in, fixed in this end strip 8, cf. 24. Unlike in the previous exemplary embodiment, however, several such locking projections 45, 46 or recesses 47, 48 are now distributed over the length of the fastening plate 44 'or the end strip 8.

Another difference to the embodiment according to FIGS. 7 to 16 is that in the embodiment according to 17 to 25 the bimetal spring (see FIG. 12) is not attached to a seat 35 on the web part 32 of the end strip 8 itself, but to a seat 35 'on the strip-shaped fastening plate 44', on its side facing the web part 32 in the assembled position, which is shown at the top in FIGS. 20, 22 and 23. Essentially, the Si z 35 'corresponds in terms of its design to the seat 35 according to FIGS. 8 to 11, and it is accordingly designed with a round projection 40 and elongated, strip-shaped projections 41, 41' projecting from both sides thereof, see FIG. Figure 20A. The fastening plate 44 'is designed to be half-open on its end face which receives the bimetal spring (10 (FIG. 13), see in particular the illustration in FIG. 20A, in order to push the bimetal spring 10 onto the seat 35' enable. To achieve this semi-open configuration, bridge parts 61, 62 are provided on the upper side of the fastening plate 44 ', and offset to this is a bridge part located centrally on the underside of the fastening plate 44'

63, p. also Fig. 21 and 23. The height of the bridge parts 61 and 62 above the top of the remaining mounting plate 44 ', as shown in Fig. 22 and 23, corresponds to the height of the longitudinal strips 33, 34 of the end strip 8, so that in the assembled state tight attachment of the mounting plate 44 'on the inside of the web part 32 of the end strip 8 is ensured.

The final fixation of the bimetallic spring (10 in Fig. 12) in its seat 35 'in the assembled position of the mounting plate 44' within the end strip 8 is achieved by two side, knob-shaped projections

64, 65, which are provided on the inside of the end strip 8 in the angular areas, engage through corresponding lateral recesses 66, 67 in the mounting plate 44 'and come to rest firmly on the bimetallic spring 10, so that this bimetallic spring 10 due to the engagement of the edges of it Recesses 38, 39 on the round projection 40 and the contact of their inner leg sides on the elongated projections 41, 41 'and by the contact of the knob-like projections 64, 65, through which it is pressed into their seat 35', neither laterally nor is still vertically movable in the longitudinal direction.

Through the opening, which is left between the bridge parts 61, 62, current can be supplied to the legs 36, 37 of the bimetallic spring 10 via the contact holes 55, 56 in the web part 32 of the end strip frame part 8 in a manner analogous to that described above to bring about the folding of the bimetallic spring 10 described by the current flow and the resulting resistance heating, see FIG. 25, arrow 68, which enables unlocking of the frame parts 6, 8 in the manner described.

From Fig. 20, 21 and 23 it can then be seen that a recess 69 formed in the end bar 8 corresponding to the recess 9 with the widening 60 Fastening plate 44 'is present, a diode signal element finally being able to be inserted into the recess 9, 60 through this recess 69 when the fastening plate 44' is already fitted; then the recess 69 can be closed with the aid of an adhesive strip or the like, so that the fastening plate 44 ', in addition to the function of mounting the bimetallic spring 10, also fulfills the function of securing the signal element (2 in FIG. 1).

It should also be mentioned that the fastening plate 44 'in the state inserted into the end strip 8 is preferably flush with the end wall 30 (FIG. 17) from which the pin 26 with a rectangular cross section protrudes.

Finally, FIG. 26 shows a circuit diagram of an exemplary embodiment for an electrical unlocking device 100 which has three contact pins or general contacts 155, 156 and 157 in a spatial arrangement (not shown here) in accordance with the arrangement of the contact holes 55, 56 and 57 in the end strip frame part 8 of the device described, so as to be described in more detail below, via the contacts 155, 156 of the bimetallic spring 10 (not shown in FIG. 26) to supply the current for heating it as well as after the bimetal spring 10 has been folded over and thus when the contact 157 is made contact, this current supply is to be switched off again.

In particular, the unlocking device 100 has a transformer 102 which is to be connected to a voltage source, in particular the public AC supply network, via a microfuse 101 and which, for example, transforms the applied mains voltage down to a voltage of 2.5 V / 20 A. A control circuit 103 with a relay 104 and, on the other hand, a triac 105 are connected in parallel to the transformer secondary side with low voltage via the contacts 155, 156. The control circuit 103 also contains a diode rectifier circuit 106 with diodes D1 to D4 in a grating position and one parallel to the relay 104 Smoothing capacitor 107. This control circuit 103 is connected via a normally closed contact 108 'of a further relay 108, which (as will be explained in more detail below) after the bimetallic spring 10 has been flipped over and thus makes contact at contact 157, through which a bimetal spring contact 156. On the other hand the gate connection of the triac 105 is connected to the bimetal spring contact 156 via a normally open contact 104 'of the control circuit relay 104.

With the contact 157 for detecting the folding of the bimetallic spring 10, the already mentioned further relay 108 - to which a smoothing capacitor 110 is also connected in parallel - and also an acoustic and an optical signal generator in the form of a signal are then connected via a further Grätz rectifier 109 Speaker 111 or a light emitting diode (LED) 112 connected.

If, during operation, a device as described above with reference to FIGS. 1 to 25 is now inserted into the unlocking device, the contacts 155, 156 are closed via the bimetallic spring 10, as mentioned. The contact 108 'of the relay is in the rest position shown, and the AC voltage is rectified via the rectifier 106, with smoothing taking place in the capacitor 107. The coil of the relay 104 is now energized and the normally open contact 104 'closes so that the gate connection of the triac 105 is supplied with voltage. As a result, the triac 105 becomes conductive and current flows through the bimetal spring 10 and the triac 105, whereby the bimetal spring 10 - for example within a few seconds, e.g. in 1 to 3 seconds - is heated so much that it folds over.

If, as a result of this flipping, the bimetallic spring 10 now contacts the contact 157, the rectifier 109 is connected to the secondary AC voltage of the transformer 102, and the coil of the relay 108 is excited by the DC voltage smoothed with the aid of the capacitor 110. The relay 108 picks up and the normally closed contact 108 'switches over. This cuts off power to the rectifier 106 and relay 104, and the relay 104 drops , whereby the contact 104 'is opened again and the triac 105 is thus brought into the blocking state. As a result, the power supply to the bimetal spring 10 is interrupted.

At the same time, when the bimetallic spring 10 is folded down, an acoustic display and an optical display via the loudspeaker 111 or the LED 112 are effected in order to signal that the unlocking process has ended. The device can now be removed from the contacts 155, 156 and 157 and out of the unlocking device, and the end strip frame part 8 can be removed to the object 3 contained in the device, e.g. the CD to be able to take out.

If the invention was explained in more detail above on the basis of particularly preferred exemplary embodiments, further modifications and modifications are of course possible within the scope of the invention. For example, it is conceivable to rivet, pour or weld the bimetallic spring 10 in its seat 35 or 35 ', and it would also be conceivable to use conductive contact pins in the end strip 8 instead of the contact holes 55, 56 or 57 to be attached, e.g. to pour in, in which case corresponding contact areas of the electrical unlocking device would then cooperate with these contact pins. Furthermore, it is also conceivable to design the slide-in frame part 6 with corner reinforcements instead of the transverse strips 18 to 22 shown, or with full-walled front and rear sides. Another possible modification is to divide the frame 5 instead of at the top at another location, for example halfway up the frame, and to install the corresponding connecting and locking elements there, similar to those described above.

As mentioned, the slide-in compartment frame part 6 preferably consists of a clear plastic material, such as polyethylene terephthalate (PETP) or polycarbonate, while the closing strip frame part 8, like the fastening plate 44 or 44 ', can also consist of an opaque plastic material, which makes the choice of material easier, than a special heat resistance with regard to the heating of the bimetallic spring 10 is to be taken into account here. A suitable plastic material would be, for example, polybutylene terephthalate (PBTP), in particular with glass fiber reinforcement (for example 30%; for increased rigidity and temperature resistance).

The bimetallic spring 10, if it itself acts as an electrical resistance heating element, preferably consists of a material combination consisting, on the one hand, of a nickel-based alloy and, on the other hand, of a MnNiCu alloy or a NiMn or NiCr steel; the two sheets of these materials can be welded together, for example by rolling. It should also be mentioned here that it would also be possible to heat the bimetallic spring 10 indirectly, for example with its own electrical heating line or heating winding.

Claims

Claims:

1. Device (1) for temporarily attaching a signal element (2) cooperating with an electronic monitoring system, e.g. a non-linear electrical or magnetic circuit, on CD, audio, video cassettes or the like. Flat rigid objects (3) to secure them against unauthorized removal, with a frame (5) as a rigid signal element carrier (4), the The object (3) to be secured can be fastened and can be locked against unauthorized removal from the object (3) with the aid of a resiliently movable locking member, characterized in that the frame (5) is divided, the frame parts (6, 8) including the object to be secured (3) can be positively connected to one another and locked by the locking member, and that the locking member is formed by a bimetallic spring (10) which is attached to one of the frame parts (8) on the one in the Working position of the object (3) facing the inside is fastened, and which in its normal operating position at room temperature locks the frame parts (6, 8) on the object to be secured (3) lt, when heated, however, is in a release position in which the frame parts (6, 8) can be separated from one another and can thus be removed from the object (3) to be secured.

2. Device according to claim 1, characterized in that the bimetallic spring (10) forms a resistance heating element which can be electrically contacted from outside the frame (5).

3. Device according to claim 1 or 2, characterized gekenn¬ characterized in that the bimetallic he (10) consists of two elongated, parallel strips (36, 37) which are attached at one end to the frame part (8) and at the other, free projecting end (11) are interconnected.

4. Device according to claim 2 or 3, characterized gekenn¬ characterized in that the bimetallic spring (10) via contact holes (55, 56) in the frame part (8) for power supply can be electrically contacted.

5. Device according to claims 3 and 4, characterized gekenn¬ characterized in that the two power supply contact holes (55, 56) in the region of the fixed ends of the bimetallic strips (36, 37) are provided.

6. Device according to one of claims 2 to 5, characterized in that in the frame part (8) a contact hole (57) is provided for making contact when the bimetallic spring (10) moves into the release position.

7. Device according to claims 3 and 6, characterized in that the contact-making contact hole (57) is provided in the region of the freely projecting spring end (11) where the strips (36, 37) are connected to one another.

8. Device according to one of claims 1 to 7, characterized in that the bimetallic spring (10) is positively held in a seat (35, 35 ') on the inside of the frame part (8).

9. Device according to claim 8, characterized in that the bimetallic spring (10) is secured by a separate fastening plate (44; 44 ') on the inside of the frame part (8).

10. The device according to claim 9, characterized in that the bimetallic spring (10) with at least one recess (38, 39) over a correspondingly shaped to this recess projection (40, 41) on the inside of the frame part (8) and placed over it the mounting plate (44) is attached.

11. The device according to claim 9, characterized in that the fastening plate (44 ') is formed with a projection (40, 41, 41') over which the bimetallic spring (10) with at least one recess (38, 39) is placed, the remaining part of the bimetallic spring (10) from the mounting plate

(44 ') protrudes on the face.

12. Device according to one of claims 9 to 11, characterized in that the fastening plate (44 ') is strip-shaped and at the same time is provided for fixing the signal element (2).

13. Device according to one of claims 8 to 12, characterized characterized in that the seat (35; 35 ') has an inclined seat for the flat bimetal spring (10).

14. Device according to one of claims 9 to 13, characterized in that the fastening plate (44; 44 ') with latching projections (45, 46) in corresponding latching recesses (47, 48) of the frame part (8) is snapped.

15. Device according to one of claims 1 to 14, characterized in that the two frame parts (6, 8) by pin-hole arrangements (12, 13) can be positively connected to one another.

16. Device according to one of claims 1 to 15, characterized in that one of the frame parts (6) forms an insertion compartment (7) for the object to be secured (3) and the other of the frame parts (8) through one of the insertion compartment frame part ( 6) closing end strip (8) is formed.

17. Device according to claims 15 and 16, characterized in that the pin-hole arrangements (12, 13) are provided on the end faces of the end strip (8), the end strip (8) by moving in its longitudinal direction in their Ver closed position on the slot frame part (6) can be brought.

18. Device according to claim 16 or 17, characterized gekenn¬ characterized in that the bimetallic spring (10) is attached to the end frame part (8).

19. Device according to claims 17 and 18, characterized in that the bimetallic spring (10) with its cantilevered end (11) is arranged adjacent to one end face of the end strip (8), being when the end strip (8) is pushed on the slide-in frame part (6) can be snapped behind a projection (50) on one side of this slide-in frame part (6) so as to lock the two frame parts (6, 8) against unauthorized release from one another.

20. Device according to claim 19, characterized in that when frame parts (6, 8) are connected to one another, the projection

(50) of the slide-in frame part (6) ends at a distance from the inner surface of the end strip (8) facing it, to form a gap (51) for the passage of the bimetallic spring (10) in its release position when the end strip (8) is pushed off the slide-in frame part (6).

21. Device according to claim 19 or 20, characterized gekenn¬ characterized in that adjacent to the projection (50) on the slide-in frame part (6) outside a shoulder (27) for the abutment of an end wall (28) of the end strip (8) is formed .

22. Device according to one of claims 16 to 21, characterized in that the end strip (8) has in cross section essentially the shape of an inverted "U" and in the working position with the flange-like side walls (29, 29) forming the U-legs. 31) engages over the upper edge of the object (3) to be secured, whereas the inside of the upper web part (32) of the end strip (8) is held at least in some areas at a distance from the object (3) to be secured in order to provide space for the bimetal spring (10) to be provided.

23. The device according to claim 22, characterized in that the bimetallic spring (10) on the inside of the web part (32) is attached.

24. Device according to claim 22 or 23 with claim 14, characterized in that the latching recesses (47, 48) for the lateral latching projections (45, 46) of the fastening plate (44; 44 ') in the flange-like side walls (29, 31 ) the end strip (8) are provided.

25. Device according to one of claims 16 to 24, characterized in that the signal element (2) on the inside of the end strip (8) is attached.

26. Device according to one of claims 16 to 25, characterized in that the slide-in frame part (6) is formed by three substantially flat, flat, mutually angularly arranged edge strips (15, 16, 17), between the The two lateral, parallel edge strips (15, 17) on the front and rear of the slide-in frame part (6) run flat, flat cross strips (18 to 22).

27. The device according to claim 26, characterized in that the slide-in frame part (6) is formed in one piece from clear plastic material, e.g. is injected.

28. The device according to claim 26 or 27, characterized gekenn¬ characterized in that the transverse strips (18 to 22) are arranged offset on the front or back.

29. Device according to one of claims 26 to 28, characterized in that a cross bar (20) forms a guide stop for the end strip frame part (8) which bears against this cross bar (20) in the working position.