GB2453756A - Padlock type security seal locked by a rocker - Google Patents

Abstract

The padlock type security seal has a housing 1 and a J- or U-shaped hasp 2, the housing having first and second openings 3,4 to receive the legs of the hasp. The first opening 3 communicates with a third opening 5 of the housing to form a passage or channel 6 for a first leg 8 of the hasp. A locking mechanism 20 is provided within the housing. The locking mechanism is in the form of a rocker 20 with projections 22,23 which engage in notches 15, 6 in the legs of the hasp. It is biased by spring 24 to resist withdrawal of the first leg of the hasp through the first opening. The hasp is lockable within the housing such that it can only be removed by breaking or cutting of the first leg of the hasp at point of weakness 11.

Description

1 2453756

SECURITY SEAL

The present invention relates to a security seal of the padlock type. The seal has a housing which can receive the legs of a U-or i- shaped hasp. The hasp can be broken and removed from the housing, allowing the seal to be reused with a new hasp.

The seals are used to secure access doors to containers, transport vehicles and rooms to prevent illicit entry and to provide evidence of' illicit removal or attempted removal of said device. A typical example would be the bar trolley as used on airliners for the containment of in-flight saleable goods.

EP-A-0223 905 discloses a padlock-type seal which comprises a plastic housing having a pair of apertures for receiving a shackle formed of a U-shaped piece of wire.

* The shackle can be passed over the member to be locked and pushed into the housing, to irreversibly lock therein. The seal is released by cutting of the wire. This particular seal cannot be reused.

US-A-5230541 discloses a seal which is in the form of a fastener for cabinets.

The fastener is closed by means of a flexible, elongated band which engages on first and second latches within the fastener body. The band can be released for reuse.

WO-A-97/48603 discloses a seal having a J-shaped hasp which may be locked in the seal housing by means of a pressure sensitive catch. The seal can be opened by one leg of the hasp being cut. A product based on the design of WO-A-97/48603 is manufactured and sold by ITW Envopak under the name "Padseal" (registered trade mark). This product has a J-shaped hasp with parallel arms which are inserted into slots within the seal housing. The arms are locked within the housing by means of a sprung catch which is a hairpin shaped spring steel strip assisted by a helical spring.

The hasp is removed by one leg being cut, the lower part of that leg then being pulled out of the bottom of the housing, which allows the remainder of the hasp to be removed from the top. The hasp may bear an identification code or serial number.

EP-A-1672607 discloses another seal of the above type. A locking mechanism in the form of a V-shaped resilient clip is provided within the housing, which clip is biased to resist withdrawal of a first leg of the hasp. As above, the hasp is lockable within the housing such that it can only be removed by cutting of the first leg of the hasp. The legs of the hasp are connected together by a resilient hinge such that in a first, relaxed position the legs adopt a position in which they are not parallel, the legs being movable to a second, parallel position against the resilient force of the hinge for insertion into the housing.

To secure for example a container door using the above-described seal, one of the legs of the hasp is fed through holes in a pair of adjacent brackets, one bracket being fastened to the container door, the other fastened to the container, after which both legs are inserted into the seal body where they become entrapped by the locking mechanism which engages with a suitably shaped notch on each leg. When properly inserted the hasp cannot be removed from the seal without the use of a tool. Legitimate removal of the hasp is accomplished by cutting or breaking the longer hasp leg just above its entry point in to the seal, and pulling the remaining projecting end out of the seaJ.

A disadvantage of at least one known device is that when excessive force is applied to pull the hasp from the seal, the spring locking mechanism buckles under the load allowing the hasp to be removed from the body and reinserted showing no outward evidence of illicit removal.

It is one object of the invention to provide a seal of the above mentioned type which has a higher degree of security and tamper evidence.

According to a first aspect of the invention, there is provided a seal of the type comprising a housing and a J-or U-shaped hasp, the housing having first and second openings to receive the legs of the hasp, the first opening communicating with a third opening of the housing to form a channel for a first leg of the hasp, a locking mechanism being provided within the housing which is biased to resist withdrawal of at least one leg of the hasp through the first and/or second opening, the hasp being lockable within the housing such that it can only be removed by cutting of the first leg of the hasp, characterised in that the locking mechanism is a rocking or rotating member which has engaging means for engaging at least one leg of the hasp, the seal including resilient means for urging the said member into engagement with the leg.

The said member, hereinafter called a "rocker", preferably has a pair of projections, one on each of an opposite side thereof. The projections can extend into the channel and a bore of the housing, formed by the second opening, respectively. At least one leg of the hasp can have a notch, preferably both legs.

The rocker preferably pivots or rotates about a pivot pin formed on the housing.

The resilient means may be a spring which is mounted in the housing and acts on a shoulder of the rocker. The spring can urge the projections of the rocker into the channe] and a bore of the housing, formed by second opening.

An advantage of the invention is that because the rocker has no need to flex when the hasp is inserted it can be a rigid component and can be produced in any material with suitable strength characteristics. The rocker is thus preferably a unitary rigid member, preferably formed of a single piece (although it can be more than one piece, the parts being bonded or fixed together). Accordingly, the locking mechanism is no longer the weakest part of the device. The seal is therefore more resistant to tampering and is more secure.

Further advantages of the invention will be understood from the following detailed description of preferred embodiment of the invention which is described below, by example only, with reference to the accompanying figures. In the drawings: Figures 1 to 4 show a first embodiment of the invention in section, the different figures showing the connection and removal of the hasp in the seal body.

As shown in Fig 1, the padlock-type seal comprises as seal housing 1 and a hasp 2. The housing has first and second openings 3, 4, the first opening 3 communicating with a third openmg 5 at the opposite side of the housing to form a passage or channel 6. The second opening 4 communicates with a blind bore or passage 7. The passage 6 and passage 7 are substantially parallel to one another, within the housing body. The housing will generally be flat, with a thickness which is substantially less than the other two dimensions.

The hasp 2 is U-or J-shaped and in the embodiment shown has a longer leg 8 and a shorter leg 9. The hasp is rigid, formed for example of rigid plastics or of metal (e.g. steel). A weakened point 1] is formed in leg 8. Leg 8 has a notch 15 and leg 9 has a notch 16. The notches 15, 16 have leading angular shoulders and inclined trailing shoulders. The hasp may, for example, be 6 to 8 cm by 3 to 4 cm in its maximum dimensions, and 2 to 4 mm thick.

The parallel legs 8, 9 of the hasp are able to be engaged in the housing body, leg 8 passing through passage 6 and leg 9 passing into passage 7. The locking of the hasp within the housing will be explained in more detail below, with reference to Figs 2 and 3.

The locking mechanism 20 is in the form of a rocker which is allowed to rotate to a limited extent in the direction indicated by the arrow A about pivot 21. The pivoting of the rocker 20 may be achieved by means of the rocker having a central hole which fits on a pivot pin moulded into the housing.

The rocker is formed with arcuate surfaces which cooperate with correspondingly shaped arcuate surfaces of a space in the housing formed between the passages 6, 7. The rocker has projection 22 which can extend into passage 6 and opposite projection 23 which can extend into passage 7. The projections are preferably arranged so as to be on substantially diametrically opposite sides of the rocker, each being formed with inclined faces which act as ratchet teeth, permitting movement of the hasp legs in one direction but resisting movement in the other.

The rocker in practice is a thin, flat member, whose thickness may be the same or slightly thicker than that of the hasp. The rocker may be formed in one piece of metal (e.g. steel) or a suitable hard plastics material, for example. The rocker could be stamped or cast, or formed of sintered metal A spring 24 mounted in a seat in the housing urges the rocker to remain in the rest position against a suitable stop 25. The spring 24 acts against a shoulder 26 behind projection 23. In this rest position, the projections 22 and 23 extend into the passages 6 and 7.

As shown in Fig. 2, on insertion of the hasp into the housing, longer leg 8 will push projection 22 of rocker 20, acting as a cam surface, and thus rotate the rocker clockwise against the force of spring 24, moving the projections 22, 23 out of passages 6, 7. However, on further insertion of the hasp into the seal, as shown in Fig 3, the spring 24 rotates the rocker back anti-clockwise so that projection 22 engages into notch 15 of leg 8 and simultaneously projection 23 engages into notch 16 of leg 9.

Thus, Fig 3 shows the locked position of the seal. In practice, the hasp will of course be fitted over the element to be locked. In this position, the hasp is locked within the seal body. in particular, the hasp cannot be pulled out of the seal body opposite to the direction it was inserted, because the projections of rocker 20 are engaged in the notches of both legs of the hasp 2. The hasp cannot be removed because any movement of the hasp opposite to the direction of its insertion causes the notch 15 of the hasp to impart a rotation force on the rocker 20 via projection 22. However, rotation opposite to the direction of arrow A is not possible because projection 23 of the rocker also makes contact with notch 16 of the hasp thereby applying an equal and opposite force to the direction of hasp removal.

To remove the hasp it is cut or broken at point 11, see Fig 4, and the free end of the hasp limb 8 removed in the direction of the arrow. Upon breakage at the point of weakiiess 11, the lower part of leg 8 of the hasp is disconnected from the upper part.

The lower part of leg 8 can be pulled out from the bottom of the seal body, the leg passing over and depressing the projection 22 of rocker 20. This action rotates the rocker, against force of the spring 24, which in turn moves projection 23 out of passage 7, releasing leg 9. The top part of the hasp can be simultaneously pulled out from the top of the housing as seen in Fig 4. It should be noted, however, that if the leg 8 is removed from the bottom without the top part of the hasp immediately being pulled upwardly, the projection 23 of the rocker will not lock the leg 9, even though the spring 24 will move the projection into the notch 16 of leg 9. Upward movement of the hasp will simply pivot the rocker out of the way, as there is nothing in passage 6 to resist such movement.

The seal can now be re-used with a new hasp, which in practice will have a new identification code thereon for increased security. The removal of the hasp from the seal is done in the same manner as is known from the existing "Padseal" product (Registered trade mark) and from EP-A-1 672607.

The housing may be formed of a main body part and a cover, made of a suitable plastics material (for example glass-filled nylon/polyamide), the cover being sealed onto the housing body in a known fashion. The housing body is moulded so as to create the first passage 6 and the passage 7 described with reference to Fig I. In addition, the body is moulded to form a chamber for the rocker 20 and recess for the spring, between the passages. Typically, the cover would be welded on the housing body, pins on the cover locating within corresponding recesses in the housing body.

Alternatively, the housing may be formed as a sleeve into which an inner core is slotted and fixed, the core defining the passages for the hasp and the seat for the rocker. The sleeve and/or core could be metal, for example aluminium or steel.

In an alternative embodiment of the padlock according to the invention, which is not illustrated, instead of projection 23 of rocker 20 engaging with the notch 16 of the leg 9 of the hasp, it could instead be positioned so that it engages on shoulder 25 (Fig. 1) of the housing, which would provide a stop to resist anti-clockwise movement of the rocker in the position seen in Fig 3. In this version, the leg 9 of the hasp need not have a notch but otherwise the padlock is closed and opened as described in relation to the first embodiment.

Claims (10)

1. A seal of the type comprising a housing and a J-or U-shaped hasp, the housing having first and second openings to receive the legs of the hasp, the first opening communicating with a third opening of the housing to form a channel for a first leg of the hasp, a locking mechanism being provided within the housing which is biased to resist withdrawal of at least one leg of the hasp through the first andlor second opening, the hasp being lockable within the housing such that it can only be removed by cutting of the first leg of the hasp, characterised in that the locking mechanism is a rocking or rotating member which has engaging means for engaging at least one leg of the hasp, the seal including resilient means for urging the said member into engagement with the leg.

2. A seal according to any preceding claim, wherein the resilient means is a spring which is mounted in the housing and acts on a shoulder of the said member.

3. A seal according to claim 1 or 2, wherein the said member has a pair of projections, one on each of an opposite side thereof.

4. A seal according to claim 3, wherein the projections can extend into the channel and a bore of the housing, formed by the second opening, respectively.

5. A seal according to claim 4, wherein the resilient means urges the projections into the channel and the bore.

6. A seal according to any preceding claim, wherein at least one leg of the hasp has a notch.

7. A seal according to claim 6, wherein both legs have notches for engagement with the projections of the said member.

8. A seal according to any preceding claim, wherein the said member pivots about a pivot pin formed in the housing.

9. A seal according to any preceding claim, wherein the said member is a rigid unitary member.

10. A seal according to claim 9, wherein the said member is formed as one piece.