Closure for a shipping bag

Abstract

A closure for a shipping bag having an opening. The closure comprises a blocking element movable between a first position in which access to the opening of the shipping bag is blocked and a second pos

Description

Technical Field

[0001] The present disclosure relates to a closure for a shipping bag, and a shipping bag including the closure. Background

[0002] Closures for shipping bags are typically single-use adhesive strips or plastic seals, applied to a flap which forms an integral part of a back panel of the shipping bag and folds over a front panel of the shipping bag to close an opening of the shipping. These solutions are secure and provide a form of tamper evidence. However, for environmental reasons, it would be desirable to further reduce the use of non-biodegradable materials to allow the shipping bags to be reused as much as possible. It would also be desirable to further improve the tamper evidence of shipping bags, so it can be easily detected when a shipping bag has been opened or tampered with.

[0003] It is an aim of the present invention to address one or more of the disadvantages associated with the prior art. Summary of Invention

[0004] Aspects and embodiments of the invention provide a closure for a shipping bag and a shipping bag as claimed in the appended claims.

[0005] According to an aspect of the present invention there is provided a closure for a shipping bag having an opening. The closure comprises a blocking element movable between a first position in which access to the opening of the shipping bag is blocked and a second position in which access to the opening of the shipping bag is permitted. The closure further comprises a clip configured to be located over the opening of the shipping bag, wherein the clip comprises a first wing and a second wing configured to respectively engage first and second faces of the shipping bag. The clip includes a receiving portion in the form of a loop projecting from the first wing and configured to extend through a cut-out in the second wing to receive the blocking element, and a catch arrangement defined in the second wing and configured to be engaged by the blocking element. In the first position, the blocking element is received in the receiving portion and engages the catch arrangement. The blocking element is configured to break under application of a predetermined force to disengage from the catch arrangement and enable the blocking element to be moved from the first position to the second position such that the blocking element is removed from the receiving portion and access to the opening of the shipping bag is permitted.

[0006] As the blocking element blocks access to the opening of the shipping bag when it is located in the receiving portion and engages the catch arrangement, the contents of the shipping bag are protected. When a user wishes to open the shipping bag, they can apply a force to move the blocking element and disengage it from the catch arrangement and remove it from the receiving portion. As the blocking element can only be disengaged from the catch arrangement by being broken, the closure acts as a tamperproof arrangement, indicating if the shipping bag has been opened before being received by the user.

[0007] The engagement of the first and second wings with the first and second faces of the shipping bag, respectively, may serve to hold together the faces of the shipping bag. In such arrangements, the blocking element may act to block disengagement of the wings with the faces of the shipping bag, preventing the faces of the shipping bag from being separated to permit access to the opening.

[0008] The blocking element may be configured to be moved in a first direction to engage the catch arrangement and configured to be moved in a second direction opposite to the first direction to disengage from the catch arrangement.

[0009] Assembly of the closure is simple as the blocking element simply needs to be inserted in a first direction to engage the catch arrangement. A user can then simply move it in the opposite second direction to break the blocking element and disengage it from the catch arrangement so the shipping bag can be opened.

[0010] The catch arrangement may comprise an engaging edge configured to be engaged by the blocking element in the first position to impede movement of the blocking element in the second direction.

[0011] As the blocking element engages the engaging edge of the catch arrangement, the blocking element cannot be easily disengaged from the catch arrangement without the blocking element being broken.

[0012] The blocking element may comprise an end portion that is folded over in the first position and the end portion abuts the engaging edge of the catch arrangement.

[0013] The folded over end portion retains the blocking element in the catch arrangement without any additional components or fixing arrangement being required. As the end portion of the blocking element abuts the engaging edge of the catch arrangement, the blocking element is retained by the catch arrangement. The blocking element must be broken by the at least part of the end portion being separated from the remainder of the blocking element so that the blocking element can be removed from the catch arrangement and receiving portion.

[0014] The catch arrangement may comprise a contact surface and an opening, such that during assembly of the closure the blocking element can be inserted into the catch arrangement through the opening of the catch arrangement. The end portion of the blocking element may be guided in the first direction along the contact surface such that the end portion engages the engaging edge of the catch arrangement.

[0015] The contact surface directs the blocking element in the first direction during assembly of the closure such that the end portion of the blocking element locates correctly, and the end portion engages the engaging edge to retain the blocking element in the catch arrangement.

[0016] The end portion of the blocking element may comprise an abutting edge, and the abutting edge of the end portion of the blocking element may engage the engaging edge of the catch arrangement.

[0017] As the end portion is sandwiched by the layers of the catch arrangement, the frictional engagement, and there being no space for the end portion to unfold again, retains the blocking element in the first position. The blocking element can only be removed by a sufficient force being applied that the end portion breaks away from the remainder of the blocking element.

[0018] The contact surface may be defined by a catch layer that has been folded about a fold line and fixed to a reinforcing layer. The fold line may be defined at an end of the catch layer opposite the engaging edge of the catch layer.

[0019] The catch layer may include a recessed portion that defines the engaging edge. The recessed portion may help to ensure an extra level of tamper-proofing of the catch arrangement.

[0020] As the catch layer is folded over about the fold line to locate substantially parallel to the reinforcing layer, the engaging edge faces the first direction. The end portion of the blocking element slides along the contact surface and engages the engaging edge of the catch layer.

[0021] The catch arrangement may further comprise a flap portion configured to guide the blocking element into the opening of the catch arrangement.

[0022] The guiding of the flap portion aids assembly of the closure. Frictional engagement of the flap portion of the catch arrangement and the blocking element also helps to retain the blocking element in the first position.

[0023] The blocking element may comprise a weakened portion configured to be broken when the predetermined force is applied to the blocking element.

[0024] The weakened portion helps to ensure a consistent breaking mechanism of the blocking element when it is desired to move to the second position.

[0025] The weakened portion may comprise a stress riser feature configured to concentrate stress in a failure zone of the weakened portion to break the blocking element at the failure zone when the predetermined force is applied to the blocking element.

[0026] The term "failure zone" denotes a region that has been predisposed and designed to separate in response to the application of the predetermined force. In other words, the failure zone provides the weakened portion of the blocking element resulting in a localisation of applied stress that ultimately tears or ruptures the blocking element along or near the failure zone. The tearing or rupture of the blocking element in the failure zone provides a clear visual clue that the shipping bag has been opened to discourage interference with packaged items.

[0027] The stress riser feature may comprise a cut line bridging first and second parts of the fold line defining the end portion of the blocking element.

[0028] The cut line acts as the stress riser by concentrating stress. The material at the end portion therefore cannot distribute the load as effectively as the rest of the material, leading to a higher stress concentration at the first and second parts of the fold line. In terms of fracture mechanics, the presence of a cut line lowers the amount of energy required for a crack or tear to propagate. It will also be appreciated that other means for creating a stress riser are conceivable, for example a relatively deep continuous score caused by a creasing tool, or a sharp angle or bend in the blocking element that will concentrate a force.

[0029] The end portion of the blocking element may be folded over about the first and second parts of the fold line such that the cut line defines a tip portion extending in the first direction from the first and second parts of the fold line.

[0030] When the end portion of the blocking element is folded and the blocking element is in the first position, the tip portion is arranged to contact a layer of the closure such that when it is moved in the second direction, the tip portion will catch on the closure material and a tear will start to propagate. The cut line is configured such that the adjacent material is subject to Mode III (out-of-plane shear) loading conditions. Under these conditions, when the blocking element is moved in the second direction, the material on either side of the tip portion experiences shear forces that act perpendicular to the plane of the cut. This configuration facilitates a controlled tear, with the material tearing from the tip portion in a predictable manner, separating at least part of the end portion from the remainder of the blocking element and allowing the blocking element to disengage from the catch arrangement.

[0031] The cut line may be a continuous line of uniform curvature. Such a geometry inherently facilitates a predictable tear path due to the consistent rate of change in direction along the curve. In essence, the tear initiated at the cut line is constrained by the curved boundary on either side. As a tear tends to propagate in a direction perpendicular to the highest tensile stress, the uniform curvature creates a steady stress gradient that guides the tear along the path of the curve. The cut line may define a semi-circle.

[0032] The loop may be moveable between flat and erected conditions. The loop may be configured to extend through the second wing in the erected condition.

[0033] Advantageously, if the loop can be formed in a flat condition, manufacture of the closure is aided as it can be passed down a line of an automated gluer machine before the loop is then erected as part of the assembly process. The first wing can have an aperture leading to a pushable surface such that when pressure is applied to the pushable surface by the user, the loop is erected. The loop can have at least one projection configured to engage an edge of the cut out in the second wing to help hold the first and second wings together.

[0034] The second wing may be defined by a first panel connected to a second panel with a fold line. The first panel may be configured to overlie and be fixed to the second panel. The first panel may comprise the catch layer that includes the engaging edge and the reinforcing layer.

[0035] As the first panel is configured to overlie and be fixed to the second panel, the opening of the catch arrangement locates adjacent the contact surface such that the blocking element engages and slides along the contact surface towards the engaging edge when the blocking element is inserted into the opening of the catch arrangement during assembly of the closure. Advantageously, the catch arrangement cannot be easily accessed, so the blocking element cannot be easily manipulated to bypass the tamperproof mechanism. Such an arrangement also simplifies the manufacturing process as the catch arrangement can be formed in the first and second wings rather than as a separate component.

[0036] The first panel of the second wing may comprise a recess. The second panel of the second wing may comprise a recess. The recess of the first panel may be configured to align with the recess of the second panel. The recess of the first panel and the recess of the second panel may be configured to align with the loop projecting from the first wing when the second wing overlies the first wing such that the loop extends through the cut-out in the second wing.

[0037] As the loop is fixed relative to the first face of the shipping bag and the cut-out is fixed to the second face of the shipping bag, when the blocking element is received in the loop, the first and second faces of the shipping bag cannot be separated. At least the second face of the shipping bag may also comprises a corresponding cut-out so the loop can extend through the second face of the shipping bag and the blocking element be passed through during assembly.

[0038] The blocking element may comprise an elongated strip portion.

[0039] The elongate strip portion shape aids the user in threading the blocking element through the receiving portion to engage the catch arrangement.

[0040] The blocking element may further comprise an enlarged head portion at an end of the blocking element opposite where the blocking element engages the catch arrangement. The head portion may be configured to be engaged by a user to pull the strip portion towards the second position.

[0041] In the first position, the enlarged head may be configured to abut against the receiving portion to inhibit movement of the blocking element within the receiving portion in a first direction beyond the enlarged head portion. This inhibits the blocking element from being moved into an alternative position where access to the opening is permitted by moving the blocking element in the first direction.

[0042] The blocking element may be a first blocking element, and the closure may further comprises a second blocking element arranged to be stored in the shipping bag such that the shipping bag can be re-closed once the first blocking element is broken.

[0043] Advantageously, if the user wishes to re-close the shipping bag, for example to return goods, they can use the second blocking element to securely re-close the shipping bag before it is sent back. The end portion of the second blocking element may be folded over by the user based on instructions or may be pre-folded during the manufacturing process and provided in this condition.

[0044] The blocking element may comprise a directional indicator pointing in the first direction or second direction, to indicate to the user how to open or re-close the shipping bag.

[0045] This could be an arrow or similar, to improve the user experience.

[0046] The closure may be formed from a paper-based material. Optionally, the closure may be formed from card or paperboard. Optionally, the closure may be formed from fluted paperboard. Fluted paperboard advantageously has sufficient strength to provide a reliable tamper proof arrangement.

[0047] In a further aspect of the invention, a shipping bag is provided having first and second faces: The shipping bag includes the closure of the previous aspect, wherein the first wing of the closure engages the first face of the shipping bag and the second wing of the closure engages the second wing of the shipping bag.

[0048] Within the scope of this application, it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and / or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and / or features of any embodiment can be combined in any way and / or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim, or file any new claim, accordingly, including the right to amend any originally filed claim to depend from and / or incorporate any feature of any other claim although not originally claimed in that manner. Brief Description of Drawings

[0049] One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0050] Figure 1 is a plan view of an internal surface of a blank for forming a closure for a shipping bag according to an embodiment of the invention;

[0051] Figure 2 is a plan view of a blocking element to be supplied to a user as part of the closure for the shipping bag;

[0052] Figure 3 is a plan view of an auxiliary blocking element which is supplied to the user separately from the pre-assembled closure for re-closing the shipping bag;

[0053] Figure 4 is a fragmentary plan view of an external surface of a blank for forming the shipping bag that locates the closure;

[0054] Figures 5 to 10 are perspective views illustrating successive steps of assembling the closure on the shipping bag to close the shipping bag in a tamper-evident manner;

[0055] Figures 11 and 12 are perspective views illustrating successive steps of releasing the engaged closure from the shipping bag; and

[0056] Figure 13 is a perspective view of a blocking element following release of the closure. Detailed Description

[0057] Referring to the drawings, and firstly looking at Figure 10, a shipping bag 10 with a closure 34 is shown. The closure 34 is for closing an opening 12 of the shipping bag. As will be described in more detail below, in this embodiment, the closure 34 includes a blocking element 78 movable between a first position in which access to the opening of the shipping bag is blocked and a second position in which access to the opening of the shipping bag is permitted. The closure 34 also includes a receiving portion configured to receive the blocking element. In this embodiment, the receiving portion is a loop 50. The closure 34 also includes a catch arrangement 66 configured to be engaged by the blocking element 78. The catch arrangement 66 is configured to be engaged by the blocking element 78 in the first position to impede movement of the blocking element 78. As will be described in more detail below, the blocking element 78 is configured to break under application of a predetermined force to disengage from the catch arrangement 66 and enable the blocking element 78 to be moved from the first position to the second position such that the blocking element 78 is removed from the loop 50 and the opening of the shipping bag can be accessed.

[0058] In this embodiment, the components of the closure 34 are formed from a paperbased material such as card or paperboard. Optionally, the components of the closure 34 are formed from fluted paperboard. Fluted paperboard advantageously has sufficient strength to provide a reliable tamper proof arrangement. As the whole closure 34 is formed from a paper-based material, it is recyclable.

[0059] As can be seen more clearly in Figure 12, the contents of the shipping bag 10 can be inserted and removed through the opening 12. In this embodiment, the shipping bag 10 has a front face 14 opposing a back face 16. Extending between the front face 14 and the back face 16 are a first side 18 and a second side 24. As shown in Figure 4, the bag is formed from a blank 11. At an upper end of the bag 10, the second side 24 has first and second panels 20, 22. The first side 18 has first and second panels 26, 28. At the top of the bag 10, the front face 14 has an upper front panel 15. At the top of the bag 10, tThe rear face 16 has an upper rear panel 17. The bag 10 is assembled by connecting the front face 16 to the first side 18 with vertically extending glue line Gl. The front panel 15 and rear panel 17 each have a single recess 19 in this embodiment. It will be appreciated, however, that in other embodiments the front panel 15 and the rear panel 17 may each included multiple recesses 19, as required.

[0060] In this embodiment, when the bag 10 is assembled, the first and second panels 20, 22 of the first side 18 and the first and second panels 26, 28 of the second side 24 are folded such that they extend at an angle relative to the front face 14 and back face 16 to define the opening 12, which is substantially hexagonal in shape. In this embodiment, the front face 14, back face 16, first side 18 and second side 24 extend vertically downwards such that a base (not shown) of the bag 10 is substantially the same shape as the opening. In alternative embodiments (not shown), the first and second panels 20, 22 of the first side 18 and first and second panels 26, 28 of the second side 24 extend substantially perpendicular to the front face 14 and back face 16 to define a substantially rectangular opening 12. In other alternative embodiments, the base is a different shape to the opening to define a bag that tapers outwardly or inwardly towards the base.

[0061] Looking at Figures 10 and 11, when the shipping bag 10 is closed, the first and second panels 20, 22 of the first side 18 are folded so they overlie one another. The first and second panels 26, 28 of the second side 24 are folded so they overlie one. In this embodiment, at the top of the bag 10, the first side 18 and the second side 24 extend substantially parallel to the front face 14 and the back face 16. An internal surface of the front face 14 engages an internal surface of the back face 16 such that the opening 12 is closed. Together, the first panel 20 of the first side 18, the first panel 26 of the second side 24, and the front face 14 define a first engaging surface of the bag 10 in the form of a front fringe 30. Together, the second panel 22 of the first side 18, the second panel 28 of the second side 24, and the rear face 16 define a second engaging surface of the bag 10 in the form of a rear fringe 32. The front fringe 30 and the rear fringe 32 are indicated in Figure 4 on the blank 11 of the bag 10.

[0062] As described in more detail below, the closure 34 engages the first and second engaging surfaces of the bag 10 to keep the opening 12 closed. In this embodiment, more specifically, a clip 36 of the closure 34 locates on the bag 10 and engages the front and rear fringes 30, 32 to keep the opening 12 closed.

[0063] Figure 1 shows a blank 37 for the clip 36. The clip 36 is configured to be located over the opening of the bag 10, and so the clip 36 has a first clip wing and a second clip wing configured to respectively engage first and second faces of the bag 10. In this embodiment, the first clip wing is a rear wing 38 and the second clip wing is a front wing 40, shown in Figure 1 and Figure 12. The front wing 40 is arranged to engage the front fringe 30 of the bag 10. The rear wing 38 is arranged to engage the rear fringe 32 of the bag 10. The engagement of the front and rear wings 40, 38 of the clip 36 with the front and rear fringes 30, 32 of the bag 10, respectively, may serve to hold together the front panel 15 of the front face 14 and the rear panel 17 of the rear face 16 of the bag 10. Also, the first and second panels 20, 22 of the first side 18 are held together, as well as the first and second panels 26, 28 of the second side 24. Therefore, the opening of the bag 10 is closed by the clip 36 when it is located on the top of the bag 10.

[0064] The blank 41 shown in Figure 1 indicates an internal surface once the blank 41 is assembled, as described in more detail below. A central axis A-A defines a longitudinal direction of the blank 41. Perpendicular to the axis A-A defines a transverse direction. In this embodiment, the blank of the clip 36 extends along the axis A-A to have a length that is substantially equal to the width of the shipping bag it will be fixed to. This helps to ensure that the goods within the shipping bag cannot be accessed when the clip 36 is located on the bag 10.

[0065] The front wing 40 is defined by a first panel 42 and a second panel 44, divided by a longitudinally extending fold line LI. The rear wing 38 is defined by a first panel 46 and a second panel 48, divided by a longitudinally extending fold line L2. Between the second panel 44 of the front wing 40 and the first panel 46 of the rear wing 38 are two longitudinally extending fold lines L3. In this embodiment, there are two fold lines L3 spaced from one another a sufficient amount to account for the thickness of the front and rear wings 40, 38 when they are folded over (described in more detail below) as well as the thickness of the bag 10 when the clip 36 is located on the bag 10. In other embodiments, there may be more or fewer fold lines as required. In this embodiment, the first and second panels 42, 44 of the front wing 40 and the first and second panels 46, 48 of the rear wing 38 are all substantially rectangular in shape. Recessed portions are provided between the first and second panels 42, 44 of the front wing 40 and between the first and second panels 46, 48 of the rear wing 38. The recessed portions define radiused corners when the first panel 42 is folded over the second panel 44 and the second panel 48 is folded over the first panel 46 during assembly. The first panel 42 of the front wing 40 and the second panel 48 of the rear wing 38 also have chamfered corners opposite the recessed portions. The first panel 42 of the front wing 40 has longitudinally extending glue lines G2. The second panel 48 of the rear wing 38 has longitudinally extending glue lines G3. It will be appreciated, however, that the glue lines G2 and G3 are only an example and could be in other locations as required.

[0066] In this embodiment, the receiving portion of the closure is a loop 50 projecting from the rear wing 38 and configured to extend through a cut-out in the front wing 40. The loop 50 is formed between the first and second panels 46, 48 of the rear wing 38. In this embodiment, the loop 50 is substantially rectangular and defined by first and second transversely extending voids 52, 54 cut through and bridging the first and second panels 46, 48 of the blank 41. In this embodiment, the loop 50 is defined by four longitudinally extending fold lines L4. The loop 50 has a length in the direction of the axis A-A that a sufficiently large contact area is defined between the loop 50 and blocking element 78 such that the opening of the bag 10 is strongly opposed in the first position. In this embodiment, there is a single receiving portion in the form of a single loop 50. In other embodiments, it will be appreciated that a plurality of receiving portions may be provided, for example a plurality of loops 50. In such embodiments, the front wing would include a plurality of cut-outs corresponding to the plurality of loops 50. In addition, the front and rear faces of the bag 10 would include a plurality of recesses 19 corresponding to the multiple loops 50.

[0067] In this embodiment, the loop 50 is moveable between flat and erected conditions. The flat condition is shown in Figure 1 where the surface of the loop 50 is parallel with the panels 46, 48. As can be seen in, for example, Figures 5 to 7, in the erected condition, the loop 50 has been 'popped up' such that it can extend through the front wing 40 of the clip 36. Advantageously, forming the loop 50 in the flat condition aids manufacture of the clip 36 as it can be passed down a line of an automated gluer machine before the loop 50 is then erected as part of the assembly process. In this embodiment, a substantially oval shaped aperture 56 is defined through the panel 46 of the rear ring 38. When the second panel 48 is folded over so it overlies the first panel 46 during assembly, the aperture 56 is configured to substantially align with the loop 50. Specifically, the aperture 56 is an opening leading to a pushable surface 58. When a force is applied to the pushable surface 58, the loop 50 is moved to the erected condition. In alternative embodiments, however, a force could instead be applied the surface of the loop 50 itself, adjacent to the pushable surface 58, to move the loop 50 to the erected condition.

[0068] A cut line defines a projection 60. The projection 60 of the loop 50 is configured to engage the front wing 40 (described in more detail below) to help hold the front and rear wings 40, 38 together.

[0069] The first panel 42 of the front wing 40 includes a recess 62 and the second panel 44 of the front wing 40 includes a recess 64. The recesses 62, 64 are substantially rectangular and are configured to align when the first panel 42 is folded about the fold line LI to overlie the second panel 44. The recesses 62, 64 are configured to align with the loop 50 of the rear wing 38 when the front and rear wings 40, 38 are folded about the fold lines L3. As shown in, for example, Figures 5 to 7, during assembly, the loop 50 is passed through the recesses 62, 64 as well as the recesses 19 of the bag 10, such that the loop 50 projects from the rear wing 38 through the front wing 40. The projection 60 of the loop 50 is configured to engage an edge of the recess 64 in the front wing 40 to help hold the front and rear wings 40, 38 together.

[0070] In this embodiment, the catch arrangement 66 is also defined in the front wing 40. The catch arrangement 66 includes a contact surface 73 and an opening 68. The contact surface 73 is defined in the first panel 42 of the front wing 40 in this embodiment. A catch layer 72 is an area of material defined within the footprint of the recess 62. In this embodiment, the catch layer 72 is foldable about a transversely extending fold line L5 such that the recess 62 has its rectangular shape once the catch layer 72 is folded. At a free end opposite the fold line L5, is a transversely extending engaging edge 74. In this embodiment, the engaging edge 74 is part of a recessed portion of the free end of the catch layer 72.

[0071] The catch layer 72has a longitudinally extending glue line G4 to fix the catch layer 72 to the first panel 42 of the front wing 40 once it has been folded about the fold line L5. The area of the first panel 42 that the catch layer 72is fixed to defines a reinforcing layer 76. The contacting surfaces of the overlapping catch layer 72 and the reinforcing layer 76 define a double layer of material that is engaged by a portion of the blocking element 78, as described in more detail below. An underside of the catch layer defines a contact surface 73. In other words, an opposite face of the catch layer 72 of the blank 41 as shown in Figure 1 defines a contact surface 73. As can be seen in Figure 7, the contact surface 73 faces and is located within the opening 68 when the clip 36 is assembled. When the blocking element 78 is inserted into the opening 68, it contacts the contact surface 73 and slides along it towards the engaging edge 74 during assembly of the closure 34. Once the blocking element 78 has been inserted into the opening 68 a sufficient amount, it will catch on the engaging edge 74 (as described in more detail below) and cannot be removed without breaking the blocking element 78.

[0072] The second panel 44 of the front wing 40 includes the opening 68. The opening 68 can be any suitable shape to correspond to the shape of the blocking element 78. A transversely extending fold line L6 defines a flap portion 70, configured to help feed the blocking element 78 into the opening 68. Once the blocking element 78 is inserted, the frictional engagement of the flap portion 70 of the catch arrangement 66 and the blocking element 78 may also help to retain the blocking element 78 in the first position. The opening 68 is configured to align with the contact surface 73 when the first panel 42 overlies and is fixed to the second panel 44. Therefore, as described in more detail below, during assembly, when the blocking element 78 is inserted into the opening 68, it is guided by the contact surface 73 towards the engaging edge 74 of the catch layer 72.

[0073] First and second blocking elements 78, 79 are shown in Figures 2 and 3. The first and second blocking elements 78, 79 are substantially identical except for directional indicators (described in more detail below). Therefore, the first blocking element 78 will be described, but the description also applies to the second blocking element 79. In this embodiment, the blocking element comprises an elongate strip portion 80. As described in more detail below, the elongate shape of the strip portion 80 aids assembly, when the blocking element 78 is threaded through the loop 50 to engage the catch arrangement 66. The blocking element 78 has an enlarged head portion 82 at a first end of the strip portion 80. After assembly of the closure 34, the head portion 82 is arranged to be opposite where the blocking element 78 engages the catch arrangement 66, so the head portion 82 can be engaged by a user to pull the strip portion 80 towards the second position and disengage the blocking element 78 from the catch arrangement 66. As shown in, for example, Figure 10, in the first position, the head portion 82 is configured to abut against the loop 50 to limit movement of the blocking element 78 beyond the head portion 82. This prevents the blocking element 78 being moved into an alternative position where access to the opening 12 of the bag 10 is permitted by moving the blocking element 78 too far past the loop 50.

[0074] In this embodiment, the head portion 82 of the blocking element 78 has a directional indicator 90 pointing. For the first blocking element 78, the directional indicator points in a second direction D2(see Figure 8) indicating the direction the blocking element 78 needs to be moved in to disengage from the catch arrangement 66. For the second blocking element 79, the directional indicator 90 points in a first direction Dl(see Figure 8) indicating the direction the blocking element 78 needs to be moved in to engage the catch arrangement 66. This indicates to the user how to open or re-close the bag 10. The directional indicator 90 could be an arrow or similar, to improve the user experience. In this embodiment, the arrows are cut into the first and second blocking elements 78, 79, but in alternative embodiments they could be printed or fixed to the first and second blocking elements 78, 79 in any suitable way. The second blocking element 79 is arranged to be stored in the bag 10 such that the bag 10 can be re-closed once the first blocking element 78 is broken. Advantageously, if the user wishes to return goods, they can use the second blocking element 79 to securely re-close the bag 10 before it is sent back.

[0075] The blocking element 78 has a transversely extending fold line defining an end portion 84 of the blocking element 78. In this embodiment, the end portion 84 is folded over in the first position (see for example Figure 8). The end portion 84 is configured to engage the catch arrangement 66. In this embodiment, an abutting edge 85 (see Figure 2) of the folded over end portion 84 abuts the engaging edge 74 of the catch layer 72 of the catch arrangement 66. The folded over end portion 84 retains the blocking element in the catch arrangement 66 without any additional components or fixing arrangement such as adhesive bonding being required. As the abutting edge 85 of the blocking element 78 abuts the engaging edge 74 of the catch arrangement 66, the end portion 84 and at least part of the strip portion 80 of the blocking element 78 are sandwiched by the layers of the catch arrangement 66. There is no space for the end portion 84 to unfold again and so the end portion 84 of the blocking element 78 is retained in the catch arrangement 66.

[0076] The blocking element 78 must be broken by at least part of the end portion 84 being separated from the remainder of the blocking element 78 so that the blocking element 78 can be removed from the catch arrangement 66 and loop 50 and the bag 10 opened. In this embodiment, the blocking element 78 has a weakened portion configured to be broken when the predetermined force is applied to the blocking element 78. The fold line defining the end portion 84 is defined by a first transversely extending fold line part L7 and a second transversely extending fold line part L8. Bridging the first and second fold line parts L7, L8 is a cut line 86. In this embodiment, the cut line 86 is substantially circular in shape. When the end portion 84 is folded over, the cut line 86 defines a projection extending longitudinally in the first direction Dlfrom the blocking element 78 in the form of a tip portion 88.

[0077] The first and second fold line parts L7, L8 and the cut line 86 together define the weakened portion, which helps to ensure a consistent breaking mechanism of the blocking element 78 when it is desired to move to the second position.

[0078] The cut line 86 acts as a stress riser feature configured to concentrate stress in a failure zone of the weakened portion to break the blocking element 78 at the failure zone when the predetermined force is applied to the blocking element 78. The term "failure zone" denotes a region that has been predisposed and designed to separate in response to the application of the predetermined force. In other words, the failure zone provides the weakened portion of the blocking element 78 resulting in a localisation of applied stress that ultimately tears or ruptures the blocking element 78 along or near the failure zone. The tearing or rupture of the blocking element 78 in the failure zone provides a clear visual clue that the shipping bag has been opened to discourage interference with packaged items.

[0079] Specifically, in this embodiment, the cut line 86 acts as the stress riser by concentrating stress. The material at the end portion 84 therefore cannot distribute the load as effectively as the rest of the material, leading to a higher stress concentration at the first and second fold line parts L7, L8. In terms of fracture mechanics, the presence of the cut line 86 lowers the amount of energy required for a crack or tear to propagate. It will also be appreciated that other means for creating a stress riser are conceivable, for example a relatively deep continuous score caused by a creasing tool, or a sharp angle or bend in the blocking element that will concentrate a force.

[0080] When the end portion 84 of the blocking element is folded and the blocking element 78 is in the first position, the cut line 86 is configured such that the adjacent material is subject to Mode III (out-of-plane shear) loading conditions. Under these conditions, the material on either side of the cut line 86 experiences shear forces that act perpendicular to the plane of the cut. This configuration facilitates a controlled tear, with the material tearing in a predictable manner, separating part of the end portion 84 from the remainder of the blocking element 78. In this embodiment, the part of the end portion 84 that is removed is sheared from the remainder of the blocking element. As shown in Figure 13, the material that is removed defines a nub 92. Once the nub 92 is separated from the remainder of the blocking element 78, the blocking element 78 can be disengaged from the catch arrangement 66.

[0081] The semi-circular shape of the cut line 86 in this embodiment is a continuous line of uniform curvature. Such a geometry inherently facilitates a predictable tear path due to the consistent rate of change in direction along the curve. In essence, the tear initiated at the cut line 86 is constrained by the curved boundary on either side. As a tear tends to propagate in a direction perpendicular to the highest tensile stress, the uniform curvature creates a steady stress gradient that guides the tear along the path of the curve.

[0082] Assembly of the closure 34 will now be described. Firstly, looking at Figure 1, the clip 36 is formed by folding the catch layer 72 about the fold line L5 and fixing it to the reinforcing surface 76 of the first panel 42 with the glue line G4. The first panel 42 is then folded about the fold line LI to overlie and be fixed to the second panel 44 with the glue lines G2. The front wing 40 of the clip 36 is then defined. The second panel 48 is then folded about the fold line L2 to overlie and be fixed to the first panel 46 with the glue lines G3. The rear wing 38 is then defined. Force is applied to the pushable surface 58 through the aperture 56 to erect the loop 50.

[0083] Figures 5 to 10 show assembly of the closure 34 on the bag 10. As shown in Figure 5, the clip 36 is located on the top of the bag by engaging the rear fringe 32 of the bag 10 with the rear wing 38 of the clip 36. The loop 50 projecting from the rear wing 38 is inserted through the recesses 19 of the bag 10 so it projects from the front fringe 30 of the bag, as shown in Figure 6. The front wing 40 of the clip 36 is then engaged with the front fringe 30 of the bag, as shown in Figure 7. The loop 50 passes through the recesses 62, 64 so it projects from the front wing 40 of the clip 36.

[0084] As shown in Figures 8 and 9, the end portion 84 of the blocking element 78 is folded about the fold line and then the blocking element 78 is moved in the first direction Dlthrough the loop 50 and into the opening 68 in the front wing 40 of the clip 36. The contact surface 73 located below the opening 68 directs the blocking element 78 such that the abutting edge 85 of the end portion 84 of the blocking element engages the engaging edge 74 of the catch layer 72.

[0085] In the first position, as shown in Figure 10, the abutting edge 85 of the end portion 84 of the blocking element 78 engaging the engaging edge 74 of the catch layer 72retains the blocking element 78 in the catch arrangement 66. As the catch layer 72 is folded over about the fold line L5 to locate substantially parallel to the reinforcing layer 76, the engaging edge 74 is defined to face in the first direction. Therefore, when the engaging edge 74 is engaged by the abutting edge 85 of the end portion 84, the blocking element 78 cannot move in the second direction D2. The contact surface 73 allows the end portion 84 of the blocking element 78 to slide in the direction of the engaging edge 74 and the abutting edge 85 of the blocking element 78 into engagement with the engaging edge 74 of the catch arrangement 66. Advantageously, the catch arrangement 66 cannot be easily accessed, so the blocking element 78 cannot be easily manipulated to bypass the tamper-proof mechanism. As the end portion 84 is sandwiched by the layers of the catch mechanism 66, the frictional engagement, as well as there being no space for the end portion 84 to unfold again, retains the blocking element 78 in the catch arrangement 66 in the first position. The blocking element 78 can only be removed by a sufficient force being applied that the end portion 84 breaks away from the remainder of the blocking element 78. As the loop 50 is fixed relative to the rear face of the bag 10 and passes through the front face of the bag 10, when the blocking element 78 is received in the loop 50 as shown in Figure 10, the first and second faces of the bag 10 cannot be separated and the opening cannot be accessed. As the blocking element 78 blocks access to the opening 12 of the bag 10 when it is located in the loop 50 and engages the catch arrangement 66, the contents of the bag are protected.

[0086] When a user wishes to open the bag 10, as shown in Figure 11, they can apply a force in the second direction D2 to move the blocking element 78 to break it, disengage it from the catch arrangement 66 and remove it from the loop 50. Figures 11 to 12 illustrate the steps of releasing the closure 34. The resulting force applied to the blocking element 78 is concentrated by the semi-circular cut line 86 to the regions of the end portion 84 adjacent the cut line tips, which define a failure zone of the end portion. In terms of fracture mechanics, these failure zones are essentially placed in a mode III loading configuration where the material either side of the cut line 86 is being sheared in opposite directions perpendicular to the plane of the cut line 86. This is because, while the blocking element 78 is being pulled longitudinally in the second direction, the tip portion 88 is pinned down in its orientation extending along the first direction. In this way, the semi-circular cut line 86 acts as a stress riser which directs failure along a predetermined path starting from the tip portion 88.The tip portion 88 is arranged to contact a layer of the clip 36 when located within the catch arrangement 66. In this embodiment, the tip portion 88 contacts the first panel 42 of the front wing 40. Therefore, when the blocking element 78 is moved in the second direction D2, the tip portion 88 will catch on the material of the first panel 42.

[0087] Once a predetermined force is reached, the tip portion 88 can no longer resist the stress and tearing is initiated from the tip portion 88. As the blocking element 78 continues to be moved in the second direction, the failure zone at the tear front moves further along the folded end portion 84 of the blocking element 78 as the tear grows. Eventually, the blocking element 78 is broken and released from the catch arrangement 66.

[0088] When the blocking element 78 is then removed from the loop 50, access to the opening of the shipping bag is permitted, as shown in Figure 12.

[0089] Figure 13 illustrates the broken blocking element 78 following release of the closure. As can be seen, the semi-circular cut line 86 facilitates a predictable and distinctive breakage pattern in which a central region of the folded end portion 84 radiating outwards from the semi-circular cut line 86 is torn or severed from the elongated strip to define the nub 92. This predictable tear path is a result of the consistent rate of change in direction along the semi-circular cut line 86. In essence, the tear initiated at the tip of the cut line 86 is constrained by the curved boundary on either side. As a tear tends to propagate in a direction perpendicular to the highest tensile stress, the uniform curvature of the cut line 86 creates a steady stress gradient that guides the tear along the path of the curve. In this way, the distinctive breakage pattern of the pull tab following release of the closure provides a clear indication that the bag 10 has been opened and therefore functions as an effective tamper-evident mechanism.

[0090] Where the word 'or' appears this is to be construed to mean 'and / or'. This is such that items referred to are not necessarily mutually exclusive and may be used in any appropriate combination.

[0091] The invention has been described above with reference to one specific embodiment. However, it will be appreciated that various changes and modifications can be made without departing from the scope of the invention as defined in the claims.

[0092] In an alternative embodiment, rather than the abutting edge 85 of the end portion 84 of the blocking element 78 engaging the engaging edge 74 of the catch layer 72, the end portion 84 could instead locate between the catch layer 72 and the reinforcing layer 76 and the engaging edge 74 would instead by engaged by the fold line that the end portion 84 is folded about. In this embodiment, the glue line G4 would be modified such that a retaining slot is defined between the catch layer 72 and the reinforcing layer 76 for locating the end portion 84.

[0093] The appended claims set out particular combinations of features described above. However, the scope of the present disclosure is not limited to these particular combinations claimed. Instead, the scope of the present disclosure extends to encompass any combination of features herein disclosed.

Claims

1. A closure for a shipping bag having an opening, the closure comprising:a blocking element movable between a first position in which access to the opening of the shipping bag is blocked and a second position in which access to the opening of the shipping bag is permitted;a clip configured to be located over the opening of the shipping bag, wherein the clip comprises a first wing and a second wing configured to respectively engage first and second faces of the shipping bag, the clip comprising:a receiving portion in the form of a loop projecting from the first wing and configured to extend through a cut-out in the second wing to receive the blocking element; anda catch arrangement defined in the second wing and configured to be engaged by the blocking element,wherein, in the first position, the blocking element is received in the receiving portion and engages the catch arrangement,wherein the blocking element is configured to break under application of a predetermined force to disengage from the catch arrangement and enable the blocking element to be moved from the first position to the second position such that the blocking element is removed from the receiving portion and access to the opening of the shipping bag is permitted.

2. The closure according to claim 1, wherein the blocking element is configured to be moved in a first direction to engage the catch arrangement and configured to be moved in a second direction opposite to the first direction to disengage from the catch arrangement.

3. The closure according to claim 2, wherein the catch arrangement comprises an engaging edge configured to be engaged by the blocking element in the first position to impede movement of the blocking element in the second direction.

4. The closure according to claim 3, wherein the blocking element comprises an end portion that is folded over in the first position and the end portion abuts the engaging edge of the catch arrangement.

5. The closure according to claim 4, wherein the catch arrangement comprises a contact surface and an opening, such that during assembly of the closure the blocking element can be inserted into the catch arrangement through the opening of the catch arrangement, and the end portion of the blocking element is guided in the first direction along the contact surface such that the end portion engages the engaging edge of the catch arrangement.

6. The closure according to claim 5, wherein the end portion of the blocking element comprises an abutting edge, and the abutting edge of the end portion of the blocking element engages the engaging edge of the catch arrangement.

7. The closure according to claim 6, wherein the contact surface is defined by a catch layer that has been folded about a fold line and fixed to a reinforcing layer, wherein the fold line is defined at an end of the catch layer opposite the engaging edge of the catch layer.

8. The closure according to any previous claim, wherein the catch arrangement further comprises a flap portion configured to guide the blocking element into the opening of the catch arrangement.

9. The closure according to any previous claim, wherein the blocking element comprises a weakened portion configured to be broken when the predetermined force is applied to the blocking element.10.The closure according to claim 9, wherein the weakened portion comprises a stress riser feature configured to concentrate stress in a failure zone of the weakened portion to break the blocking element at the failure zone when the predetermined force is applied to the blocking element.11.The closure according to claim 10 when dependent on claim 4, wherein the stress riser feature comprises a cut line bridging first and second parts of the fold line defining the end portion of the blocking element.12.The closure according to claim 11, wherein the end portion of the blocking element is folded over about the first and second parts of the fold line such that the cut line defines a tip portion extending in the first direction from the first and second parts of the fold line.13.The closure according to claim 3, wherein the loop is moveable between flat and erected conditions, wherein the loop is configured to extend through the second wing in the erected condition.14.The closure according to claim 7, wherein the second wing is defined by a first panel connected to a second panel with a fold line, wherein the first panel is configured to overlie and be fixed to the second panel, wherein the first panel comprises the catch layer that includes the engaging edge and the reinforcing layer.15.The closure according to any previous claim, wherein the first panel of the second wing comprises a recess and the second panel of the second wing comprises a recess, wherein the recess of the first panel is configured to align with the recess of the second panel, and the recess of the first panel and the recess of the second panel are configured to align with the loop projecting from the first wing when the second wing overlies the first wing such that the loop extends through the cut-out in the second wing.16.The closure according to any previous claim, wherein the blocking element comprises an elongated strip portion.17.The closure according to claim 16, wherein the blocking element further comprises an enlarged head portion at an end of the blocking element opposite where the blocking element engages the catch arrangement, the head portion configured to be engaged by a user to pull the strip portion towards the second position.18.The closure according to any previous claim, wherein the blocking element is a first blocking element, and the closure further comprises a second blocking element arranged to be stored in the shipping bag such that the shipping bag can be reclosed once the first blocking element is broken.19.The closure according to any previous claim, wherein the closure is formed from a paper-based material.

20. A shipping bag having first and second faces, the shipping bag including the closure of any previous claim, wherein the first wing of the closure engages the first face of the shipping bag, and the second wing of the closure engages the second wing of the shipping bag.Application No:     GB2318876.6Claims searched:    1-20Examiner: Mr Joe CornfieldDate of search: 15 March 2024Patents Act 1977: Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance X 1-6, 8-10, 16-18, 20 GB2150531 A MOREL A loop 14 on one surface 9 extendable through a hole 13 in another surface 19; a frangible blocking element 22 extendable through the loop and engageable with a catch 15 on the apertured surface 19; the bolt removable from the loop upon breaking, (abstract, figs) x,& 1-3, 9-12, 16, 17, 20 EP0422905 Al N ETT O A loop 17 on one surface 11 extendable through a hole 21 in another surface 3; a frangible blocking element 27-30 extendable through the loop and engageable with a catch 22, 23 on the apertured surface 11; the bolt removable from the loop upon breaking, (abstract, figs) x,& 1-3, 9-12, 16, 17, 20 US5118148 A N t 1 1 U A loop 17 on one surface 11 extendable through a hole 21 in another surface 3; a frangible blocking element 27-30 extendable through the loop and engageable with a catch 22, 23 on the apertured surface 11; the bolt removable from the loop upon breaking, (abstract, figs) X 1-18, 20 US4175782 A N ETO A loop 20 on one surface 4 extendable through a hole 25 in another surface 6; a frangible blocking element 28 extendable through the loop and engageable with a catch 26 on the apertured surface 6; the bolt removable from the loop upon breaking, (abstract, figs) X 1-18, 20 FR2306137 Al N t 1 1 U A loop 19 on one surface 16 extendable through a hole 20 in another surface 21; a frangible blocking element 1 extendable through the loop and engageable with a catch 28 on the apertured surface 20; the bolt removable from the loop upon breaking, (abstract, figs) A - EP0257978 A2 J E N N1NGS A rod projecting through loops to close a bag mouth, (abstract, figs)22Categories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of same category. before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:International Classification:Subclass Subgroup Valid From B65D 0027 / 28 01 / 01 / 2006 B65D 0027 / 30 01 / 01 / 2006 B65D 0033 / 34 01 / 01 / 2006

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