GB2088468A - Locking device - Google Patents

Abstract

A seal comprises a flexible strap 1 adapted to be looped about the neck of a container and secured in that looped condition. A tubular housing 2 is provided at one end of the strap and a ratchet mechanism, formed by apertures 5 through the strap 1 and a tooth 6 integral with the housing 2, enables the strap to be passed in one direction through a passage 3 of the housing 2 but resists withdrawal of the strap 1 in the opposite direction. A locking member 10 is attached to the housing 2 by frangible connections which are broken to move the member 10 into an operative position at which a peg 12 engages within an aperture 5 of the strap 1. Retaining means in the form of shoulders on side walls of the locking member 10 function to prevent return of the locking member 10 from its operative position. <IMAGE>

Description

SPECIFICATION Locking device This invention relates to a locking device of the kind having a strap which can be looped about the neck of a container such as a cash bag and locked in that position. The invention is particularly concerned with such devices which can be tightly drawn about the container neck and cannot be released without visible damage. It will be convenient to describe the invention with reference to cash bags.

It is known to close the neck of a cash bag by wrapping a strap tightly about the neck of the bag (after it has been filled with cash). If the strap can be loosened it may be slid from the neck, cash removed from the bag, and the strap replaced so as to close off the neck without giving any visible evidence that the contents of the bag have been disturbed.

It is an object of the invention to provide a security locking strap which, if tempered with, will give visual indication of such tampering. Another object of the invention is to provide a security locking strap which, once it has been closed tightly, cannot be loosened and re-tightened, and which if removed cannot be used again, at least as a security strap.

Other objects of the invention will become apparent from the following description.

According to the present invention there is provided a locking device including a flexible strap, a housing at one end of said strap, a passage through said housing, the other end of said strap being receivable in said passage when the strap is formed in a loop and said strap being movable longitudi nallythrough said passage to reduce the size of said loop, a locking member attached to said housing in an inoperative position clear of said passage and being movable relative to said housing into an operative position at which it co-operates with a portion of said strap contained within said housing to hold said strap against longitudinal movement relative to said housing, and retaining means preventing return of said locking memberfrom said operative position.

The essential features of the invention, and further optional features, are described in detail in the following passages of the specification which refer to the accompanying drawings. The drawings however, are merely illustrative of how the invention might be put into effect, so that the specific form and arrangement of the features (whetherthey be essential or optional features) shown is not to be understood as limiting on the invention.

In the drawings: Figure 1 is a plan view of a locking device according to one embodiment of the invention.

Figure 2 is a cross-sectional view taken along line ll-ll of Figure 1.

Figure 3 is a cross-sectional view taken along line Ill-Ill of Figure 1.

Figure 4 is an undemeath plan view of the device shown in Figure 1.

Figure 5 is a view of the locking device looped into an operative condition.

Figure 6 is a sectional view through the housing of Figure 5 and taken in the longitudinal direction of the strap.

Figure 7 is a cross-sectional view taken along line VII-VII of Figure 5.

Figure 8 is a view similar to Figure 7 but showing the locking member moved into the operative position.

Figure 9 is a perspective view of the housing end of the locking device in a condition ready for use.

Figure 10 is a view similar two Figure 9 but showing the housing in transverse cross-section.

Figure 11 is a view similar to Figure 10 but showing the strap through the housing and the locking member moved into the operative position.

In the preferred construction as shown in the drawings, the locking device is moulded in a single piece from a suitable plastics material. The device may be made from a flexible tough thermoplastic such as nylon, which is capable of being colour coded if desired.

The locking device includes an elongate flexible strap 1 and a housing 2 formed at one end of the strap 1. The housing 2 has an open ended passage 3 formed therethrough which is shaped and dimensioned to slideably receive the strap 1. That is, the strap 1 can be turned back upon itself to form a loop as shown in Figure 5, and the free end 4 of the strap 1 is able to be passed into and through the passage 3.

It will be seen from Figures 2 and 4 that the housing 2 is essentially in the form of a flat tube, the bore of which forms the passage 3.

As with other devices of this kind, means is provided whereby the strap 1 is held or restrained against withdrawal from a looped condition. In the particular construction shown, the strap 1 is held against withdrawal from the housing 2 by a ratchet mechanism which also functions as indexing means as hereinafter described. For that purpose, the strap 1 has a plurality of holes 5 which are evenly spaced lengthwise of the strap 1 and a ratchet tooth 6 is formed integral with the housing 2 and arranged to locate in each hole 5 as the respective part of the strap 1 is passed thereover.

The tooth 6 has a sloping rear surface 7 which has a ramping effect to lift the strap 1 as it is pulled across the tooth 6. It is therefore possible to reduce the size of the loop by pulling the strap further through the housing 2. The front surface 8 of the tooth 6 however, provides a sharp step which engages against the surface of a hole 5 in which it locates so as to prevent withdrawal of the strap 1 from the passage 3 (Figure 6). In that regard, the top wall 9 of the tubular housing 2 holds the strap 1 against lifting such as to clear the tooth 6 for withdrawal purposes.It is therefore possible to pull the strap 1 through the passage 3 to reduce the loop to the size desired - e.g., to pull tightly around the neck of a cash bag - but movement of the strap 1 in the opposite direction is not possible, or is at least dif The drawing(s) originally filed were informal and the print here reproduced is taken from a later filed formal copy.

ficult.

It is a feature of the device according to the inven tion that a locking member 10 is operable to posi lively lock the strap 1 in a selected position relative to the housing 2. The member 10 is arranged so astro be movable relative to the housing 2 to adopt its operative position and to provide a visible indication that the locking device has been actuated. In the construction particularly shown, the member 10 includes a plate section 11 which is connected to the housing 2 (at least initially) and a peg 12 which is formed integral with the plate section 11 and projects therefrom so as to be adapted for location in a selected strap hole 5.The plate section 11 is dis posed over an opening 13 provided in the top wall 9 ofthe housing 2 (Figures 2 and 7) and that opening 13 is preferably substantially complementary in shape to the peripheral shape of the plate section 11 (Figure 3).

The plate section 11 is preferably formed integral with the housing 2. In the particular construction shown the plate section 11 has a wall 14 provided along each of two opposite sides and the outer edge 15 of each wall 14 is connected to the housing top wall 9 through a thin and frangible connection 16 (Figure 7). As seen in Figures 7 and 8 the peg 12 is located between the side walls 14 and those walls 14 are spaced apart a distance sufficient to receive the strap 1 between them.

When it is desired to operate the locking member 10, pressure is applied to the outer surface of the plate section 11 in the direction shown by arrow 17 in Figure 7. That causes fracture of the connections 16 so the plate section 11 is moved down into the housing opening 13 and atthe same time the peg 12 enters a hole 5 of the strap 1. That hole 5 will be located in alignment with the peg 12 if the strap loop is tensioned so that the following hole 5 is pulled back against the ratchet tooth 6 (Figure 6). The con nections 16 may be broken by hand pressure to the locking member 10 or by pressure applied through the use of a tool such as pliers.

Retaining means is provided to prevent return of the locking member 10 from the operative position as shown in Figure 8. In the construction shown, that retaining means comprises a shoulder 18 on the outside of each side wall 14 of the locking member 10 and which locates beneath the housing top wall 9 as shown in Figure 8. Each shoulder 18 has a sloping under-surface 19 which has a ramping effect during movement of the locking member 10 into the operative position.

As also seen in Figure 8,the peg 12 has an enlarged head 20 which is adapted to snap engage beneath the strap 1 when the peg 12 is fully projected into a hole 5. That is, the head 20 has a diameter silghtly larger than that of the hole 5 whereas the body of the peg 12 is substantially the same diame terorsmallerthanthe hole 5. The head 20 locates within a groove 21 or other recess provided in the lower wall 22 of the housing 2. Snap engagement of the strap 1 and peg 12 further securesthe locking member 10 in the operative position. The locking member cannot be moved out of the operative position in the longitudinal direction ofthe strap 1 because of engagement at one side with the housing top wall 9 and engagement of the peg 12 with the blind end 23 of the groove 21.The blind end 23 of the groove 21 provides support for the peg 12 such as to support it against shearing by tension applied to the strap loop.

The locking device is preferably made of a tough flexible thermoplastic material such as nylon, which ? may be moisture conditioned. This material will provide adequate strength, may be coloured to suit particular requirements, and if required may be embossed to indicate the origin of the bag which is security-locked by means of the device.

In a modification cation of the particular construction shown in the drawings, the strap 1 may extend from the side of the housing 2 opposite to that shown. In another modification, the ledge 24 on the side of the housing 2 opposite the strap 1, may be extended to provide an integral label tag.

When the strap 1 has been wrapped around the neck of a bag, and passed through the passage 3, the locking member 10 can be caused to positively engage with the strap 1 so as to positively lock it in position.

The portion 25 of the strap 1 extending beyond the end 26 of the housing 2 (Figure 5) may be cut off. If the strap 1 is then improperly disengaged from the housing 2 for the purpose of tampering with the contents of the bag, it would be virtually impossible to re-engage the strap 1 in the housing 2 as there would be inadequate strap material to be gripped firmly enough for such engagement to be effected.

The locking device according to the invention has the particular advantage thatthere is a visible change in condition when the locking member 10 has been moved into its operative position. Furthermore, retraction of that member 10 from the operative position can be achieved only with difficulty because the plate section 11 is neatly located within the opening 13 and is flush with housing top wall 9. In addition, the latching engagement between the member 10 and top wall 9 and the peg 12 and strap 1 makes it difficult to withdraw the member 10 from its operative position without causing visible damage and which damage may be such that the member 10 cannot be reused for locking purposes.

It will be noted thatthe locking device of the invention may be moulded simply in a simple two-piece die, which provides for economy in manufacture.

Finally, it is to be understood that various alterations, modifications and/or additions may be introduced into the constructions and arrangements of parts previously described without departing from the spirit of ambit of the invention as defined by the

Claims (11)

appended claims. CLAIMS

1. A locking device including a flexible strap, a housing at one end of said strap, a passage through said housing, the other end of said strap being receivable in said passage when the strap is formed in a loop and said strap being movable longitudinally through said passage to reduce the size of said loop, a locking member attached to said housing in an inoperative position clear of said passage and being movable relative to said housing into an operative position at which it co-operates with a portion of said strap contained within said housing to hold said strap against longitudinal movement relative to said housing, and retaining means preventing return of said locking member from said operative position.

2. A locking device according to claim 1, wherein said locking member is connected to said housing by frangible connecting means, said connecting means being adapted to be broken to permit said locking member to be moved into said operative position, and said locking member co-operates with both said housing and said strap portion in said operative position to hold said strap against longitudinal movement relative to said housing.

3. A locking device according to claim 1 or 2, wherein ratchet means is provided to retain said strap against withdrawal from said housing and which is arranged to permit movement of said strap through said housing to reduce the size of said loop.

4. A locking device according to any preceding claim, wherein said strap has a plurality of apertures therethrough and which are spaced apart in the longitudinal direction of said strap, and said locking member includes a peg which locates within a said aperture when said locking member is in said operative position.

5. A locking device according to claim 4, wherein said peg projects completely through said strap when said locking member is in said operative position.

6. A locking device according to claim 4 or 5, wherein indexing means is provided on said housing and is co-operable with said strap to indicate when a said aperture is located for co-operation with said peg.

7. A locking device according to claim 6, wherein said indexing means includes a ratchet tooth which is formed on said housing and projects into said passage to locate in each said aperture as the respective part of said strap is passed thereacross and engages a surface of the aperture in which it locates to prevent withdrawal of said strap from that position pf engagement, and in that position of said strap another of said apertures is located for coordination with said peg.

8. A locking device according to claim 7 when appended to claim 3, wherein said ratchet tooth and said apertures each forms part of said ratchet means.

9. A locking device according to any one of claims 4 to 8, wherein said retaining means includes an enlarged head at the terminal end of said peg and which is adapted to snap engage beneath the strap when the peg is passed through a said aperture.

10. A locking device according to any preceding claim, wherein said retaining means includes a shoulder on each of two sides of said locking member, each of which is adapted to locate beneath and engage with an opposed surface of said housing.

11. A locking device substantially as herein particularly described with reference to what is shown in the accompanying drawings.