A method for manufacturing a preformed sheet intended to be folded to a carton and an apparatus for carrying out the method

Abstract: A method for producing cartons, boxes or the like from a continuous sheet (1'), the carton comprising a substantially tubular, not necessarily cylindrical carton part which in cross-section has at least three sides and is formed with the aid of a continuous row of sequentially disposed carton portions which form side parts, and further comprising flap parts at at least one of both ends of the carton part at at least certain of the side parts, the tubular carton part being closed by the flap parts. The method is particularly characterized in that a sheet (1') of requisite shape is produced with the aid of a fixture (5) having a longitudinal extension which corresponds to the longitudinal extension of the tubular carton part and a cross-sectional outer profile which corresponds to the cross-sectional outer profile of the tubular carton part. An edge part (8) of a sheet of requisite size is attached to the fixture (8), preferably in connection with a longitudinally extending corner part (9) of the fixture, this corner part (9) forming a demarcation line between two mutually adjacent side parts, and where the sheet is folded, wrapped, around the fixture to form the tubular carton part and flap parts which are a continuation of the carton part. The fixture can be used as a template when it is necessary to remove excess parts of the sheet attached to the fixture. The invention also relates to apparatus for carrying out the method.

Description: The present invention relates to a method for manufacturing a preformed sheet, which is intended to be folded to a carton, from a, where appropriate, larger continuous sheet blank, said carton comprising a substantially tubular carton part which in cross section exhibits at least three sides and which is constructed with the aid of a continuous row of mutually sequential carton portions which form side parts of the carton, and further comprises flap parts located at at least one of the two ends of the carton part at at least certain of the side parts, said flap parts functioning to close the tubular carton part. The invention also relates to an apparatus for carrying out the method. Cartons of the aforesaid kind are typically produced by high-capacity mechanical punching and creasing processes. This requires large investments in machines, tools, etc., these high investments being unacceptable in the case of low capacity requirements. The present invention relates to a method and apparatus for the low-capacity production of such cartons in an efficient manner and at low costs. The invention can be applied with both manual and semi-manual productions of cartons of a given size with a starting point from cartons of larger sizes. DE-A- 1 901 380 discloses the use of a fixture for automatically forming a carton. The carton is formed by wrapping a continuous sheet around the fixture, folding from the fixture longitudinally projecting portions of the wrapped sheet in transverse directions to form a bottom part of the carton and securing the folded bottom portions to each other, whereafter the thus manufactured carton is removed from the fixture. With such a fixture a sheet intended to be folded to a carton having flap parts separated from each other can not be produced. The method according to the invention is particularly characterized by producing a sheet of requisite configuration with the aid of a fixture having a central part having a longitudinal extension which corresponds to the longitudinal extension of the tubular carton part and two support parts projecting substantially in the aforesaid longitudinal direction from the respective ends of the central part of the fixture, said fixture having a cross-sectional outer profile which corresponds to the cross-sectional outer profile of the tubular carton part; by mounting the abovementioned continuous sheet blank on the fixture with an edge part of said sheet blank being located contiguous with a longitudinally extending corner part of the fixture, said corner part forming a demarcation line between two mutually adjacent side parts; folding, wrapping said sheet blank around the fixture to form said tubular carton part and the flap parts forming a continuation of said carton part; and by removing excessive parts of said sheet blank mounted on the fixture when necessary and separating adjacent flap parts from each other by cutting, while the sheet is wrapped around the fixture. The invention also relates to an apparatus for carrying out said method particularly characterized by a fixture comprising a central part having a longitudinal extension which corresponds to the longitudinal extension of the tubular carton part and two support parts projecting substantially in the aforesaid longitudinal direction from the respective ends of the central part of the fixture, said fixture having a cross-sectional outer profile which corresponds to the cross-sectional outer profile of the tubular carton part; said fixture includes attachment devices for receiving an edge part of a sheet blank, said attachment devices being located adjacent a longitudinally extending corner part of the fixture, said corner part forming a demarcation between two mutually adjacent side parts, and wherein the fixture is configured to form a template or the like for separating adjacent flaps from each other and for, when necessary, removing excess parts of a sheet blank wrapped around the fixture. Particular embodiments of the method and the apparatus according to the present invention are set out in the dependent claims. The invention will now be described in more detail with reference to exemplifying embodiments thereof illustrated in the accompanying drawings; in which Figure 1 illustrates schematically a first embodiment of an inventive fixture, seen transversely to the longitudinal axis of the fixture; Figure 2 illustrates the fixture of Figure 1, seen from the right of said Figure; Figure 3 illustrates a sheet produced with the aid of and in accordance with a fixture substantially of the kind illustrated in Figures 1 and 2; Figure 4 is a perspective view of a carton or box produced from a sheet substantially according to Figure 3; Figure 5 illustrates schematically a knife arrangement for producing flap parts of a sheet, and illustrates the fixture as seen in Figure 2; Figure 6 illustrates schematically the arrangement shown in Figure 5, seen from the left in said Figure; and Figure 7 is a schematic, central longitudinal sectional view of an embodiment of an inventive fixture provided with collapsible support parts. In Figure 4, the reference numeral 1 identifies a carton produced in accordance with the invention, while in Figure 3 the reference numeral 1' identifies a continuous, finished sheet produced from a sheet blank having a size which includes at least said finished sheet. The carton 1 comprises a substantially tubular, not necessarily cylindrical, carton part 2, which in the illustrated embodiment has a substantially rectangular outer cross-sectional profile, flap parts 3 located preferably at each of the two ends of said carton part, these flap parts functioning to close the tubular carton part. In cross-section, the illustrated carton part is constructed from a continuous row of sequentially disposed carton members which form side parts 4, Figure 3. In Figures 1 and 2, the reference numeral 5 identifies a fixture which has a longitudinal extension that corresponds to the longitudinal extension of the tubular carton part, and a cross-sectional outer profile which corresponds substantially to the cross-sectional outer profile of the tubular carton part 2. The illustrated fixture 5 includes attachment devices 6 in the form of elongated retaining slots 7 which are intended to receive an edge part 8 of a sheet blank, preferably contiguous with an elongated corner part 9 thereof, said corner part 9 forming a demarcation part between two mutually adjacent side parts 4; a sheet blank is intended to be folded, wrapped, around the fixture, Figure 2, to form the tubular carton part 2 and also flap parts as a continuation of the carton part. The fixture is also intended to form a template to facilitate remova-excessive parts of a sheet blank mounted on the fixture, when necessary. An edge part 8 of a sheet blank is intended to be inserted into said retaining slot 7 and folded and retained, such as to form from said edge part 8 a securing flap 8' by means of which, when constructed, the tubular carton part is held together in a known manner. According to one preferred embodiment, illustrated in Figure 2, the slot 7 has a predetermined depth to which the edge part 8 can be inserted, the depth of said slot 7 functioning to determine the length of the securing flap transversely to the longitudinal direction, i.e. in the circumferential direction of the tubular carton part. Projecting substantially in the aforesaid longitudinal direction, from the part 5', i.e. the central part 5', of the fixture, said part corresponding to the tubular carton part 2, are support parts 5'' which form cutting slits 9' which enable the fixture to be used as a template or the like when forming said flap parts 3 with the aid of cuts 3' made substantially in the longitudinal direction of the fixture. According to one preferred embodiment, the fixture includes externally mounted strips 10 which extend substantially transversely to said longitudinal direction at the ends of the central part 5', said strips 10 functioning to produce bending lines 11, Figure 3, in the junction between the tubular carton part and the flap parts, primarily by being pressed into the sheet blank. In the case of the embodiment of the fixture illustrated primarily in Figures 1 and 2, the fixture comprises a substantially tubular, but not necessarily cylindrical, body having a central part 5' which functions to form the tubular carton part 2, and two end parts 12 which adjoin the central part 5'. The end parts 12 form support parts which function to form flap parts and which include requisite cutting slots or slits, in the illustrated case corner-located slits, which is typical with such apparatus. The body of the fixture includes two, internally located end walls 13, where one end wall is located at the junction between the central part 5' and respective end parts 12. The end walls have a stiffening and retaining effect. As with the illustrated case, the retaining slot 7 can be given a predetermined depth, by providing a recess 7' in each end wall, as seen from Figure 2. According to another embodiment of the fixture, the fixture can be rotated about a longitudinal axle or shaft. As illustrated in Figures 5 and 6 in the case of this embodiment, an axle or shaft 14 extends at least from one end wall 13 or the like and is connected to means (not shown) for rotation of the fixture. According to a further embodiment, a knife arrangement 15 or the like is provided for the purpose of forming said flap parts as the fixture is rotated. In the case of the illustrated embodiment, a sleeve 17 carrying knife means is arranged to move on the axle or shaft 14 and is held substantially against rotation on the shaft 14 by means of a wedge-like latching arrangement 16, said knife means being intended to move in the cutting slits. Figure 7 illustrates an embodiment of the inventive fixture in which the support parts can be folded or collapsed to and extended from an end-wall position, as indicated by the arrows 19. In this case, when the arrangement includes four support parts 5'' at respective ends of the fixture, the support parts are preferably capable of being collapsed and extended in pairs. Embodiments are conceivable in which only two mutually opposing support parts 5'' are provided at each end of the fixture. In this case, cutting slits are formed by omitting two side parts, cutting of the sheet being effected along the longitudinal edges of said support parts. In the case of embodiments which include foldable support parts, no strips 10 are required for producing folding lines, since folding of the flap parts 3 can be effected along the wall edge 20 of the central part. The support parts 5'' are preferably capable of being fixed in their respective end-wall positions, with the aid of suitable latching devices, and optionally of being returned from the end-wall position under the action of spring forces 21, as illustrated in Figure 7. The manner in which the inventive apparatus works, and also the working steps of the inventive method, will be understood in all essentials from the aforegoing. Thus, one edge part of a sheet blank, which may consist of a piece of a used, larger carton or box, is appropriately attached to the fixture and the sheet blank rotated so as to wrap around the fixture. Protruding parts of the sheet blank are cut away and flap parts are formed by means of substantially longitudinally extending cuts. A sheet blank mounted on the fixture is shown in broken lines in Figure 2. In the case of the embodiment illustrated in Figure 7, a carton or box 1 can be produced essentially on the fixture. In this case, cuts are made along the lines 3'' to provide flap parts 3, whereafter the flap parts at one end of the fixture, and also the end-wall parts, are folded to an end-wall position in order to close one end of the carton or box, whereafter said parts are secured permanently with the aid of adhesive tape or the like. The flap parts at the other end are folded in a corresponding manner, although closure of the box or carton is not made permanent and the flap parts, and suitably also the support parts, can be re-extended to an open position, whereafter the fixture, possibly with the aid of an internal handle 22, is lifted from the carton or box thus constructed. It will be understood from the aforegoing that the method and apparatus according to the invention provide a solution to the aforesaid problem of producing cartons, boxes and the like in a rational manner at low cost. Although the invention has been described with reference to illustrative embodiments thereof, it will be understood that other embodiments and minor modifications to those embodiments shown are conceivable, without departing from the concept of the invention. For instance, cartons in which the tubular carton part 2 comprises a desired number of side parts 4, for instance three such parts, can be produced, by appropriate configuration of the cross-sectional outer profile of the central part of the fixture. Furthermore, it is conceivable to provide flap parts 3 solely at one end of the carton part 2. It is also conceivable provide flap parts solely at certain side parts. Those cuts 3'' by means of which the flap parts are formed can, of course, be produced in a manner different to that described. For instance, the cuts can be made manually with the aid of a knife, such as the knife 18 shown in Figure 1. The invention shall not therefore be considered as limited to the aforedescribed and illustrated embodiments, since modifications can be made within the scope of the following Claims.

Claims: A method for manufacturing a preformed sheet, which is intended to be folded to a carton, from a, where appropriate, larger continuous sheet, said carton comprising a substantially tubular carton part which in cross section exhibits at least three sides and which is constructed with the aid of a continuous row of mutually sequential carton portions which form side parts of the carton, and further comprises flap parts located at at least one of the two ends of the carton part at at least certain of the side parts, said flap parts functioning to close the tubular carton part, characterized by producing a sheet (1') of requisite configuration with the aid of a fixture (5) having a central part (5') having a longitudinal extension which corresponds to the longitudinal extension of the tubular carton part (2) and two support parts (5'') projecting substantially in the aforesaid longitudinal direction from the respective ends of the central part (5') of the fixture (5), said fixture having a cross-sectional outer profile which corresponds to the cross-sectional outer profile of the tubular carton part (2); by mounting the abovementioned continuous sheet on the fixture (5) with an edge part (8) of said sheet being located contiguous with a longitudinally extending corner part (9) of the fixture (5), said corner part (9) forming a demarcation line between two mutually adjacent side parts (4); folding, wrapping said sheet around the fixture (5) to form said tubular carton part (2) and the flap parts (3) forming a continuation of said carton part; and by removing excessive parts of said sheet mounted on the fixture when necessary and separating adjacent flap parts (3) from each other by cutting, while the sheet is wrapped around the fixture. A method according to Claim 1, characterized in that said edge part (8) is inserted into a locking slot (7) in the fixture and is retained by said locking slot while folding the sheet around said fixture, to form a securing flap (8') by means of which the tubular carton part can be held together. A method according to Claim 1 or 2, characterized in that the flap parts (3) are formed by cuts extending substantially in the longitudinal direction of the fixture, and in that the cuts are made with the aid of cutting slots (3') which extend substantially in said longitudinal direction and which enable the fixture to be used as a template. A method according to Claim 1, 2 or 3, characterized in that folding lines (11) are formed in the junctions between the tubular carton part (2) and the flap parts (3) with the aid of strips (10) mounted externally on the fixtures and extending substantially transversely to said longitudinal direction. A method according to Claim 1, 2, 3 or 4, characterized in that the fixture is driven for rotation about a longitudinal axis, such as to enable the sheet to be wound around the fixture. A method according to Claim 1, 2, 3, 4 or 5, characterized in that substantially longitudinal cuts (3') forming said flap parts (3) are made with the aid of driven knife means (15). A method according to Claim 1, 2, 3, 4, 5 or 6, characterized in that the flap parts (3) are folded to an end-wall position, which corresponds to a position in which the tubular carton part is closed, along the end-wall edges (20) of the tubular carton part, and in that all support parts forming templates in the formation of said flap parts are folded to an end-wall position. A method according to any one of the preceding Claims, characterized by producing a sheet (1') for the production of a substantially parallelepipedic carton (1) with the aid of the fixture (5), that part (5') of said fixture which is intended to form the substantially tubular carton part (2) having a substantially rectangular or square cross-sectional shape. An apparatus for manufacturing a sheet, which is intended to be folded to a carton, from a, where appropriate, larger continuous sheet, said carton comprising a substantially tubular carton part which in cross section exhibits at least three sides and which is constructed with the aid of a continuous row of mutually sequential carton portions which form side parts of the carton, and further comprises flap parts located at at least one of the two ends of the carton part at at least certain of the side parts, said flap parts functioning to close the tubular carton part, characteri zed by a fixture (5) comprising a central part (5') having a longitudinal extension which corresponds to the longitudinal extension of the tubular carton part (2) and two support parts (5'') projecting substantially in the aforesaid longitudinal direction from the respective ends of the central part (5') of the fixture (5), said fixture having a cross-sectional outer profile which corresponds to the cross-sectional outer profile of the tubular carton part (2); said fixture includes attachment devices (6) for receiving an edge part (8) of a sheet blank, said attachment devices being located adjacent a longitudinally extending corner part (9) of the fixture, said corner part forming a demarcation between two mutually adjacent side parts (4), and wherein the fixture (5) is configured to form a template or the like for separating adjacent flaps (3) from each other and for, when necessary, removing excess parts of a sheet blank wrapped around the fixture. Apparatus according to Claim 9, characterized in that the fixture includes a sheet-retaining slot (7) which extends longitudinally along a corner part (9) and in which said edge part (8) of a sheet blank is intended to be inserted so as to retain said edge part while folding the sheet blank around said fixture, the intention being to form a securing flap (8') of the sheet blank by means of which the tubular carton part (2) is held together. Apparatus according to Claim 10, characterized in that the slot (7) has a predetermined depth to which said edge part (8) can be inserted, the depth of the slot (7) determining the length of the securing flap (8') transversely to the longitudinal direction and therewith in the circumferential direction of the tubular carton part. Apparatus according to Claim 9, 10 or 11, characterized in that said support parts (5'') form cutting slits (3') which enable the fixture to be used as a template or the like when forming said flap parts (3) with the aid of cuts (3'') made substantially in the longitudinal direction of the fixture. Apparatus according to Claim 9, 10, 11 or 12, characterized in that said support parts (5'') can be folded to an end-wall position, wherein the flap parts (3) are intended to be folded to an end-wall position along the wall edges (20) of the tubular carton part so as to form folding creases along which the tubular carton part can be closed. Apparatus according to Claim 9, 10, 11, 12 or 13, characterized in that the fixture includes externally mounted strips (10) which extend substantially transversely to said longitudinal direction at the ends of the part (5') of the fixture corresponding to the tubular carton part, said strips (10) functioning to provide folding lines (11) in the junction between the tubular carton part and the flap parts. Apparatus according to Claim 9, 10, 11, 12, 13 or 14, characterized in that the fixture can be driven for rotation about a longitudinal axle. Apparatus according to Claim 9, 10, 11, 12, 13, 14 or 15, characterized by driven knife means (15) which are operative to make substantially elongated cuts which form flap parts. Apparatus according to Claim 9, 10, 11, 12, 13, 14, 15 or 16, characterized in that the part (5') of the fixture by means of which the substantially tubular carton part is formed has a substantially rectangular or square cross-sectional outer profile. Apparatus according to Claim 9, 10, 11, 12, 13, 14, 15, 16 or 17, characterized in that the fixture includes a substantially tubular body having a central part (5') which is intended to form said tubular carton part, and the support parts (5'') which connect with the central part and which are intended to form flap parts include requisite slits (3'), such as corner-part based slits. Apparatus according to Claim 18, characterized in that the body includes two internal end-wall parts (13), where one end-wall part is located at the junction between the central part (5') and respective support parts (5'').

Inventors: JONDELIUS BJOERN, JONDELIUS, BJOERN, Jondelius, Björn
Applicants: JONDELIUS BJOERN, JONDELIUS, BJOERN
Application year: 1990
Main classification: B31B1
IPC codes: B31B3