GB2316040A - Snap-fit tamper evident security seal with male/female connectors - Google Patents

Abstract

A security seal having male and female connectors 2, 3 disposed at opposite ends of an elongate tie portion 4, wherein the male connector 2 comprises axially-spaced first and second pairs of resilient arms 20, 21, and the female connector 3 comprises axially-spaced first and second recesses 36, 37 engageable with the arms 20, 21. The seal is configured such that partial insertion of the male connector 2 into the female connector 3 causes engagement of the first pair of arms 20 with the second recess 37 such that subsequent withdrawal of the male connector 2 from the female connector 3 with the seal intact is prevented. The resilient arms 20,21 are deflected on insertion into the female connector and include a land 26 at their free ends which engages a seat 38 in the recesses 36,37. A window (41, Fig 6) permits a visual check of full insertion. The male connector 2 is connected to the tie portion 4 by lugs 15 having tamper-indicating webs 50.

Description

Tamper Evident Security Seal This invention relates to snap-fit tamper evident security seals. Such seals may be used, for example, for detecting or discouraging unauthorised access during transit to the contents of tanker road vehicles.

Such seals generally include a tie comprising a flexible plastics band, male and female connectors being disposed at opposite ends of the tie. Following locking of the seal by interengagement of the male and female connectors the seal may be broken by the snapping of lugs which commonly connect the male connector to the tie. Such security seals are known which have plug and socket type connectors, wherein the plug comprises two frusto-conical members disposed end to end. An example is shown in GB 2163392A.

However a problem with such prior art seals is that they may be tampered with and disconnected without evidence of tampering.

A particular problem is that these seals may appear to be fully locked when only the first stage of the double locking process, that is engagement of each of the frusto-conical plug members with corresponding respective retaining members in the female connector, has been completed, making it possible to remove the seal without damage and to consequently reseal the seal with no signs of evident tampering.

In an effort to solve some of the above-mentioned problems, a male connector in the form of a tongue with laterally extending resilient projections has been developed which in use engages in a correspondingly shaped recess in the female connector.

The recess opens at one end to a passage to provide access for the tongue. Visual access is provided by a window for verification of full engagement of the tongue in the recess.

However complete insertion of the tongue into the recess requires substantial effort. If the requisite amount of effort is not expended it has still proved possible for the seal to have the appearance of being fully locked although only the first stage of the double locking process has been completed. In such security seals partial locking, i.e. completion of the first stage of the double locking process, allows removal of the tongue from the recess with no evident damage.

To make the last-mentioned type of security seal more secure a laterally extending bridge is provided adjacent the passage for insertion of the male connector. This bridge exerts pressure on the base portion of the prior art male connector, forcing its free end to rise in the recess. A further bridge is provided for exerting pressure on this free end towards the recess base, but the prior art arrangement is not effective unless full insertion is achieved.

One object of the invention is to overcome at least some of the above-mentioned problems.

Accordingly, the invention provides a snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion; said male connector means comprising axially spaced first and second male engagement means; and said female connector means comprising axially spaced first and second female engagement means engageable with said first and second male engagement means for retaining said first and second male engagement means; wherein said seal is configured such that partial insertion of said male connector means into said female connector means causes engagement of said first male engagement means with said second female engagement means such that subsequent withdrawal of said male connector means from said female connector means with the seal intact is prevented.

Preferably, said seal is configured such that full insertion of said male connector means into said female connector means causes substantially simultaneous engagement of said first and second male engagement means with said first and second female engagement means respectively such that subsequent withdrawal of said male connector means from the fully inserted position with the seal intact is prevented.

Preferably, said first and second male engagement means comprise respective first and second resilient arm means and said first and second female engagement means comprise respective first and second retaining means defined by a recess in said female connector means.

Preferably, engagement of said first and second male engagement means with said first and second female engagement means respectively is effected by resilient deflection of said first and second arm means and subsequent substantially simultaneous release of said first and second arm means into first and second retaining means respectively.

Preferably, engagement of said first male engagement means with said second female engagement means is effected by resilient deflection and subsequent release of said first arm means into said second retaining means.

Preferably, said arm means comprise respective first and second pairs of resilient arms extending laterally from said male connector means and axially away from the free end thereof.

Preferably, each said arm has a land at its free end and said retaining means have corresponding seats, withdrawal of a fully inserted said male connector means from said female connector means with the seal intact being prevented by engagement of the lands of said first and second arm means with the corresponding seats of said first and second retaining means respectively; and withdrawal of a partially inserted male connector means from the female connector means with the seal intact being prevented by engagement of the lands of said first arm means with the seats of said second retaining means.

Preferably, said arms are configured such that a substantial lateral resilient deflection of each arm is necessary prior to its release into said retaining means as said male connector means is inserted, and said release results in an easily detectable movement of said arms into an easily visually detectable locked position.

Preferably, said first pair of arms is disposed at the free end of said male connector means and the flexibility of these arms is facilitated by provision of a transversely extending groove at the centre of the free end resulting in first arm means with an "M" configuration.

In use, predetermined levels of force may be required to fully insert said male connector means such that full and irreversible insertion can be performed easily by hand in one movement.

Preferably, said female connector means is provided with a window for viewing said retaining means and said male connector means when inserted therein for verifying full insertion of said male connector means.

The male connector means, said tie portion and said female connector means excluding said window preferably comprise a unitary plastics moulding.

A support may be provided for pressing said male connector means towards the recess base for facilitating retention of said male connector means in said recess regardless of whether the male connector means is partially or fully inserted in said recess.

The invention also includes a snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion; said male connector means having at least one resilient arm means; said female connector means having corresponding retaining means for retaining said arm means; wherein said seal is configured such that insertion of said male connector means into said female connector means causes a substantial lateral resilient deflection of said arm means and subsequent easily detectable movement of said arm means into an easily visually detectable locked position in said retaining means.

Preferably, said arm means comprises a pair of arms disposed at the free end of said male connector means and the flexibility of these arms is facilitated by provision of a transversely extending groove at the centre of the free end resulting in arm means with an "M" configuration.

The female connector means preferably has a recess which defines said retaining means and further defines a projection which corresponds to said groove and projects into said groove when said male connector means is fully inserted in said recess for facilitating alignment of the axis of said male connector means with the axis of said recess.

The invention also includes a snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion, wherein said male connector means is connected to said tie portion by breakable lugs; wherein said seal further comprises tamper indicating thin webs which provide irreversible visual indication when damaged.

Preferably, the force necessary to break said webs is less than the force necessary to break said lugs and/or the temperature necessary to damage said webs is lower than the temperature necessary to damage said lugs.

The invention also includes a snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion; said male connector means having at least one arm means having resilient arms extending laterally therefrom and axially away from the free end thereof, each said arm having a respective land at its free end; said female connector means having a recess therein defining retaining means for retaining said arm means, said retaining means having seats for engaging respective said lands; withdrawal of said male connector means from said female connector means with the seal intact being prevented by engagement of said lands with respective corresponding said seats; wherein substantially the entire surface area of each land is engageable with a corresponding said seat.

The invention also includes a snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion; said male connector means having at least one laterally extending arm means; said female connector means having a recess therein defining retaining means for retaining said arm means; said recess opening at a first end thereof into a passage for inserting said male connector means therethrough having a depth transverse to the lateral direction substantially equal to the thickness of said male connector means transverse to the lateral direction; wherein said passage extends axially substantially as far as said retaining means such that a wall of the passage forms a support which presses the male connector means towards the recess base both when fully and when partially inserted in said recess.

The invention also includes a snap-fit tamper evident security seal having male and female connector means; wherein outer surfaces of axially and transversely extending laterally disposed sides of said female connector means have a curved configuration with no flat portions, for hindering effective application of gripping tools to force open said seal.

In order that the invention may be well understood, an embodiment thereof will now be described, by way of example only, with reference to the accompanying drawings in which: Fig. 1 is a top plan view of a tamper evident security seal having a tie portion with a female connector disposed at one end thereof and a male connector disposed at its other end; Fig. 2 is cross-sectional view of the security seal taken on II-II in Fig. 1 with a window of the female connector removed; Fig. 3 is a bottom plan view of the security seal; Fig. 4 is an end view of the security seal showing the female connector with its window removed; Figs. 5, 5A and 5B are top plan, side and end views respectively of the window of the female connector; Fig. 6 is a cross-sectional side view of a portion of the security seal in the sealed condition showing interconnected male and female connectors; Fig. 7 is an enlarged view of the male connector; and Fig. 8 is an enlarged view of the female connector.

Referring now to Figures 1 to 3, a tamper evident security seal 1 has male and female connectors 2 and 3 disposed at opposite ends of an elongate tie portion 4. The seal is made by inserting the male connector 2 into the female connector 3, and may be broken at a point of weakness provided by lugs 15 connecting the male connector 2 to the tie portion 4. Grips to facilitate manipulation of the seal 1. are provided by arrays of studs 10, 11, 12, 13 formed on opposite faces of the tie portion 4 adjacent the male and female connectors.

The male and female connectors 2 and 3 are shown in more detail in Figures 6 to 8. The male connector (see Fig. 7) has male engagement means which are resiliently deflectable arm means comprising first and second axially spaced pairs 20 and 21 of resilient arms 25 extending laterally from the male connector 2 and axially away from the free end thereof. Each arm 25 has a land 26 at its free end. The lateral extent of the arms of each pair 20, 21 from the body portion 27 of the male connector 2 is similar and is substantial, to enable a degree of resilient deflection which is easily visually detectable. To facilitate flexure of the arms 25 of the first pair 20 which are disposed at the free end of the male connector 2, a groove 30 is provided in this free end centred on the axis of the connector 2 and extending transversely to the lateral direction in which the arms 25 extend, such that the first pair of arms 20 forms an "M". The groove 30 is formed such that the radii of the shoulders of the "M" continue the thickness of the arms 25 around an arc.

The male connector 2 is of substantially uniform thickness (ie in a direction transverse to the lateral extent of the arms 25).

The female connector 3 (see Figure 8) has a relatively thick body of sturdy construction to resist any forcible attempt to gain entry to the female connector in the sealed condition (for example by pliers) or at least to ensure that the application of the high force necessary to gain entry will result in visible damage to the body to indicate tampering. Outer surfaces 55 of axially and transversely extending laterally disposed sides of the female connector 3 have a curved configuration with no flat portions which, whilst being attractive, also hinder effective application of gripping tools eg. pliers to force open the seal 1.

A recess 35 is formed in the female connector 3, the inner side walls of which define axially spaced first and second female engagement means which are retaining means 36 and 37 for retaining the first and second arm means respectively. Each retaining means has seats 38 for engagement with corresponding lands 26 of the arms 25 of the male connector 2. The recess 35 also defines projections 39 configured to cause resilient deflection of the arms 25 during insertion of the male connector 2 into the female connector 3 and subsequent release of the arms 25 into one of the retaining means 36, 37 where they regain their unstressed condition and lock the connectors 2, 3 together to form an activated seal. The recess 35 also defines a projection 51 which corresponds in shape to the groove 30 and is positioned to project into the groove 30 when the male connector 2 is fully inserted in the female connector 3. This facilitates alignment of the respective axes of the male connector 2 and the female connector 3 and tends to centre the male connector 2 in the recess 35 thus improving retention of the male connector 2.

The recess 35 opens at one end into a passage 40 (see Figure 4) in the female connector 3 for inserting the male connector 2 therethrough and into the recess 35.

A tamper resistant window 41 (see Figs. 5, 5A, 5B, 6) of translucent material, which may be transparent, is provided to enable viewing of the retaining means 36, 37. A visual check can therefore be made in order to verify full insertion of the male connector 2 in the female connector 3 to confirm that a fully effective seal is made. Serial numbers may be provided on the window to hinder effective non-evident tampering by replacement of a damaged window with a similar replacement window. A concealed inscription may be provided on the seal.

The depths of the passage 40 and the recess 35 transverse to the lateral direction are substantially equal to the thickness of the male connector 2. The passage 40 extends axially substantially as far as the seats 38 of the second retaining means 37 such that a wall of the passage 35 forms a support 45 which presses the male connector means towards the base of the recess 35. This pressing action is effective both when the male connector 2 is partially inserted and when it is fully inserted in the recess 35, and facilitates retention of the male connector 2 in the recess 35.

In order to make a seal, the tie portion 4 of the seal 1 is looped about an appropriate securing point and the male connector 2 is inserted into the female connector 3.

Insertion of the male connector 2 initially causes resilient deflection of the first pair of arms 20 and is followed by release of these arms into the second retaining means 37.

Further insertion of the male connector 2 causes a second resilient deflection of the first pair of arms 20 and a resilient deflection of the second pair of arms 21.

Yet further insertion of the male connector 2 causes release of the first pair of arms 20 into the first retaining means 36 and substantially simultaneous release of the second pair of arms 21 into the second retaining means 37 to provide simultaneous double locking.

Before the last mentioned simultaneous release is effected the male connector 2 is only partially inserted in the female connector and the seal is only partially made. However, complete withdrawal of the male connector 2 from the female connector 3 is prevented by engagement of the lands 26 of the first pair of arms 20 with the seats 38 of the second retaining means 37.

Following simultaneous release of the first and second pairs of arms 20, 21 withdrawal of the male connector means 2 from the fully inserted position is prevented by engagement of the entire surface area of each of the lands 26 of the first and second pairs of arms 20, 21 with the corresponding seats 38 of the first and second retaining means 36, 37.

Careful determination and selection of the degree of flexure of the pairs of arms 20, 21 and their resistance to resilient deflection facilitates predetermination of the force required to fully insert the male connector 2 into the female connector 3. Such full insertion is essential to provide an effective tamper-proof seal, and formation of such a seal in an industrial environment is promoted by ensuring that full insertion can be achieved easily by hand in a single movement.

The level of force required to fully insert the male connector 2 is set at a relatively low level to facilitate performance in one movement. Furthermore, release of the arms 25 during partial and full insertion can be detected when making the seal because the substantial resilient deflection necessary prior to release results in an easily detectable movement which may be felt and/or heard and in an easily visually detectable locked position which can be confirmed visually by means of the window 41.

It is thus unlikely that a partially made seal will be mistaken for a fully made seal because of the distinct differences in appearance of the seal in the two conditions, unlike the prior art which makes such mistakes more likely.

However, even in the event a seal has been only partially made, moderately effective locking is still provided. Also, because the force required to fully insert the male connector 2 is not high, a particular problem of the prior art is overcome, namely, that in some prior art male connectors, the arms of which are relatively thick and not so readily flexible, resistance to insertion is such that the male connector lodges in its recess in the partially locked condition but gives the feel and appearance of being fully locked.

With the male connector 2 partially or fully inserted in the recess 35 the support 45 presses the base portion 28 or body 27 of the male connector towards the base of the recess 35 thus facilitating retention of the male connector 2 in position in the recess 35.

The male connector 2, tie portion 4 and female connector 3 excluding the window 41 comprise a unitary plastics moulding, and the male connector 2 is connected to the tie portion 4 by lugs 15 which are breakable to release the seal. Conventional tamper evident qualities may be provided by the lugs 15 in that they may plastically deform and/or change colour on breaking. However, between the lugs, tamper indicating thin webs 50 are also provided which extend between the tie portion 4 and the male connector means 2. These webs 50, or threads, are very fine and provide visual indication when damaged.

The webs 50 are constructed such that the force necessary to break them is less than the force necessary to break the lugs 15 and the temperature necessary to damage or destroy them is less than the temperature necessary to damage or destroy the lugs 15.

The webs 50 are virtually impossible to repair or replace, so that even if the lugs 15 are broken and made good again, the webs will provide an indication of tampering (e.g. by melting). Because the webs 50 are not restorable to their original appearance following damage, the visual indication of damage caused by tampering is irreversible.

It should be understood that although the exemplary seals described above preferably have two male engagement means and two female engagement means, such seals may be provided with more than two male and more than two female engagement means. Similarly, some such seals may be provided with only one male and one female engagement means.

Claims (23)

CLAIMS:

1. A snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion; said male connector means comprising axially spaced first and second male engagement means; and said female connector means comprising axially spaced first and second female engagement means engageable with said first and second male engagement means for retaining said first and second male engagement means; wherein said seal is configured such that partial insertion of said male connector means into said female connector means causes engagement of said first male engagement means with said second female engagement means such that subsequent withdrawal of said male connector means from said female connector means with the seal intact is prevented.

2. A seal as claimed in claim 1, wherein said seal is configured such that full insertion of said male connector means into said female connector means causes substantially simultaneous engagement of said first and second male engagement means with said first and second female engagement means respectively such that subsequent withdrawal of said male connector means from the fully inserted position with the seal intact is prevented.

3. A seal as claimed in claim 1 or 2, wherein said first and second male engagement means comprise respective first and second resilient arm means and said first and second female engagement means comprise respective first and second retaining means defined by a recess in said female connector means.

4. A seal as claimed in claim 3, wherein engagement of said first and second male engagement means with said first and second female engagement means respectively is effected by resilient deflection of said first and second arm means and subsequent substantially simultaneous release of said first and second arm means into said first and second retaining means respectively.

5. A seal as claimed in claim 3 or 4, wherein engagement of said first male engagement means with said second female engagement means is effected by resilient deflection of said first arm means and subsequent release of said first arm means into said second retaining means.

6. A seal as claimed in any one of claims 3 to 5, wherein said arm means comprise respective first and second pairs of resilient arms extending laterally from said male connector means and axially away from the free end thereof.

7. A seal as claimed in claim 6, wherein each said arm has a land at its free end and said retaining means have corresponding seats, withdrawal of a fully inserted said male connector means from said female connector means with the seal intact being prevented by engagement of the lands of said first and second arm means with the corresponding seats of said first and second retaining means respectively; and withdrawal of a partially inserted male connector means from the female connector means with the seal intact being prevented by engagement of the lands of said first arm means with the seats of said second retaining means.

8. A seal as claimed in claim 6 or 7, wherein said arms are configured such that a substantial lateral resilient deflection of each arm is necessary prior to its release into said retaining means as said male connector means is inserted, and said release results in an easily detectable movement of said arms into an easily visually detectable locked position.

9. A seal as claimed in claim 6, 7 or 8 wherein said first pair of arms is disposed at the free end of said male connector means and the flexibility of these arms is facilitated by provision of a transversely extending groove at the centre of the free end resulting in first arm means with an "M" configuration.

10. A seal as claimed in any one of the preceding claims, wherein, in use, predetermined levels of force are required to fully insert said male connector means such that full and irreversible insertion can be performed easily by hand in one movement.

11. A seal as claimed in any one of claims 3 to 10, wherein said female connector means is provided with a window for viewing said retaining means and said male connector means when inserted therein for verifying full insertion of said male connector means.

12. A seal as claimed in claim 11, wherein said male connector means, said tie portion and said female connector means excluding said window comprise a unitary plastics moulding.

13. A seal as claimed in any one of claims 3 to 12, wherein a support is provided for pressing said male connector means towards the recess base for facilitating retention of said male connector means in said recess regardless of whether the male connector means is partially or fully inserted in said recess.

14. A snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion; said male connector means having at least one resilient arm means; said female connector means having corresponding retaining means for retaining said arm means; wherein said seal is configured such that insertion of said male connector means into said female connector means causes a substantial lateral resilient deflection of said arm means and subsequent easily detectable movement of said arm means into an easily visually detectable locked position in said retaining means.

15. A seal as claimed in claim 14, wherein said arm means comprises a pair of arms disposed at the free end of said male connector means and the flexibility of these arms is facilitated by provision of a transversely extending groove at the centre of the free end resulting in arm means with an ''M' configuration.

16. A seal as claimed in claim 15, wherein said female connector means has a recess which defines said retaining means and further defines a projection which corresponds to said groove and projects into said groove when said male connector means is fully inserted in said recess for facilitating alignment of the axis of said male connector means with the axis of said recess.

17. A snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion, wherein said male connector means is connected to said tie portion by breakable lugs; wherein said seal further comprises tamper indicating thin webs which provide irreversible visual indication when damaged.

18. A seal as claimed in claim 17, wherein the force necessary to break said webs is less than the force necessary to break said lugs.

19. A seal as claimed in claim 17 or 18, wherein the temperature necessary to damage said webs is lower than the temperature necessary to damage said lugs.

20. A snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion; said male connector means having at least one arm means having resilient arms extending laterally therefrom and axially away from the free end thereof, each said arm having a respective land at its free end; said female connector means having a recess therein defining retaining means for retaining said arm means, said retaining means having seats for engaging respective said lands; withdrawal of said male connector means from said female connector means with the seal intact being prevented by engagement of said lands with respective corresponding said seats; wherein substantially the entire surface area of each land is engageable with a corresponding said seat.

21. A snap-fit tamper evident security seal having male and female connector means disposed at opposite ends of an elongate tie portion; said male connector means having at least one laterally extending arm means; said female connector means having a recess therein defining retaining means for retaining said arm means; said recess opening at a first end thereof into a passage for inserting said male connector means therethrough having a depth transverse to the lateral direction substantially equal to the thickness of said male connector means transverse to the lateral direction; wherein said passage extends axially substantially as far as said retaining means such that a wall of the passage forms a support which presses the male connector means towards the recess base both when fully and when partially inserted in said recess.

22. A snap-fit tamper evident security seal having male and female connector means; wherein outer surfaces of axially and transversely extending laterally disposed sides of said female connector means have a curved configuration with no flat portions, for hindering effective application of gripping tools to force open said seal.

23. A snap-fit tamper evident security seal substantially as described herein with reference to the accompanying drawings.