Security device

Abstract

 A security seal comprises an integral metal strip (1) formed by stamping and a clear plastics box (22) secured to a bent-over end portion of the strip. To use the seal the free end (3) of the strip is thrust into the slot (21) defined between the bent-over portions, and is then pulled back. This causes projection (14) to bend the tongue (5) up into an aperture (11) in the strip thereby preventing withdrawal of the end 3. Subsequent thrusting in of the end (3) is limited because projections extending from the side of the aperture (11) opposite the projection (14) catch holes (8) formed in the tongue (5).

Description

[0001] This invention relates to a security device which enables a container to be sealed in a manner which provides an indication if the container has been opened by breaking the seal.

[0002] Security devices are known which are not intended to prevent opening of a sealed container in the manner that a conventional lock is intended to prevent such opening, but which, on the other hand, do provide an indication if the container in question is opened. Such a device may, for example, include a flexible strip of suitable material bearing a distinctive serial number, means being provided for securing the opposite ends of the strip together after the strip has been located to prevent opening of a container. The means securing the ends of the strip together are designed such that after the ends have been secured together the strip cannot be reopened without destruction of the sealing means. Thus, once the container has been sealed it is impossible to open the container without destroying the security device and thus providing an indication that the container has been opened.

[0003] Security devices of the prior art have suffered from the disadvantage that they are formed of a plurality of discretely manufactured metal components which must be assembled together in order to provide the complete security device. As a result, the unit cost of such security device is relatively high bearing in mind that each can only be used for a single sealing operation.

[0004] According to one feature of the present invention there is provided a security device comprising: a flexible elongate strip having first and second ends; a tongue formed integrally with the strip and extending from adjacent the first end of the strip towards the second end of the strip, the tongue having a hole formed therein; and a locking mechanism located adjacent the second end of the strip for non-releasably receiving the first end of the strip, the locking mechanism comprising an end portion of the strip located sealed within a box having an entrance into which the first end can be pushed to lie substantially parallel to the said end portion, the said end portion being formed with an aperture, for receiving the tongue and with first and second projections integral with the said end portion and extending from opposite sides of the aperture, the first projection being positioned to bend the tongue into the aperture upon inserting the first end of the strip fully into the box and subsequently attempting to withdraw the first end, and the second projection being positioned to enter the hole and thereby prevent removal of the tongue from the aperture if a further attempt is made to push the first end fully into the box.

[0005] In the preferred embodiment of the present invention the security device includes a single metal strip in which the various apertures and projections necessary for functioning of the device are formed. Such metal strips can readily be stamped by a simple stamping process and can accordingly be manufactured very cheaply.

[0006] A further disadvantage of prior art security seals is that the components of the locking mechanism have not been visible through the casing or box in which the locking mechanism is housed. Accordingly, it is not possible by visual inspection to determine whether the locking mechanism has been correctly engaged in the first instance, and it may be possible to force the locking device in order to open the strip and subsequently to re-secure the strip into a loop form by means of a suitable adhesive. Although under these circumstances the locking mechanism will have been damaged the damage may not be apparent because the internal components of the locking mechanism are not visible.

[0007] In the preferred embodiment of the present invention the box of the locking mechanism is formed of a clear synthetic plastics material enabling ready visual inspection of the internal components of the locking mechanism in order to ensure that the locking mechanism has been properly engaged in the first instance, and has not been tampered with during a journey.

[0008] The above and further features and advantages of the present invention will become clear from the following description of a preferred embodiment thereof, given by way of example only, reference being had to the accompanying drawings, wherein:

FIGURE 1 illustrates the strip of a preferred embodiment of security device according to the present invention;

FIGURE 2 shows on an enlarged scale the lefthand end of the strip of Figure 1;

FIGURE 3 is a section on the line III-III of Figure 2;

FIGURE 4 illustrates on an enlarged scale the righthand end of the strip of Figure 1;

FIGURE 5 is a section on the line V-V of Figure 4;

FIGURE 6 shows the strip portion illustrated in Figure 2 after bending;

FIGURE 7 is a section on the line VII-VII of Figure 6;

FIGURE 8 is a view corresponding to Figure 7 showing the strip with lock box in position;

FIGURE 9 is a section on the line IX-IX of Figure 8;

FIGURE 10 is a view corresponding to Figure 6 and showing the strip in its operative locking configuration;

FIGURE 11 is a section on XI-XI of Figure 10; and

FIGURE 12 shows a further embodiment.

[0009] Referring firstly to Figures 1-5 there is shown an elongate strip 1 which has been provided with various apertures, cuts, and bends by a suitable forming operation, for example a single stamping operation. During this stamping operation a serial number or other suitable identifying information may be stamped on the central portion 2 of the strip to enable the strip to be uniquely identified when used. The material from which the strip is made is not critical, but it should be a material which is sufficiently flexible to enable the strip to be formed into a loop and to enable the operation of the security device described below to be effected. The material from which the strip is formed may be a thin metal ribbon.

[0010] Referring now to Figures 1,4, and 5 the portion of the strip 1 adjacent the righthand (as viewed in Figure 1) end 3 thereof is formed with an opening 4 which defines a tongue 5 integral with the strip 1 and extending from the edge 6 of the opening 4 adjacent the righthand end 3 towards the opposite end 7 of the strip. Two holes 8 are formed in the tongue 5 and in the embodiment shown in the drawings the righthand edge 6A of each hole 8 is aligned with the edge 6 of the opening 4.

[0011] At the opposite end of the strip 1 an end portion 9 of the strip located between a fold line 10 and the lefthand end 7 is formed with an aperture 11 having opposite edges 12,13 which extend transversely of the longitudinal direction of the strip. A first projection l4 extends from the edge 12 generally towards the righthand end 3 of the strip and a pair of second projections 15 extend from the edge 13 towards the lefthand edge 7 of the strip. The projections 14,15 are integral with the strip and are formed during stamping of the aperture 11 by making a generally V-shaped cut 16 in the material of the strip. Accordingly., the free end of the projection 14 is complementary to the generally V-shaped recess which separates the projections 15. During the stamping operation the projection 14 is bent slightly out of the plane of the major portion of the strip 1, the angle of bend being, for example, 7 degrees. During formation of the strip 1 a pair of circular apertures 17 and a pair of semi-cylindrical grooves 18 are formed in the strip symmetrical about the bend line 10. Finally, during formation of the strip 1 a rectangular aperture 19 is formed in the strip to the right of the fold line 10. A pair of cuts 40 extend from the aperture 19 to define a tab 41 which, together with the very end region 20 of the strip is bent out of the plane of the major portion of the strip during stamping.

[0012] It will be appreciated that the various holes, apertures, cuts, and deformations described above can be accomplished in a single stamping operation, and accordingly the strips 1 can be manufactured very cheaply by automated machinery.

[0013] Turning now to Figures 6 and 7 the next stage in production of the security device is to bend the strip 1 about the fold line 10 so that the apertures 17 and grooves 18 are respectively aligned and so that the projection 14 extends into the aperture 19. Accordingly, a slot 21 is formed between the end portion 9 and the underlying portions of the strip 1, the slot being traversed by the projection 14.

[0014] Referring now to Figures 8 and 9 a box 22 comprising lower and upper box portions 23,24 is next secured in position to enclose substantially the whole of the end portion 9 and the underlying portion of the strip. The box portions 23,24 are pre-formed of a clear synthetic plastics material and are secured together along the opposite longitudinal edges 25,26 of the box and along the end edge 27 of the box by heat sealing or ultra sonic sealing. any suitable means, for example by adhesive,X A pin 28 formed integrally with the box portion 23 extends through aligned apertures 17 and into an aperture 29 in the box portion 24. During assembly of the security device the pin 28 is deformed into locking engagement with a countersunk portion 30 of the aperture 29 in order to provide further means securing the box portions together. The box portions 23,24 once secured together cannot be removed unless they are broken.

[0015] The box 22 defines a locking chamber 31 to which access may be gained only via the slot 21 between the overlapping portions of the strip. The insertion of a tool into the chamber 31 via any small gap between the strip 1 and the lips 32 of the box is precluded by the transverse ridges 33 formed during the pressing of the grooves 18. The ridges 33 together with the pin 28 prevent the box 22 being removed from the end of the strip 1.

[0016] In order to use the above described security device the strip 1 is passed through the object to be secured and the strip is bent round into a closed loop configuration. The end 3 of the strip is then thrust into the slot 21 until it abuts pin 28. It will be noted that since the free end region of the strip is planar it can be thrust into the slot either way up, and accordingly if a twist is inadvertently introduced into the strip during closure this is of no consequence. Also, it will be noted that as the free end of the strip is thrust into the slot 21 the tab 41 is cammed downwardly as viewed in Figure 8 until it clears tongue 5 whereupon it will spring back to the position illustrated in Figure 8. Once this has occured withdrawal of the end 3 from the slot 21 will be impossible since attempted withdrawal will cause the tab 41 to engage the tongue 5 to prevent withdrawal. Further forward movement of the end 3 will cause the projection 14 to be cammed upwardly by the leading edge of the strip. The projection 14 will ride along the central bar 42 of the tongue 5 until the tongue 5 clears the projection whereupon the projection 14 will spring back to the position illustrated in Figure 8. It will be appreciated that the inherent resilience required for the action of the tab 41 and projection 14 is relatively small and is provided even if the strip 1 is made of a relatively ductile material.

[0017] Having thrust the end 3 of the strip into the slot 21 as far as it will go the security device is then set by attempting to withdraw the previously inserted end of the strip. During the attempted withdrawal the tongue 5 engages the upper surface of the projection 14 (as viewed in Figure 8) and is accordingly bent upwardly into the aperture 11. This bending causes a permanent set to be applied to the tongue 5 so that it extends out of the plane of the adjacent portions of the strip 1. The fully retracted position of the portions of the strip adjacent the end 3 is shown in Figures 10 and 11 in which it will be seen that the tongue 5 has been bent upwardly and extends through the aperture 11 to a point on the side of the end portion 9 remote from the slot 21. It will also be noted from Figure 11 that a further bend 34 has been formed in the projection 14 so that the projection 14 now lies substantially in the plane of the slot 21 rather than angled relative to this plane as in the pre-set condition.

[0018] If an attempt is now made to push the region of the strip 1 adjacent the end 3 back towards the pin 28 the tongue 5 remains in the upwardly bent condition illustrated in Figures 10 and 11, and accordingly the projections 15 will engage the holes 8 to prevent further forward movement of the end portion of the strip. Thus, once the tongue 5 has been bent to the position shown in Figures 10 and 11 it is impossible to remove the previously free end of the strip from the slot 21. Further, the configuration of the various portions of the strip precludes the insertion of a tool effective to assist in removing the end of the strip.

[0019] Because the box 22 is formed of a clear plastics material it is possible to inspect the operative components of the lock through the box in order to ensure firstly that the lock has been properly set, and secondly that no tampering with the lock has taken place.

[0020] The modified embodiment of the invention shown in Figure 12 is substantially the same as the above described embodiment except that an additional security feature is provided by two holes 43',44. Hole 43 is spaced from the adjacent groove 18 so that, after fitting the box 22, the hole 43 remains outside the box. The hole 44 is spaced from the end 3 of the strip by such a distance that, when the security device is correctly locked in position, the hole 44 is aligned with the hole 43. Thus, the aligned holes 43,44 provide a visual indication that the end 3 is correctly positioned. Further, if the strip is subsequently cut where it enters the box 22 and the cut end is thereafter thrust into the box in an attempt to hide the fact that the strip has been tampered with, this will be apparent from the fact that the holes 43,44 are no longer aligned. Finally, it will be noted that the opening 4A and the tongue 5A of the embodiment of Figure 12 are somewhat modified as compared with the arrangement of the other embodiment. The tongue 5A is defined at the lateral edges thereof by a pair of shear lines 45, and defines a 'single hole 8A. Operation of the embodiment of Figure 12 is as described above with reference to Figures 1 to 11.

Claims

1. A security device comprising: a flexible elongate strip having first and second ends; a tongue formed integrally with the strip and extending from adjacent the first end of the strip towards the second end of the strip, the tongue having a hole formed therein; and a locking mechanism located adjacent the second end of the strip for non-releasably receiving the first end of the strip, the locking mechanism comprising an end portion of the strip located sealed within a box having an entrance into which the first end can be pushed to lie substantially parallel to the said end portion, the said end portion being formed with an aperature for receiving the tongue and being provided with first and second projections extending from opposite sides of the aperture, the first projection being positioned to bend the tongue into the aperture upon inserting the first end of the strip fully into the box and subsequently attempting to withdraw the first end, and the second projection being'positioned to enter the hole and thereby prevent removal of the tongue from the aperture if a further attempt is made to push the first end fully into the box, characterised in that the first (14) and second (15) projections are formed integrally with the strip (1).

2. A security device according to claim 1, characterised in that the box (22) is transparent to allow visual inspection of the internal components of the locking mechanism.

3. A security device according to claim 1 or claim 2, characterised in that when the device is correctly locked, indicia (43,44) provided adjacent the first (3) and second (7) ends of the strip and located outside the box (22) are aligned.

4. A security device according to claim 3, characterised in that said indicia are holes (43,44).

5. A security device according to any preceding claim, characterised in that said first (14) and second (15) projections overlap in the axial direction of the strip (1).

6. A security device according to any preceding claim, characterised in that the second projection (15) comprises two laterally spaced apart projection parts, and wherein the free end of the first projection (14) is formed by material which is removed from between the projection parts.

7. A security device according to any preceding claim, characterised in that the strip (1) is a one piece metal stamping.

8. A security device according to any preceding claim, characterised in that the said end portion (9) is a bent over portion of the strip, the end portion(9) lying substantially parallel to the adjacent portion of the strip to define a slot (21) therebetween for the reception of the first end (14) of the strip.

9. A security device according to claim 8, characterised in that ridges (33) are formed on the strip (1) within but adjacent the entrance to the box (22) to prevent the insertion of a tool into the box (22).

10. A security device according to any preceding claim, characterised in that the portions of the strip (1) within the box (22) include an aperture (17) through which material (28) of the box (22) extends to prevent withdrawal of the box (22) from the strip (1).

Drawing