PACK AND METHOD AND APPARATUS FOR MAKING A PACK

Field of the Invention

The present invention relates to a pack for articles such as cigars, cigarillos and cigarettes. The invention also relates to a blank for forming the pack, and a method and apparatus of making the pack.

Background

A prismatic pack that is of triangular cross-section is known from WO 01/44077. In one example of the known pack, the pack is formed of a rectangular blank divided by crease lines into four panels, three of which form the sides of the pack and the fourth is a connector which connects the outer two of the three panels. The blank has, attached to opposite top and bottom edges of one panel, triangular panels which define the cross-sectional shape of the pack. In this one example of the blank (Fig 5), two connecting flaps are connected to respective edges of each triangular panel. The flaps connect the triangular panel to the sides of the erected pack. In another example of the blank (Fig 20), for each triangular panel, there are two connecting triangular shaped flaps attached to respective side panels rather than to the triangular panel.

Summary of Invention

One embodiment of the invention provides a blank for forming a prismatic pack of triangular cross-section. The blank has a generally rectangular portion which is divisible into three body panels for forming the sides of the triangular cross-section. A top triangular panel is connected to the top edge of one of the body panels and a bottom triangular panel is connected to the bottom edge of one of the body panels. The top and bottom triangular panels correspond to the triangular cross-section of the pack. First and second top flaps are connected to the top edge of respective body panels, other than the body panel to which the top triangular panel is connected. Each of the first and second top flaps extends along substantially the whole width of its respective body panel. The first top flap is substantially similar in size and shape to the top triangular panel. First and second bottom flaps are connected to the bottom edge of respective body panels, other than the body panel to which the bottom triangular panel is connected. Each of the first and second bottom flaps extends along substantially the whole width of its respective body panel. The first bottom flap is substantially similar in size and shape to the bottom triangular panel.

The resulting triangular pack has triangular ends which, when viewed from the sides, have complete fold lines extending along the whole length of the straight portion of each side. Any gaps which may appear at the vertices of the triangular ends are minimised, thus improving the appearance and closure of the pack. The use of a triangular panel and triangular flaps of substantially equal size and shape stiffens the ends to improve rigidity of the pack. The form of the blank in having end panels and flaps extending only from the edges of the body panels, and no further flaps extending from the end panels or from the flaps themselves, simplifies erection of the pack, especially in respect of an automated folding procedure.

In one embodiment, the first top flap is slightly smaller than the top triangular panel and the first bottom flap is slightly smaller than the bottom triangular panel. This helps the top and bottom flaps to fold under the top and bottom triangular panels, respectively.

In one embodiment, the second top flap is connected to the body panel which is between the body panels connected to the top triangular end panel and the first top flap. Similarly, the second bottom flap is connected to the body panel which is between the body panels connected to the bottom triangular end panel and the first bottom flap. This helps to avoid interference when folding between the first top flap and the top triangular end panel, and likewise between the first bottom flap and the bottom triangular end panel.

Another embodiment of the invention provides a blank for forming a prismatic pack of triangular cross section. The blank has a generally rectangular portion which is divisible into a middle panel and two outer side panels; a top triangular panel and a bottom triangular panel connected to top and bottom edges of the rectangular portion; and a plurality of flaps for connecting the triangular panels to the side panels in the erected pack. One of the triangular panels has at least one free edge and the other panel has a flap attached to at least one edge.

Another embodiment of the invention provides a blank for forming a prismatic pack of triangular cross-section. The blank has a generally rectangular portion which is divisible into a middle panel and two outer side panels; a top triangular panel connected to the top edge of one of said side panels and a top flap connected to the top edge of another of the side panels; a bottom triangular panel connected to the bottom edge of one of said side panels and a bottom flap connected to the bottom edge of another of the side panels; the top and bottom triangular panels defining in the erected pack said triangular cross-section of the pack; a further flap connected to the top edge of the side or middle panel which has no top triangular panel or top flap connected thereto, the further flap being of length along the top edge substantially equal to the width of the side or middle panel to which it is connected; and a further flap connected to the bottom edge of the

side or middle panel which has no bottom triangular panel or bottom flap connected thereto, the flap being of length along the bottom edge substantially equal to the width of the side or middle panel to which it is connected; the top flap and further top flap being arranged so that, in the erected pack, each provides a continuous fold line across the panel to which it is attached and they together extend into the vertices of the triangular cross-section.

Another embodiment of the invention provides a prismatic pack of triangular cross-section having three body panels for forming the sides of the triangular cross-section. A top triangular panel is connected to the top edge of one of the body panels and a bottom triangular panel is connected to the bottom edge of one of the body panels. The top and bottom triangular panels correspond to the triangular cross-section of the pack. First and second top flaps are connected to the top edge of respective body panels, other than the body panel to which the top triangular panel is connected. Each of the first and second top flaps extends along substantially the whole width of its respective body panel. The first top flap is substantially similar in size and shape to the top triangular panel. First and second bottom flaps are connected to the bottom edge of respective body panels, other than the body panel to which the bottom triangular panel is connected. Each of the first and second bottom flaps extends along substantially the whole width of its respective body panel. The first bottom flap is substantially similar in size and shape to the bottom triangular panel.

According to a further aspect of the invention there is provided a pack having a prismatic form with a substantially triangular cross-section comprising three major panels and two closed ends, each of the two closed ends being formed by overlapping end panels and end flaps that extend from the major panels, wherein the end panels and end flaps are arranged such that on each edge of the closed ends, a continuous fold line across the major panel to which the end panel or end flap attaches is provided.

According to a further aspect of the invention, there is provided an apparatus for making a pack of prismatic form, which pack has a substantially triangular cross-section. The apparatus comprises at least one arbour of substantially triangular form, blank application means for applying a blank to the arbour, and rotational drive means operable to rotate the arbour to effect folding the blank to form a prismatic pack of substantially triangular cross-section.

According to a further aspect of the invention, there is provided a method of making a pack of prismatic form and having a substantially triangular cross-section. The method comprises applying a blank to an arbour of triangular cross-section; rotating the arbour to effect folding of the blank into a hollow prismatic form of triangular cross-section having one closed end and one open end; inserting a product or bundle of product shaped to be received in the pack; and closing the

open end to provide a pack of prismatic form of substantially triangular cross-section and closed at both ends.

In an alternative embodiment, a bundle of product is used as a support for folding the blank instead of an arbour. In this embodiment, the product bundle may first be enclosed completely within a foil wrapper to hold the product in place, prior to using the bundle as a support for folding the blank.

Brief Description of the Drawings

Various embodiments of the invention are now described in detail by way of example only with reference to the following drawings:

Figure 1 is a perspective view of a prismatic pack of triangular cross-section in accordance with one embodiment of the invention;

Figures 2, 3 A, 3B and 3C depict various embodiments of blanks for forming the pack of Figure 1;

Figure 4 A is a perspective view of the pack of Figure 1 with the lid open;

Figure 4B shows a blank including an integral inner frame section in accordance with one embodiment of the invention;

Figure 4C illustrates a partial top view of a pack made from the blank of Figure 4B;

Figure 5 is a top perspective view of an apparatus for making a pack from a blank such as depicted in Figure 2 in accordance with one embodiment of the invention;

Figure 6 is a schematic front view of the stations of an arbour carousel of the apparatus of Figure 5 during assembly of a pack in accordance with one embodiment of the invention;

Figure 6A is a schematic front view of the stations of an arbour carousel during assembly of a pack in accordance with another embodiment of the invention;

Figure 7 depicts the assembly of an end of a pack in accordance with one embodiment of the invention;

Figure 8 is a flow chart summarising a method of making a pack of substantially triangular cross-section in accordance with one embodiment of the invention;

Figures 9 to 14 show blanks according to various embodiments of the invention for forming the pack of Figure 1;

Figure 15 illustrates the blank of Figure 14 having an integral inner frame; and

Figure 16 is a top view of a partially assembled pack made from the blank of Figure 14 or 15.

Detailed Description

Figure 1 illustrates a hinged-lid pack 20 in accordance with one embodiment of the invention. The pack 20 is substantially rigid and has a prismatic shape with the cross-section of an equilateral triangle. The cross-sectional shape is defined by a triangular top panel 21 and a triangular bottom panel 25. The pack 20 has a container portion 6 and a lid portion 8, separated by a separation line 19. The container portion 6 has side (body) panels 11, 12 and 13 and the lid portion has side (body) panels 15, 16 and 17 respectively. The side or body panels are substantially rectangular and extend parallel to the longitudinal axis of the prism. In the example of Figure 1, the pack 20 has rounded edges 341, 341', 342, 342' (visible in Figure 1) and edges 343, 343' (not visible in Figure 1) between the body panels.

Figure 2 shows a blank 10 in accordance with one embodiment of the invention. Blank 10 may be of card or any other suitable material. Blank 10 comprises a generally rectangular section divided by three pairs of crease zones 342, 342'; 341, 341'; and 343, 343', and with top and bottom edges 30, 31. The top and bottom edges 30 and 31 may represent pre- weakened fold lines for end panels and flaps, as described in more detail below. The first crease zone of each pair forms an edge of the container portion 6 of the erected pack 20 and the latter crease zone of each pair forms a corresponding edge of the lid portion 8 of the erected pack 20. In pairs, the crease zones 342, 342'; 341, 341'; and 343, 343' extend from the top edge 31 to the bottom edge 30 of the blank and lie parallel to the side edges 381 and 382 of the blank 10.

The crease zones 342, 342'; 341, 341 '; and 343, 343' correspond to the rounded edges of the pack 20 shown in Figure 1 and divide the blank 10 into the body panels 11+15, 12+16, and 13+17, which form the sides of the erected pack 20. The body panels are joined to one another along their longitudinal margins. Connecting panels 14, 18 extend from the edge 343, 343' and are arranged to overlap with and adhere to panels 13 and 17 (e.g. using glue) to fix the form of the erected pack 20.

A cut defines a demarcation line 19 between the lid portion 8 and the container portion 6. The demarcation line 19 extends across the blank 10 to define the panels 11 and 12 of the container portion 6 of the erected pack from panels 15 and 16 of the lid portion 8 of the erected pack. Similarly, the demarcation line separates crease zone 342 from crease zone 342', crease zone 341 from crease zone 341', and crease zone 343 from crease zone 343 '. A crease line 28 dividing the connecting panels 14 and 18 is aligned with a corresponding crease line 27 dividing the side panels 13 and 17 to provide a hinge for the lid portion 8. The crease lines 28 and 27 are linked to opposite ends of the demarcation line 19.

In the example of Figure 2, top and bottom triangular panels 21 and 25 are connected to the panels 17 and 13 respectively and hence lie at opposite ends of one face (body panel) of the erected pack. The top and bottom triangular panels 21 and 25 form the exterior end panels in the erected pack 20, perpendicular to the body panels (see Figure 1), and hence have a size and shape that corresponds generally to the triangular cross-section of erected pack 20. Note that neither triangular panel 21 nor triangular panel 25 has any flaps on the edges thereof. These edges can therefore be considered as free, in that they have no appendages.

In the embodiment of Figure 2, panel 13 forms the back of the pack, in that it includes the hinge line 17 for the lid. Thus the material of the blank is continuous through body panel 13, the hinged lid panel 17, and the triangular top end panel 21, for improved strength and closure.

Side panels 11 and 15 are provided with triangular flaps 125 and 121 respectively (at edges 30 and 31 respectively). Triangular flaps 121 and 125 therefore lie at opposite ends of one face (body panel) of the erected pack. The triangular flaps 121 and 125 are of the same shape as, but slightly smaller than, the triangular panels 21, 25.

The middle panel 12 has a substantially rectangular flap 26 attached along bottom edge 30 and the middle panel 16 has a corresponding rectangular flap 22 attached along the top edge 31. Each of the rectangular flaps 22, 26 extends along edge 31, 30 respectively a distance substantially equal to the distance between crease zones 341' and 342'. This distance is also substantially equal to the length of the junction of the triangular panels 21 and 25 with corresponding side panels 17 and 13 respectively.

In some other embodiments, the triangular end panels 21 and 25 of the blank 10 may be offset, i.e. each triangular end panel 21 and 25 may be attached to a different rectangular panel. For example, the triangular end panel 21 may extend from the top edge 31 of side panel 17, while the triangular end panel 25 may extend from the bottom edge 30 of the middle panel 12 (as for the embodiment of Figure 3A, as shown below). In this case, the end flaps 22, 121, 26 and 125 are then also offset in corresponding fashion.

In some other embodiments, triangular flaps 121, 125 may be provided on middle panels 12, 16, with the rectangular flaps 22, 26 provided on side panels 11, 15. However, such an arrangement may increase the risk of interference between triangular end panel 21 and triangular end flap 121, likewise for panel 25 and flap 125. In contrast, in the blank shown in Figure 2, flaps 22 and 26 can be sized to avoid any such interference.

In some embodiments, flaps 22 and 26 may have a shape other than rectangular. For example, flaps 22 and 26 may comprise truncated versions of triangular flaps 121, 125 (this would be more trapezoidal in shape, but with rounded sides to match the rounded edges of pack 20).

An example of how a pack may be erected using the blank of Figure 2 is as follows: a. Fold the panels 11, 15; 12, 16 and 13, 17 and the connecting panels 14, 18 relative to each other about the crease zones 342, 342'; 341, 341'; and 343, 343' into a triangular form having a cross-section the same size and shape as the triangular end panels 21 and 25; b. Overlap the connecting panels 14, 18 inside the side panels 13, 17 and stick together to fix the triangular form; c. Fold rectangular flaps 22 and 26 to be at right angles to their adjoining rectangular panels 16 and 12; d. Fold the triangular end flaps, 121 and 125 to be at right angles to their adjoining panels 15 and 11 respectively, so that the triangular end flaps 121 and 125 overlap and are glued to the outside of rectangular flaps 22 and 26, respectively; and e. Fold the triangular end panels 21 and 25 to be at right angles to their adjoining panels 17 and 13 respectively, so that the triangular end panels 21 and 25 overlap and are glued to the outside of triangular end flaps 121 and 125 respectively.

In the above process, the triangular flaps 121, 125 are glued to rectangular flaps 22 and 26, and the triangular panels 21 and 25 are glued to the triangular flaps 121 and 125 at a suitable time (or times) in the process.

The resulting triangular pack 20 has triangular ends that, when viewed from the sides, have complete fold lines extending along the whole length of the straight portion of each side. The triangular flaps 121 and 125 (and also the triangular panels 21 and 25) extend into the vertices of the triangular cross-section leaving substantially no gaps at the edges thereof and provide folded edges extending across substantially the whole width of each side panel. The provision of a triangular flap 121, 125 inside the corresponding triangular end panel 21, 25, where the triangular flap is of substantially the same size and shape as the end panel, provides extra strengthening and rigidity. For example, it helps to avoid any tendency for creasing of the top surface of the lid, which is stiffened by the presence of both triangular flap 121 and triangular end panel 21 of substantially the same size and shape.

In addition, it is noted that all three panels 17, 16, and 15 are provided with a panel or flap extending along substantially the whole top edge 31 of the relevant panel. Thus panel 17 is

provided with flap 21, panel 16 is provided with flap 22, and panel 15 is provided with flap 121. This configuration helps to avoid any gap forming between the end panel of the erected pack (i.e. panel 21) and the side faces of the pack. This improves the appearance of the pack, as well as helping with sealing of the pack to prevent unwanted ingress or egress (such as loss of moisture from tobacco contained within the pack). It will be appreciated that a similar arrangement without any gaps is also formed at the bottom of the pack by end panel 25, rectangular flap 26, and triangular flap 125.

In the particular embodiment of Figure 2, the erected pack has rounded edges between the main panels 11, 12, and 13. However, it will be appreciated that the edges of the erected pack may have any other suitable shape, for example, sharp or chamfered, in which case the form of the creased zones 341, 342, 343, and 341', 342' and 343' can be modified suitably to provide such edges. The shape of the corners/edges provided on the end panels and flaps is also suitably modified to have a corresponding shape. In particular, the panels and flaps can be arranged such that there are substantially no gaps at the vertices, and folded edges extend across substantially the whole width of each side panel.

It will be appreciated that manufacturing apparatus for cigarette packs is generally designed for a conventional rectangular pack. An example of an apparatus for folding the blank 10 of Figure 2 to form a triangular pack 20 is illustrated in Figure 5 and the assembly sequence is illustrated in Figure 6. A carousel 60 includes a series of twelve arbours 62 that are circumferentially spaced around the carousel 60 and each arbour 62 extends in a direction parallel to the rotational axis of the carousel to provide 12 assembly stations Sl -S 12 at which various assembly processes are progressively completed. (It will be appreciated that the number of arbours in carousel 60 may vary according to the number of stations involved in the assembly process and the rate of packs to be produced). The cross-sectional shape of the arbours matches the triangular cross-section of the pack 20.

The carousel 60 is rotated clockwise upon a fixed axis allowing the relevant arbour to rotate to the next station Sl-S 12. The progression of the relevant arbour 62 sequentially incorporates the assembly of a foil wrapper 50 (Sl) (to maintain product quality), the assembly of an inner frame 40 (S3) (when a separate inner frame is used), the assembly of a diecut blank 10 (S4), the insertion of a bundle of product 52 (SlO), and subsequent exit of a partially assembled pack from the arbour (Sl 1, S 12) to receive the final closure of the open end of the pack (not illustrated). During the progression of the arbour 62, various force folds F, plough folds P, and glue applications are applied to the foil wrapper 50, the inner frame 40, and the blank 10. Glue is applied to the pack in known manner as necessary during the process of erecting the pack.

Plough folding (P) always occurs against the direction of travel of the carousel 60, while force folding (F) can be performed in any direction relative to the direction of travel of the carousel, for example using machine actuated folding fingers. Plough folding may be used if the leading edge of the blank is a fold edge, whereas mechanism folding may be used if the leading edge if a cut or free edge. Plough folding uses the rotational force of the arbour carousel to create a fold when a stationary object, plough folding objects or folding edges are in the rotational path of the unfolded panels of the blank rotating with the arbour. In contrast, force folding uses a variety of moving apparatus in motion relative to the arbour and applying force to the panel to create the fold.

At station Sl, the bare arbour 62, which is substantially triangular in shape, receives a pre- cut foil wrapper 50 from a foil embossing and cutting device 70. Subsequently, the foil wrapper 50 is folded around the arbour 62, but leaving one end open (corresponding to the open end of the arbour), thereby creating a pocket for receipt of the bundle of product, for example cigarettes at station SlO. At station S3, the combination of the arbour 62 and the foil wrapper 50 receives the inner frame 40 from an inner frame cutting and creasing unit 80. Subsequently, the inner frame 40 is folded around the outside of the foil wrapper 50. At station S4, the blank 10 is fed into the arbour 62 by a blank feeding unit 90, for example, a conveyor. Subsequently, the blank 10 is folded around the arbour 62 and the previous cumulative materials of the progression. At station SlO, a bundle of product 52, which is arranged in the form of a substantially triangular shape, is inserted into the arbour 62.

When the relevant arbour 62 returns to the original starting point of the progression, station Sl, the partially assembled triangular pack is pushed out of the arbour onto an outlet conveyor 100. The open end of the pack 20 and foil wrapper 50 is subsequently folded and closed to form an assembled triangular pack 20. The relevant arbour 62 is again bare and ready to continue another progression around carousel 60.

As described above, the carousel 60 has twelve stations (Sl -S 12) in which various steps for the assembly of triangular pack 20 are completed. Each station (Sl -S 12) simultaneously conducts its assembly processes to allow for a continuous production of assembled triangular packs 20 as the arbour rotates.

As shown in Figures 5 and 6, the triangular pack 20 is made "base out". In other words, the container portion 6 with associated bottom end panel 25 is formed on an outside end 62b of the

arbour 62 away from the carousel 60. Further, in Figures 5 and 6, the leading edge of the blank 10 may be a fold edge as opposed to a free/cut edge to support plough folding (as described above).

As shown in Figure 6, at station Sl the leading surface 64 of the arbour 62 is positioned perpendicular to the direction of rotation of the carousel 60. The pre-cut foil wrapper 50 is fed into station Sl parallel to leading surface 64 of arbour 62. From station Sl to station S2, the foil wrapper 50 is force folded F and subsequently overlapped around the outside surface of arbour 62. From station S2 to station S3, the end of the foil wrapper 50 is plough folded P from the direction of the leading surface 64 of the arbour 62 and is force folded F from the other directions of the remaining surfaces of arbour 62. At station S3, the inner frame 40 is fed parallel to the leading surface 64 of the arbour 62 and placed on an inside end 62a of the arbour nearest the carousel 60 (since the pack 20 of the present embodiment is being made "base out").

From station S3 to station S4, the inner frame 40 is partially folded away from the direction of travel. At station S4, the blank 10 is fed parallel to the leading surface 64 of the arbour 62.

From station S4 to station S5 the remaining panels of the inner frame 40 are force folded F to complete the assembly and positioning of the inner frame 40. In addition, from station S4 to station S5 the panels of the blank 10 are force folded F to wrap around the inner frame 40, which in turn is wrapped around the foil wrapper 50 and the arbour 62. Force folding F of the panels forming the blank 10 results in an overlap - e.g. an overlap of the connector panel 14 and the exterior panel 13 of the blank 10 shown in Figure 2.

Referring to Figure 7 (in which foil wrapper 50 is shown as partly removed to show the underlying arbour 62), progress from station S5 to station S6 is illustrated, wherein the end flaps 26 and 125 are plough and force folded respectively, followed by the bottom end panel 25 being force folded to close the bottom end of container portion 6. In another embodiment, end flaps 26 and 125 are both force folded, with the bottom end panel 25 then being plough folded to close the bottom of the pack. Note that offsetting the top panel 21 and the bottom panel 25 (such as shown in Figure 3A, as discussed below) can allow for the bottom end panel to be plough folded, since the leading edge of the blank is then a fold edge rather than a cut or free edge of the blank. If bottom end panel 25 is able to be plough folded during assembly, this allows for the fold to be made against the direction of travel of the arbour on the carousel. Note that folding a relatively large end panel in the direction of travel (i.e. using force folding) is more complicated, since it involves actuating a folding edge or finger against the folded panel. Therefore, providing a blank design which allows for a large end panel to be plough folded enables the pack formation to be completed

more readily and helps to prevent tearing of the end panel, which is more likely to occur when leading with a cut or free edge.

At station SlO a bundle of product 52 is inserted into the hollow arbour 62 from the remaining open end of the triangular pack 20. The bundle of product 52 is pre-formed into a substantially triangular shape for insertion. Referring to Figure 5, from stations S8 through S12, a restrictor plate 66 is implemented to restrict the lateral movement of the pack and permits the bundle of product 52 to be inserted without pushing the pack off the arbour.

Once the relevant arbour 62 returns to station Sl, the bundle of product 52 is pushed out of the arbour 62, which in turn removes the partially assembled triangular pack 20 to the outlet conveyor 100. At the outlet conveyor 100, the remaining portion of the unfinished pack, including the top end panel 21, the two top end flaps 22 and 121, plus the foil wrapper 50, are subsequently folded to complete the triangular pack 20. Upon the removal of the pack 20 containing the bundle of product 52 from station Sl, the now emptied arbour 62 can begin the assembly process again.

The end of the pack that is closed in the assembly process Sl -S 12 may be the top end or the bottom end. The bundle of product described above may be a bundle of cigarettes. The orientation of cigarettes is usually such that the filter end of the cigarettes is arranged at the top of the pack. This orientation is suitable for assembly of a pack 20 as described above, a "base out" approach, because removal of the pack 20 from the arbour 62 is by pushing on the filter ends of the cigarettes, thereby reducing the risk of damaging the tobacco end of the bundle of cigarettes. Subsequent to removal from the arbour, the open end of the pack is closed, analogous to the closing of the other end, with the end panel 21 then forming the lid of the pack.

The process of Figures 5-7 may take place on a carousel 60 that has many arbours 62 such that the different steps take place in a continuous process at different positions on the carousel 60 as the arbours 62 travel around the carousel 60.

It will be appreciated that the blank may be folded on the support in the reverse orientation to that described above, i.e. working on the top end of the assembly and not the bottom. However, working on the bottom end of the assembly has the benefit that removal of the pack assembly from the support, when the support is an arbour, is facilitated by applying pressure to the filter rod end of the smoking articles within the pack assembly (which as noted above helps to avoid damage to the smoking articles).

The assembly process described above using a hollow arbour 62 is summarised in the flow-type diagram of Figure 8. It will be appreciated that the process could be conducted on a solid arbour. In this case, the product is inserted after the pack is removed from the arbour, but before closing the open end. In addition, or alternatively, the station S2 which introduces a foil sheet may be omitted if the bundle is pre-wrapped in foil instead of providing the foil around the arbour as described above. In this configuration, a wrapped bundle is introduced at station S6.

The above method describes forming a pack using a blank 10 in which the end panels and end flaps each extend from the major panels of the blank 10 and the blank has a separate inner frame 40. For example, with reference to the blank of Figure 2, the end panels 21 and 25, as well as flaps 22, 26, 121 and 125, are directly connected to the edges 30 and 31 of the rectangular portion of the blank. This configuration simplifies erection of the pack 20, because the triangular end panels 21 and 25 (and the flaps 121 and 125) are not themselves provided with flaps. This allows the main faces of the pack to be first folded around the arbour 62 (which determines the main form of the pack) without having later to tuck any flaps between the inside of the pack and the arbour (which would be a relatively complex operation). In contrast, known blanks with flaps attached to the triangular end panels are less suited to simple mechanical folding as the flaps depending from the end panels cannot be easily folded when the body of the pack is already erected. Furthermore, such known blanks are also generally less suited to forming a pack on a support prior to inserting the contents of the pack as the flaps cannot be easily folded into a pre- erected body without fouling the edge of the container of the pack.

Figure 3A represents an alternative form of the blank 10 of Figure 2. Figures 3B and 3C are partial views of further alternatives of the blank 10 of Figure 2. The alternative blanks of Figures 3A, 3B and 3C comprise end panels 21, 25 of triangular cross-section (as for the blank of Figure 2). The flaps 223, 222; 131, 133; and 135, 136 have a profile which is not triangular. However, at least one edge of such a flap may be shaped to correspond with the vertex of a triangular shape. As a result, when the blank is assembled, there are substantially no gaps at the vertices and a folded edge that extends across substantially the whole width of each side panel is provided on each panel of the erected pack.

Referring to Figure 3B, the triangular flap 121 (shown in dash lines in Figure 3B) of Figure 2 is replaced by a flap 133 having rounded ends 133', 133" which, in the erected pack, extend into two of the vertices of the triangular cross-section. Flap 133 is a truncated version of triangular flap 121. The flap 131 of Figure 3B, corresponding to flap 22 of Figure 2, may have a rounded end 134 to extend into the third vertex.

To minimise gaps at the vertices, the end panels and flaps may be arranged such that at least one of the flaps has one or more of its edges shaped to extend into and correspond with the shape of the vertex. Alternatively, each flap may have at least one edge that is shaped to extend into or correspond with the shape of the vertex, wherein each flap has a different edge shaped such that an edge of a flap and an edge of the end panel extends into and corresponds with the shape of the vertex. For example, in the embodiment of Figure 3C, flap 135 is provided with at least one rounded edge (135') and flap 136 is provided with a corresponding round edge 136'. Note that end flaps 22 and 26 in the embodiment of Figure 2 may also have one or both of their ends rounded. Thus Figure 3C is similar to Figure 3B, except that flap 135 (corresponding to flap 22/131) and flap 136 (corresponding to triangular flap 121) each has one rounded end 134, 136' to extend into a respective vertex. Flap 135 and/or flap 136 may have two rounded ends (e.g. 134 and 135' for flap 135).

As mentioned above, the assembled pack 20 may also include an inner frame section 40 as illustrated in Figure 4A. The inner frame is located within the pack in such a way that it projects partly from the open top end of the container portion. The bottom of the inner frame may extend all or only part of the way to the bottom of the pack. As shown in Figure 4 A, the top edge of the inner frame projecting from the container portion of the pack has a profile substantially parallel to the free edge 19 of the container portion 6 of the pack.

The inner frame section 40 may be formed integrally with the blank 10, or may comprise a separate piece that is adhered to blank 10 during assembly of pack 20. For example, Figure 4B illustrates a blank 10 that generally corresponds in shape with the blank of Figure 3 A, and which further includes an inner frame portion 40 depending from the edge 381 of the connector panels 14, 18. The inner frame portion 40 includes a central creased area CRl having a plurality of mutually parallel crease lines. The central creased area CRl divides the frame into two major panels 201 and 202 that form the front of the inner frame 40 when folded into the erected pack 20. The inner frame portion 40 also includes two lateral creased areas CR2, CR2' that are parallel with the central creased area CRl ₃ thereby forming two lateral panels 203 and 204, one on either side of the major panels 201, 202. The two lateral panels 203 and 204 allow the inner frame to be anchored in the assembled pack 20, for example by adhesive.

The inner frame section 40 may also comprise retaining tabs 41 formed in the central creased area CRl. The retaining tabs 41 (shown as a pair in Figure 4A) are operable in the assembled pack 20 to interfere with the inner surface of the lid portion 8 to provide resistance against the inner surface of the lid 8 on opening and closing. Tabs 41 therefore assist in retaining the lid in a closed position.

In one embodiment of an assembled pack 20 made from a blank having an integral inner frame section 40, the whole of the inner frame section 40 is folded relative to connector panel 14 through an angle of 180 degrees about their adjoining edge 381. This leads to overlap of the panels 204, 201, 202, 203 and creased areas CRl, CR2, CR2' of the inner frame section 40 with corresponding panels 14, 11, 12, 13 and creased zones 341, 342, 343 of the blank 10 (see Figure 4C).

Subsequent to folding the inner frame section 40 into contact with the blank 10, the same method steps as described above in relation to assembling the blank 10 into a pack 20 can be used. Depending on the width of panels 14 and 204 (as indicated by the dashed line in Figure 4A), in the assembled pack 20 a marginal area of panel 203 may be sandwiched between panel 13 and panel 14, wherein panel 13 forms an exterior wall of the assembled pack 20.

A similar apparatus/procedure to that shown in Figures 5 and 6 may be used for making the pack 20 from the blank of Figure 4B, except that step S3 may be omitted, assuming that the blank 10 is introduced with the inner frame 40 pre-folded against the blank 10. Alternatively, an additional folding station may be provided to fold the inner frame section 40 relative to the blank 10. The assembly steps at stations S4 to SlO can then remain the same as described above.

In another embodiment, the pack may be made erected "top out". In this arrangement, at station S6, the top end panel 21 may be folded perpendicular to the direction of travel of the arbour. This enables the top panel 21 to be folded more efficiently than trying to fold the panel in the direction of travel of the arbour (folding a large panel or flap in the direction of travel adds to the complexity of the folding process). In this embodiment, the orientation of the arbour may be rotated relative to the direction of travel, so that a triangular corner of the arbour, for example, formed by the edges supporting panel 21 and flap 22, is pointing in the direction of rotation. This allows both panel 21 and flap 22 to be folded in a direction that is at least partly against the direction of travel. (This is to be contrasted with the configuration of Figure 7, where a triangular corner of the arbour 62 is pointing opposite to the direction of rotation).

Figure 6 A illustrates an alternative embodiment of the stations of the arbour carousel during assembly of a prismatic pack of substantially triangular cross-section. The carousel 60 again has twelve stations (Sl -S 12) in which various steps in the assembly of the pack 20 are performed. In Figure 6A, the pack is made "base out", so that the container portion 6 with associated bottom end panel 25 is formed on an outside end 62b of arbour 62 furthest from carousel 60. In Figure 6A, the leading edge of the blank is a free/cut edge of bottom end panel 25.

In station Sl of Figure 6A, the trailing surface of arbour 62 is positioned perpendicular to the direction of rotation. A precut foil wrapper 50 is fed into station Sl parallel to the trailing surface 64 of arbour 62. From station Sl to station S2, foil wrapper 50 is folded F and subsequently overlapped around the outside surface of arbour 62.

From station S2 to S3, foil wrapper end is folded F from the direction of the trailing surface 64 of arbour 62 around arbour 62. At station S3, inner frame 40 is fed parallel to trailing surface 64 of arbour 62 and placed on an inside end 62a of the arbour nearest carousel 60 (since this is a "base out" configuration).

From station S3 to S4, inner frame 40 is partially folded away from the direction of travel. In station S4, diecut blank 110 is fed parallel to the trailing surface 64 of arbour 62. From station S4 to S5 the remaining folding for positioning the inner frame 40 is completed. Also, from station S4 to station S5, diecut blank 110 is folded F and subsequently overlapped around the outer surface of inner frame 40, foil wrapper 50, and arbour 62. (This overlap corresponds to panels 13 and 14 in Figure 2).

From station S5 to S6, end flaps 121 and 125 are folded F. Also from station S5 to station S6, but after end flaps 121 and 125 have been folded, bottom end panel 25 is folded F in the direction of travel to close the bottom end of container portion 6.

Station 10 is where the bundle of product 52 is inserted into the hollow arbour 62 from the remaining open end of the triangular pack 120. Bundle of product 52 is pre-foπned into a substantially triangular shape in order to be inserted. From stations S8 through to S12 a restrictor place 66 (as per Figure 5) restricts movement of the pack and so permits product bundle 52 to be inserted without pushing the pack off the arbour.

When the relevant arbour returns to station Sl, the bundle of product is pushed out of arbour 62 (this is assisted if the arbour is hollow at both ends), and the partially assembled triangular pack is placed on an outlet conveyor 100. At outlet conveyor 100, the remaining portion of the unfinished pack, which includes top end panel 21, top flaps 22 and 121, and foil wrapper 50, are subsequently folded to complete the triangular pack. Upon removal of the pack and product bundle at station Sl, the now emptied arbour begins the assembly process again.

Figures 9 to 14 illustrate examples of blanks 1OA to 1OF in accordance with various other embodiments of the invention. The blanks 1OA to 1OF are suitable for making a triangular pack

(such as shown in Figure 1), although the arrangement of end flaps is different from the blanks 10 previously described.

The blank 1OA of Figure 9 has a generally rectangular section divided by three crease zones extending between the top 31 and bottom 30 edges parallel to side edges 381 and 382. The crease zones correspond to the rounded edges of the pack and divide the blank into the side panels 11 and 15, 12 and 16, and 13 and 17, together with a connecting panel 14 and 18. In the erected pack, the connecting panels 14 and 18 overlap, and adhere to, a marginal zone of corresponding panels 13 and 17.

A cut defines the demarcation line 19 between the lid portion 8 and the container portion 6. The line 19 extends across the blank between panels 11 and 15 and between panels 12 and 16 as for the embodiment of Figure 2. A crease line 28 connecting panels 14 and 18 is aligned with a corresponding crease line 27 between panels 13 and 17 to provide a hinge for the lid. The crease lines 28 and 27 meet the ends of the demarcation line 19.

In the example of Figure 9, the top and bottom triangular panels 21 and 25 are hinged to the panels 17 and 13 respectively, in effect being at opposite ends of the same panel. The top triangular end panel 21 has one flap 23 on one edge thereof and the other edge is free. The bottom triangular end panel 25 has two flaps 24, 26 on respective edges and thus has no free edges.

The blank 1OA may additionally comprise a further flap 22 for engaging the inner surface of the top panel 21 of the lid adjacent its free edge. The top and bottom triangular panels may be offset as indicated by dashed end panel 2511, 2411 and 2611; i.e. the top and bottom panels may be on different side panels.

The pack of Figure 9 may be erected, for example, by:

Folding the flaps 23, 24 and 26 at right angles to their triangular end panels 21 and 25 so that when the flaps 21 and 25 are folded towards the side panels, the flaps can engage the inside surfaces of the side panels.

Folding the triangular end panels 21, 25 to be at right angles to the panel 13.

Folding the main panels 11, 12 and 13 of the blank and the connecting panel 14 around the end panels 21 and 25, such that the already folded flaps 23, 24 and 26 contact their inner surfaces. The flaps 23, 24 and 26 can be glued to their corresponding side panels to fix the triangular form at the end of the pack 20. The connecting panel 14 can overlap the outside (or the inside) surface of a marginal zone of the panel 13. At the overlapping section the connecting panel 14 and the side panel 13 are glued together to fix the triangular form of the pack. (It will be appreciated that the

skilled person will be aware of many other ways of forming pack 20, including using an arbour, if so desired, configured to accommodate the flaps 23, 24, 26).

Figure 10 shows a modification 1OB of the blank of Figure 9. The blank 1OB differs from blank 1OA in that the top panel 21 has a flap 22 on a different edge, and the other edge of the triangular end panel 21 remains free. A flap 23 may be provided on the side panel 15 of the Hd 8. The top and bottom panels may be on the same side panel as shown or on different side panels.

Figure 11 shows another modification 1OC of the blank of Figure 9. The blank 1OC differs from the blank 1OA in that the top triangular end panel 21 has two flaps 23 and 22 on respective edges and the bottom triangular end panel 25 has only one flap 26. A flap 24 may be provided on the side panel 11 of the container 8. The top and bottom panels may be on the same side panel as shown or on different side panels.

Figure 12 shows a modification 1OD of the blank of Figure 11. The blank 1OD differs from the blank 1OC in that the bottom panel 25 has only one flap 24 on a different edge. A flap 26 may be provided on the side panel 12 of the container 6. The top and bottom triangular end panels may be on the same side panel as shown or on different side panels.

Referring to Figure 13, in blank 1OE one triangular end panel, in this example panel 21, has no flaps and the other triangular end panel 25 has two flaps 24 and 26. The edge 31 to which the end panel 21 having no flaps is attached has flaps 22 and 23 for connection to the free edges of the triangular panel 21 when the pack is erected.

Referring to Figure 14, in blank 1OF one triangular end panel, in this example the top end panel 21, has one flap and the other triangular end panel 25, has no flaps. The edge 31 to which the top end panel 21 is attached has a flap 23 for engaging the free edge of the top end panel 21 when the pack 20 is erected. The edge 30 to which the bottom end panel 25 is attached has flaps 26 and 24 for connection to the free edges of the bottom end panel 25 when the pack 20 is erected.

Referring to Figure 15, in other possible modifications the triangular top and bottom end panels 21 and 25 may for example both have only one flap attached to an edge 22, 26 with optionally one flap 23, 24 being provided on each of the top and bottom edges 30 and 31 to engage the otherwise free edge of the triangular panel in the erected pack. In Figure 15, the flaps on the top and bottom end panels 21 and 25 are arranged to engage the same side panel 12, 16. However they may engage with different side panels.

Figure 15 shows an example of a blank 1OG that includes an integral inner frame 40. The frame has panels 141, 111, 121 and 131 corresponding respectively to panels 14, 11, 12 and 13 of the pack. Panels 14 and 141 have the same width. Panel 131 of the frame is of smaller width than side panel 13 of the pack. The panels of the frame are separated by crease zones 3431, 3411, 3421 corresponding to the crease zones 343, 341 and 342 of the pack. When erecting the pack, the inner frame is folded onto the rear surface of the blank of the pack so that the crease zones of the inner frame coincide with the corresponding crease zones of the pack.

In some embodiments, the connecting panels 14 and 18 may be omitted. In this case, the pack may be fixed in the triangular form, for example, by overlapping various flaps on the triangular end panels and/or the edges 30 and 31, such as shown in Figures 9-15, since these can also serve to maintain the overall triangular form of the pack.

Figure 16 shows a top view of an opened pack 20 in its erected state, showing a bundle of cigarettes 52 within a layer of foil 50 inside the pack. The pack 20 of Figure 16 may have been made, for example, from the blanks 1OF or 1OG (Figures 14 and 15). In one embodiment, the pack is erected from a blank using a hollow arbour having the same cross-section as the pack using the following process. Firstly, a foil sheet 50 is applied to and folded around the arbour. Then the inner frame 40 if separate from the blank of the pack is folded around the arbour. In this embodiment, one end of the foil is folded to form a closed end before introducing the blank. The blank having flaps extending from the edge or edges of the end panel is folded end first so that one end of the pack is closed against the arbour before wrapping the remaining panels of the blank around the arbour. A bundle is inserted into the open end of the arbour and then the pack containing the bundle is removed from the arbour such that the open end can be closed.

If the bundle is pre-wrapped in foil, the first stage in the assembly process described above may be omitted. In addition, the blank may include an integral inner frame, which would generally involve one pre-fold of the blank such that corresponding panels of the inner frame and the pack blank coincide before applying to the arbour.

The packs so far described have a cross-sectional shape corresponding to an equilateral triangle. However, the pack may have a cross-section corresponding to any other form of triangle - e.g. isosceles, right-angled, scalene, etc. The edges of the packs may be rounded, sharp, chamfered or any other suitable shape. The pack may be used for holding smoking articles, such as cigarettes or other tobacco or tobacco-replacement products.

A carton for containing one or more triangular packs may be formed from a blank having substantially the same shape as used to make a triangular pack. In other words, multiple triangular packs could be bundled together in a carton which is also triangular in cross-section. The carton could then be formed from a blank such as shown in Figure 2, for example, but on a larger scale, if so desired, in order to accommodate multiple packs.

In conclusion, a variety of particular embodiments have been described in detail herein, but it will be appreciated that this is by way of exemplification only. The skilled person will be aware of many further potential modifications and adaptations that fall within the scope of the claimed invention and its equivalents.