WO2006008442A2

WO2006008442A2 - Security clip

Info

Publication number: WO2006008442A2
Application number: PCT/GB2005/002594
Authority: WO
Inventors: Andrew Searle
Original assignee: Specialist Vehicle Developments Limited
Priority date: 2004-07-23
Filing date: 2005-07-01
Publication date: 2006-01-26
Also published as: WO2006008442A3; GB0416504D0; GB2416562A

Abstract

A security clip is provided for holding a plurality of sheets of material (60, 180), the security clip comprising a body (20) having a first aperture (28) defining a reception region (38) into which at least a portion of the plurality of sheets of material can be inserted via the first aperture, a securing device (50, 120) comprising a securing element (54, 124) moveable between a first position where the securing element permits insertion of sheets of material into the reception region and removal of sheets therefrom and a second position where the securing element co-operates with the body to inhibit removal of one or more sheets from the body, and a tamper evident closure (57, 140) for preventing access to the securing mechanism.

Description

SECURITY CLIP

FIELD OF THE INVENTION

The present invention relates to apparatus for and a method of holding sheets of material such as bank notes together in a secure fashion.

BACKGROUND OF THE INVENTION

Bank notes are routinely transferred to and from banks in large quantities. Typically, during a delivery a security van travels to a point adjacent the bank's premises. A security guard must then carry the bank notes between the security van and the bank. This provides an opportunity for a thief to steal the bank notes from the security guard.

To overcome this problem, the bank notes are stored within a security container whilst being carried by the security guard. The security container includes theft detection means for detecting when a theft is occurring or when the container is being tampered with. If a theft or attempted theft occurs then the theft detection means instructs a spoiling system to dispense spoiling ink onto the bank notes in order to permanently mark the bank notes. The bank notes are then rendered unusable.

Such a system therefore provides a deterrent to thieves from attempting to intercept money during transportation.

It is also desirable to reduce the opportunity for workers in banks or institutions that handle large amounts of money to steal banknotes from a bundle of banknotes. It is known to place bundles of bank notes in sealed tamper evident bags. The bags have to be damaged or destroyed to open them and hence reveal that they have been interfered with. This alerts the users to the fact that the contents of the bag may have changed as a result of unauthorized and/or criminal activity. Unfortunately such sealed bags inhibit the staining of notes by a spoiling means such as an ink delivery system within a security container.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is provided a security clip for holding a plurality of sheets of material, the security clip comprising:

a body having an aperture defining a reception region into which at least a portion of the plurality of sheets of material can be inserted via the aperture;

a securing device comprising a securing element movable between a first position where the securing element permits insertion of sheets of material into the reception region and removal of sheets therefrom and a second position where the securing element co-operates with the body to inhibit removal of one or more sheets from the body; and

a tamper evident closure for preventing access to the securing element.

It is thus possible to provide a security clip whereby sheets of material (such as bank notes) cannot be removed without visibly damaging the security clip or a tamper evident security seal associated therewith. A large portion of the sheets of material remains uncovered by the security clip. Thus the security clip does not present an obstruction to spoiling means for dispensing spoiling ink within a security container.

Preferably the security clip covers and grips one corner or edge of the plurality of sheets of material. Therefore most of the area of the sheets of material remains uncovered by the clip. As a result, spoiling ink from spoiling means has a greater chance of coming into contact with all of the sheets of material and rendering them unusable.

Preferably the securing element co-operates with the body to apply a compressive force to the plurality of sheets of material. Preferably the securing element is adapted to compress the plurality of sheets of material with a camming action. Furthermore with the securing element frictionally inter-engaging with an outermost sheet of the plurality of sheets then an attempt to remove one or more of the sheets results in movement of the outermost sheets and a increase in the compressive force supplied by the securing element.

In a preferred embodiment a user can deliberately induce movement of the securing element after loading the security clip so as to apply a "preload" force to the plurality of sheets such that they frictionally inter-engage with one another and with the body of the security clip and the securing element so as to inhibit removal of one or more of the sheets.

The securing element may be in the form of an eccentric cam positioned opposite a support surface formed in the body. However, in a preferred embodiment the body includes an inclined surface formed within the body and the securing element is arranged to undergo translatory movement with respect to the inclined surface (which will also be referred to as a ramp surface) so as to slide along the inclined surface and become trapped between the inclined surface and the sheets of material, thereby exerting a compressive force on the sheets of material.

Preferably the ramp defines a tapering wall of the reception region such that a first internal dimension of the reception region increases with increasing distance from the aperture and the first internal dimension is perpendicular to the nominal plane of the sheets of material when held by the clip.

Preferably the at least one gripping element comprises a cylindrical member which rolls along the ramp towards the end which is closer to the aperture when a force is applied to the sheets to remove the sheets. The cylindrical member (which may function as a roller) and the sheets are then wedged between the ramp and the body. This causes the plurality of sheets to be gripped harder between the cylindrical member and the body, thus preventing removal of the sheets from the security clip. Alternatively the at least one gripping element may comprise a spherical element, a plurality of cylindrical and/or spherical elements, or any element which would cause further gripping of the sheets when a force is applied to remove the sheets from the security clip.

Preferably the tamper evident closure comprises a tamper-evident security seal which is visibly and irreversibly damaged when a user interferes with the security clip in order to remove the plurality of sheets of material from it. The tamper evident seal may also be used to help locate the securing element. In a first embodiment, the securing element comprises a cylindrical member mounted on a carrier strip and is positioned between the ramp surface and the plurality of sheets of material. The housing may include a second aperture through which the securing element and the carrier strip can be inserted or removed. Alternatively the carrier strip may be inserted into the housing and removed from the housing via the second aperture. Part of the carrier strip may extend through the second aperture such that a user may grasp it and pull on it in order to move the cylindrical member away from the first aperture to release the preload. Part of the carrier strip extends from the housing and is folded back over the housing in order to cover the second aperture. The carrier strip is then fixed to the housing in such a way that access to the second aperture is prevented unless the carrier strip is visibly damaged. A suitable fixing may be a mechanical locking mechanism or may be an adhesive. Therefore it is visibly evident when a user has removed or damaged the carrier strip covering the second aperture in order to remove the securing element from the second position and thus remove the plurality of the sheets of material.

In an alternative embodiment, the carrier strip, when folded back over the housing does not cover the second aperture. Instead, a tamper-evident strip is attached to the end of the carrier strip which is folded over the housing. In order to secure the security clip the tamper-evident strip is fed into a first locking opening in the housing and out of a second locking opening. In this position, the tamper-evident strip covers the second aperture, thereby preventing the removal of the securing element from the second (i.e. securing the bundle of notes) position and the carrier strip. The tamper-evident strip preferably comprises teeth on at least one surface which engage in a ratchet action with the housing. Thus the tamper-evident strip cannot be pulled out of the first locking opening against the ratchet action. To access the second aperture to move the securing element from the second position and in turn remove the plurality of sheets of material, the tamper-evident strip must be cut in order to remove part of the tamper-evident strip through the first and second locking openings, thus exposing the second aperture. This gives a visual indication that the tamper-evident strip has been tampered with.

Preferably, the tamper-evident strip is made from plastic or other flexible material, so that the strip can be easily fed through the first and second locking openings in the housing of the security clip .

Of course, further variations are possible and the ratchet position may be moved such that the strip is folded around the housing before being held in the ratchet.

Preferably the sheets of material comprise bank notes. However the security clip can be used to hold any sheets of material including valuable or sensitive material.

Preferably a spoiling mechanism is provided within the body of the security clip. Alternatively a spoiling mechanism may be attached to the security clip using a tamper evident attachment.

The spoiling mechanism may include a reservoir of a staining agent which is releasable in response to a signal from a controller located within the security clip. The staining agent may be held within a frangible reservoir. The reservoir may be a flexible bag. The reservoir may be under pressure such that formation of a hole in the reservoir causes the spoiling agent to be released into the body of the security clip at a position adjacent the edge of the bundle of bank notes or other items held by the security clip. The reservoir may be opened by an opening means, for example a movable blade or needle. The opening means may be biased to move from a stowed position to an ink release position by a biasing element. The biasing element may be a resilient member or a spring. The opening means may be held in the stowed position by a release mechanism. The release mechanism may comprise a mechanical or electromechanical actuator responsive to the controller.

The controller may be associated with a store of power within the clip. The store of power may be a battery or a capacitor. Alternatively the controller may be arranged to receive the power from an external influence. Thus the controller may comprise or be associated with a coil which may be used to provide power to the release mechanism when in the presence of a varying (for example alternating) magnetic flux or when illuminated by an electromagnetic field such as a suitable radio signal. Advantageously the controller includes processing capability to detect an instruction to cause it to operate the spoiling mechanism. This guards against inadvertent staining of bank notes. As a further alternative the controller may hold the staining mechanism in the non- operative state whilst, and only whilst, the clip is being illuminated by a suitable radio signal or magnetic field. A device may be toggled between these modes in response to a control signal.

Suitable processing capability is commercially available in the form of RF ID tags.

Thus, in the context of a building such as a bank, a transmitter could be placed adjacent the doors of the bank such that an unauthorized attempt to remove cash in the clips from the bank would cause the clips to pass through the electromagnetic field generated by the transmitter and would initiate operation of the spoiling mechanism. The controller may include a delay such that mistakes by authorized users may be corrected by transmitting a suitable "inhibit" code to the controller.

According to a second aspect of the present invention there is provided a security seal for use with the security clip according to the first aspect.

According to a third aspect of the present invention there is provided a method of securing a bundle of bank notes or other planar elements in a clip, the method comprising the steps of: introducing a portion of the bundle into the body of the clip;

moving a securing element from a first position where it permits insertion and removal of the bundle to a second position where the securing element engages with the bundle so as to compress the bundle and thereby hold it securely within the clip; and

placing a tamper evident seal on the clip to inhibit removal of the securing element from the second position.

According to a fourth aspect of the present invention there is provided a security clip arranged to grip a bundle of documents with a compressive force so as to inhibit removal of individual documents from the bundle, the clip further comprising a spoiling mechanism for spoiling the documents in response to an instruction.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be described by way of example only with reference to the accompanying Figures, in which:

Figures Ia and Ib show perspective views of a housing for a security clip constituting a first embodiment of the present invention;

Figure 2 shows a cross-section of the housing of Figure 1;

Figure 3 shows a securing element on a carrier strip for use within the housing of Figures 1 and 2;

Figure 4 shows the housing of Figure 2 with the carrier strip in place;

Figure 5 shows the housing of Figure 4 with a bundle of bank notes inserted therein;

Figure 6 shows the housing with the carrier strip sealed to secure the security clip; Figure 7 shows a cross-section of a housing for a security clip constituting a second embodiment of the present invention;

Figure 8 shows a carrier strip for use with the second embodiment;

Figure 9 shows the housing of Figure 7 with the carrier strip in place;

Figure 10 shows a tamper-evident strip for use with the second embodiment;

Figure 11 shows in detail a reinforced tab constituting part of the carrier strip of Figure 8;

Figure 12 shows a security clip according to the second embodiment with a bundle of bank notes inserted therein and sealed;

Figure 13 shows a bundle of notes with a security clip according to the present invention attached thereto; and

Figure 14 schematically illustrates a security clip with an integral spoiling mechanism.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

The housing 20 of Figure Ia comprises a first portion 22 which in plan view is substantially shaped as a symmetrical trapezium with side walls 23a and 23b being set an angle of substantially 45° to a longitudinal axis of the housing (i.e. 90° with respect to each other), and a second portion 24 which is substantially rectangular. A first end

26 of the first portion 22 is positioned away from the second portion 24 and defines a first aperture 28 at a first end of the housing which, in use, admits a corner of a bundle of bank notes into the housing 20.

The first 22 and second 24 portions of the housing 20 have equal heights and are aligned such that there is a substantially planar surface 30 on one side of the housing 20. An equivalent surface (not shown) on an opposing side of the housing is also substantially planar. The surface 30 includes a rectangular channel 32 which runs from the first end 26 of the first portion 22 to an opposing second end 34 of the housing 20. An identical channel exists in the opposite surface of the housing.

As shown in Figure Ib, the second end 34 of the housing 20 also defines a second aperture 36. The two apertures 28 and 36 define opposing ends of chamber 38 within the housing. The chamber 38 forms a reception region into which a portion, such as a corner, of a stack of sheets of material (e.g. bank notes) can be inserted. The second end 34 is profiled to define a rectangular channel 40, which connects the channel 32 in the face 30 and the corresponding channel (not shown) in the opposite face.

As shown in Figure 2, the vertical cross-section of the internal space 38 along the line A-A of Figure 1 is substantially rectangular inside the second portion 24 of the housing 20. However inside the first portion 22, a first internal surface 42 is arranged at an angle to a second internal surface 44 such that the first surface 42 slopes towards the second surface 44 in the direction of towards the opening 28. The first surface 42 thus defines a ramp or inclined surface relative to the rest of the housing 20.

Figure 3 shows a securing device 50 formed with a securing element in the form of a roller 54 mounted on a carrier strip 52. The carrier strip 52 comprises a flexible strip which may, for example, be formed of paper or a flexible plastics. The roller 54 is fixed to or carried on the strip 52 and comprises two halves of a cylinder fixed across the width of opposing surfaces of the carrier strip 52. In this embodiment the roller does not in fact roll, but instead slides along the inclined surface 42 as explained below. The roller 54 is closer to one end 56 of the carrier 52, thus defining a longer carrier strip portion 57 and a shorter carrier strip portion 58 with the roller 54 therebetween.

Before use, the securing device 50 is inserted into the housing 20 through the first aperture 28 or through the second aperture 36 as shown in Figure 4, with the longer strip 57 portion extending from the first aperture 28 in the first end 26. The securing device 50 is positioned such that the roller 54 is in the vicinity of the ramp defined by first surface 42 within housing 20. In this position, a significant portion of the longer strip 57 extends out of the first aperture 28, and a small amount of the shorter strip 58 extends out of the opening 36.

In order to grip a bundle 60 of bank notes securely, a corner of the bundle is inserted through the first aperture 28 when the securing device 50 is in the position shown in Figure 4. The bundle is inserted such that the longer strip 57 is situated between the incclined surface 42 and the bundle 60. This is shown in Figure 5. The bundle 60 is inserted until the edges of the bundle engage with the walls 23a and 23b (Figure 1) resulting in a corner 62 of the bundle being adjacent the second opening 36.

Next, the security clip is securely sealed using the longer strip 57. The longer strip 57 is pulled taut so as to cause the roller 54 to become trapped between the bundle 60 of the bank notes and the inclined surface 42. The strip 57 is then wrapped around the housing such that it lies within the channels 32 and 40, and the further channel (not shown) situated in the surface opposite to the surface 30. The longer strip 57 is shown wrapped around the housing 20 in Figure 6. The wrapping action causes the roller 54 to be pulled towards the opening 28 such that it is wedged between the ramp surface 42 and the bundle 60. This in turn causes the bundle 60 to be compressed between the roller 54 and a lower portion 70 of the housing 20. Thus the bundle 60 will not fall out of the security clip. The wrapping action also causes the end of the shorter strip 58 to be folded towards the housing 20. The longer strip 57 also covers the opening 36 in the housing 20.

The longer strip 57 is then fixed to the housing 20 in an end region 72 of the longer strip 57 using adhesive. This secures the security clip as access to the roller 54 is impossible without breaking the longer strip 57 or the housing 20. Thus the security clip has a tamper-evident seal, and the longer strip 57 forms a tamper evident closure for the second aperture 36, preventing access to the roller 54 or the shorter strip 58. The adhesive may be carried on the strip 57 and be a contact adhesive. The roller 54 in this example is not rotatably fixed to the carrier strip 50, so does not actually rotate or "roll" with respect to the carrier, strip but can undergo a limited rolling action if an attempt is made to pull the bundle out of the security clip.

When a force is applied to the bundle 60 in a direction shown by the arrow 74 to remove the bundle from the housing 20, the bundle 60 drags the roller 54 further along the ramp surface 42 towards the opening 28 as the bundle is pulled out of the opening 28. As a result the bundle 60 is wedged more firmly between the roller 54 and the lower portion 70 of the housing 20, and removal of the bundle 60 is thus prevented.

In order to remove the bundle 60, a user breaks the longer strip 57 in order to access the second aperture 36. The user then pulls the shorter strip 58 which pulls the roller 54 away from the ramp surface 42. The roller 54 then no longer grips the bundle 60, and the bundle 60 can be freely removed.

In an alternative embodiment, the security clip includes a housing 100 as shown in the cross-section in Figure 7 in place of the housing 20. The housing 100 is identical to the housing 20 except that there is no opening 36 in the end 34. Instead there is an opening 102 in the surface 30 which allows access to the interior space 38. There is also a first locking opening 104 in the surface 30, and a second locking opening 106 positioned substantially at the position of the opening 36 in the housing 20 of Figure 1. A channel 108 links the first and second openings 104 and 106, and is bounded by a portion 107 of the housing.

A securing device 120 as shown in Figure 8 is contained permanently within the housing 100. The securing device 120 comprises a carrier strip of flexible material 122 with a cylindrical roller 124 mounted thereon. The carrier strip 122 also comprises a reinforced tab 126 mounted at one end thereof with openings 128 through the reinforced tab 126. The reinforced tab 126 and the strip portion leading to the tab 126 are of reduced width relative to the strip in the region of the roller 124. At the opposite end of the strip there is a release tab 129 also of slightly reduced width. The roller 124 is held on the carrier strip 122 such that it can rotate. An opening 130 in the carrier strip 122 ensures that the roller 124 projects from both sides of the carrier strip 122. Ends 132 of the roller 124 each include an axial extension 134 of reduced radius which is held between the carrier strip 122 and a further small strip 136. The strip 136 is formed by making a slot in the material of the carrier strip such that the extensions of the roller can be held within the slit. Thus the roller 124 can rotate about an axis which is transverse to the longitudinal axis of the carrier strip 122.

As shown in Figure 9, the roller 124 is contained within the housing 100 in the internal space 38 substantially in the region of the ramp surface 42. The carrier strip 122 extends out of the opening 28 and terminates in the reinforced tab 126. The release tab 129 extends out of the opening 102.

In order to clip a bundle of notes 60 within a security clip which includes the housing 100 and securing device 120 as shown in Figure 9, a corner 62 of the bundle 60 is inserted into the opening 28 such that the carrier strip 122 is positioned between the ramp surface 42 and the bundle 60. The bundle 60 is inserted until the corner 62 hits the rear wall 64 and/or the sides of the bundle abut walls 23a and 23b.

In order to secure the security clip so that it is tamper evident, a tamper-evident strip 140 as shown in Figure 10, which is typically formed of plastics, is fixed to the carrier strip 122. The tamper evident strip 140 comprises a main body 142 which is smooth on one side, and on the opposite side has a saw-tooth profile 144 having teeth parallel to the width of the strip 140. The strip 140 also includes a clip portion 146 which can be releasably attached to the reinforced tab 126 of the carrier strip 122. The clip portion 146 includes two thin studs 147 which have enlarged heads.

The clip portion 146 is attached to the body 142 of the tamper-evident strip 140 by a plurality, in this example three, thin strands 148.

Figure 11 shows the openings 128 in the reinforced tab 126 of the carrier strip 122 in detail. Each opening 128 comprises a large opening 150 co-operating with an adjacent smaller opening 152. The large opening 150 is large enough to admit the enlarged heads of the studs 147. The smaller opening 152 can admit the thin studs 147 but not the enlarged heads. Thus the clip portion 146 can be releasably attached to the reinforced tab 126 by inserting the enlarged heads fully through the large openings 150 and then moving the studs into the smaller openings 152.

In order to seal the security clip, the tamper-evident strip 140 is attached to the carrier strip 122 via the clip portion 146 and reinforced tab 126. The main body 142 of the strip 140 is then inserted through the opening 104 in the housing 100, and out of the opening 106 (Figure 7). The main body 142 is pulled through the openings 104 and 106 until the tamper-evident strip 140 and carrier strip 122 become taut, as shown in Figure 12. This results in the roller 124 being wedged between the ramp surface 42 and the bundle 60, thus gripping the bundle 60 between the roller 42 and a lower portion 70 of the housing 100.

Once the strips 122 and 140 have been pulled taut, the clip portion 146 and reinforced tab 126 cannot be separated. This is achieved by ensuring that the smaller openings 152 in the openings 128 in the reinforced tab 126 are situated towards the direction in which the body 142 of the tamper-evident strip 140 is pulled. Thus the thin studs 147 are held within the smaller openings 152 and cannot be removed due to the enlarged heads. Because the strips are taut, the studs 147 cannot be moved to the larger openings 150.

The teeth 144 grip on the portion 107 of the housing, thereby preventing the strip 140 from being removed. In order to open the clip to release the notes from the bundle the strands 148 of the tamper evident strip 140 have to be severed.

In order to remove the bundle 60, a user must gain access to the release tab 129 of the securing device 120. The release tab protrudes slightly from the opening 102 in the housing 100. When the user pulls the release tab 129 out of the opening 102, the roller 124 moves along the ramp surface 42 such that the bundle 60 is no longer gripped within the housing 100. As noted before, in order to access the release tab 129, the user must cut the longer strip 122 of the roller strip 120, the thin strands 148 of the tamper-evident strip 140, or the main body 142. Alternatively the user breaks the studs 147. In any case it is visibly evident that the housing 60 has been tampered with. Preferably, when an authorized user wishes to remove the bundle 60, the thin strands 148 are cut.

The main body 142 of the tamper-evident strip 140 is then fed through the openings 104 and 106 and removed. The release tab 129 is thus exposed, and is pulled to release the bundle 60. Once the bundle 60 has been removed, the clip portion 146 of the tamper- evident strip 140 can be easily removed from the reinforced tab 126 of the roller strip 120, by feeding the studs 147 through the larger openings 150 in the reinforced tab 126. A further tamper-evident strip can then be attached to the reinforced tab 126 when the security clip is re-used to clip another bundle of bank notes.

The securing devices shown in Figure 3 and 8 may be fitted with a roller 54 or 124 which can or cannot roll as appropriate, so that the embodiments described are not limited to a certain type off roller. Other roller implementations are also possible.

A bundle of bank notes 60 is shown in Figure 13 gripped by a security clip 160 according to the first or second embodiment of the present invention. It can be seen that the majority of the bundle of notes 60 is uncovered by the security clip 160. The present invention therefore allows the bundle 60 to be gripped in a secure tamper- evident fashion, and does not present an obstruction to a spoiling system inside a security container. Thus spoiling ink dispensed by such a system can reach all of the notes in the bundle without the need for puncturing devices.

Figure 14 schematically shows the internal configuration of a clip having an integral spoiling system. The tamper evident closure encircling this clip can be of the types described hereinbefore. However the clip shown in Figure 14 further includes an antenna 170 connected to an RF ID tag 172 which functions as a controller. The controller 172 is connected to a electromechanical actuator 174 forming opening means which is arranged to rupture a flexible reservoir of ink 176 which is located adjacent the bundle of notes 180 designated by the chain line. Integral moldings 182 within the clip direct the ink from the reservoir 176 after it has been ruptured towards the edge of the bundle of notes. When the clip is illuminated by a suitable electromagnetic field, the antenna receives sufficient energy to power up the RF ID tag and to enable it to perform its internal processing. The clip may include a capacitor 184, or indeed a battery, which acts as a store of sufficient energy to operate the actuator 174 to puncture the reservoir 176. The RF ID tag 172 can control the supply of energy to the capacitor 184 in order to ensure that sufficient charge is stored on the capacitor to operate the actuator. Users of such a clip might routinely arrange for the clip to be illuminated by a suitable electromagnetic field in order to ensure that the capacitor 184 is maintained in a state of charge sufficient to cause actuation of the actuator 174. The RF ID tag includes internal memory and processing capability and hence it can be arranged to operate the actuator only in response to a suitable coded signal. Therefore inadvertent operation of the spoiling system can be avoided. The tag may also be arranged to implement a time delay, thereby giving users the opportunity to issue an inhibit signal if, by accident, they have accidentally passed the clip and its contents through a radio field, for example due to a transmitter positioned at the door of a bank, which transmits the spoiling system actuation signal.

Only a small volume of ink is required to spoil the notes because the ink reservoir is held in intimate contact with the edge of the bundle 180. It is thus possible to provide a security device which inhibits theft from the bundle both by external threats and by the action of the companies own employees.

Claims

1. A security clip for holding a plurality of sheets of material (60, 180), the security clip characterised by comprising: a body (20) having a first aperture (28) defining a reception region (38) into which at least a portion of the plurality of sheets of material can be inserted via the first aperture; a securing device comprising a securing element (54, 124) movable between a first position where the securing element permits insertion of sheets

(60) of material into the reception region and removal of sheets therefrom and a second position where the securing element co-operates with the body to inhibit removal of one or more sheets from the body; and a tamper evident closure (57, 140) for preventing access to the securing element.

2. A security clip as claimed in claim 1, wherein the securing element (54, 124) co- operates with the body (20) to apply a compressive force to the plurality of sheets of material (60, 180).

3. A security clip as claimed in claim 1 or 2, wherein the securing element (54, 124) is adapted to compress the plurality of sheets of material (60, 180) with a camming action.

4. A security clip as claimed in claim 1, 2 or 3, wherein the securing element (54, 124) is movable after the at least a portion of the plurality of sheets of material (60, 180) have been inserted into the security clip so as to apply a preload force to the plurality of sheets such that they frictionally inter-engage with one another and with the body (20) of the security clip and the securing element so as to inhibit removal of one or more of the sheets.

5. A security clip as claimed in claim 3 or 4, wherein the securing element (54, 124) comprises an eccentric cam positioned adjacent a support surface formed in the body.

6. A security clip as claimed in claim any of the preceding claims, wherein the body (20) includes an inclined surface (42) formed within the body and the securing element is arranged to undergo translatory movement with respect to the inclined surface so as to become trapped between the inclined surface and the sheets of material (60, 180), thereby exerting a compressive force on the sheets of material.

7. A security clip as claimed in claim 6, wherein the inclined surface (42) defines a tapering wall of the reception region such that a first internal dimension of the reception region increases with increasing distance from the first aperture (28) and the first internal dimension is generally perpendicular to a nominal plane of the sheets of material (60, 180).

8. A security clip as claimed in claim 6 or 7, wherein the securing element (54, 124) comprises a cylindrical member arranged to roll or translate along the inclined surface (42) towards the first aperture (28) when a force is applied to the sheets (60, 180) to remove the sheets.

9. A security clip as claimed in any preceding claim, wherein the securing element (54, 124) is mounted on a carrier strip (52, 122).

10. A security clip as claimed in claim 9, wherein a first part (58, 129) of the carrier strip (52, 122) is adapted to extend through a second aperture (36, 102) in the body.

11. A security clip as claimed in claim 10, wherein a second part (57) of the carrier strip (52, 122) is arranged to form the tamper evident closure by extending from the first aperture (28) and being folded back over the housing (20) in order to cover the second aperture (36, 102) such that access to the second aperture is prevented unless the carrier strip is visibly damaged.

12. A security clip as claimed in claim 10 or 11, wherein the second part of the carrier strip (122) is attachable to the tamper evident closure in the form of a tamper-evident strip (140), and in order to secure the security clip the tamper- evident strip is fed into a first locking opening (104) in the body and out of a second locking opening (106) in the body.

13. A security clip as claimed in claim 12, wherein the tamper-evident strip (140) comprises teeth (144) on at least one surface which are engageable with a ratchet within the body such that the tamper-evident strip cannot be fed into the second locking opening (106) and out of the first locking opening (104).

14. A security clip as claimed in any preceding claim, wherein a spoiling mechanism is provided within the body of the security clip, or is attachable to an attachment on the security clip.

15. A security clip as claimed in claim 14, wherein the spoiling mechanism includes a reservoir (176) of staining agent which is releasable in response to a signal from a controller (172) located within the clip.

16. A security clip as claimed in claim 15, wherein an opening means (174) for releasing staining agent from the reservoir comprises a movable blade or needle arranged to be moved from a stowed position to an ink release position by a biasing element.

17. A security clip as claimed in any of claims 15 to 16, wherein the controller (172) is associated with a store of power (184) within the clip, or is arranged to receive the power from an external influence.

18. A security clip as claimed in claim 15, wherein the controller (172) comprises or is associated with a coil which may be used to provide power to the spoiling mechanism when in the presence of a varying magnetic flux or when illuminated by an electromagnetic field.

19. A security clip as claimed in any of claims 15 to 18, wherein the controller (172) is responsive to an instruction to cause it to operate the spoiling mechanism.

20. A security seal for use with the security clip according to any preceding claim.

21. A method of securing a bundle of sheets of material (60, 180) in a clip, the method comprising the steps of: introducing a portion of the bundle into the body (20) of the clip via a first aperture (28); moving a securing element (54, 124) from a first position where it permits insertion and removal of the bundle to a second position where the securing element engages with the bundle so as to compress the bundle and thereby hold it securely within the clip; and placing a tamper-evident seal (57, 140) on the clip to inhibit removal of the securing element from the second position.

22. A method as claimed in claim 21, wherein the step of moving the securing element (54, 124) comprises translating the securing element with respect to an inclined surface (42) within the body (20) of the clip to trap the securing element between an internal inclined surface and the bundle of sheets of material (60, 180), thereby exerting a compressive force on the sheets of material.

23. A method as claimed in claim 21 or 22, wherein the securing element (54) is mounted on a carrier strip (52) and is accessible through a second aperture (36) in the body, and the step of placing a tamper evident seal on the clip comprises folding a part (57) of the carrier strip which extends from the first aperture (28) back over the housing to cover the second aperture (36) such that access to the second aperture is prevented unless the carrier strip is visibly damaged.

24. A security clip arranged to grip a bundle of documents (60, 180) with a compressive force so as to inhibit removal of individual documents from the bundle, the clip further comprising a spoiling mechanism for spoiling the documents with a staining agent in response to an instruction.