Packaging machine

Abstract: The magazine (8) for the cardboard blanks (C) is located in the input part of the said machine, in line, and outside any higher external profile, and in this magazine the blanks are stacked on edge, with their greatest dimensions in a vertical plane and with their flat faces positioned transversely with respect to the direction of discharge and feed of the said blanks. Means (12-27) cyclically draw the leading blank from the magazine and deposit the said blank on an inclined ascending conveyor (20) located under the path along which the products are stored (1) and grouped (2), the conveyor being provided with pairs of teeth (120) which push the blank from behind and being connected to programmable driving means, to ensure that, when the format of the blanks changes, a predetermined part (S) of each blank is always brought into alignment with the front edge of the group of products (P') formed by the said grouping line. The product storage line is designed for lateral connection to a line (5, 5') for feeding the said products (P) which thus do not interfere with the said blank feed magazine. Downstream from the product grouping line (2), a folder arm (29) carries out the first raising of the rear panel (C4) of a packaging blank which is already carrying a group of products, and then the raising of the front panels (C1, C2) of the following blank, to prepare these panels for the final raising by other means and to prevent the said panels from interfering with each other, while providing a reduced interval between the advancing groups of products and having the consequent objective of increasing the output of the machine.

Description: The invention relates to a packaging machine of the wrap-around type, for wrapping cardboard packaging blanks around preformed groups of products, such as groups of bottles, cans, jars, or other similar containers full of product, which can be converted if necessary to a tray packaging machine, which is characterized in that it has the blank magazine outside, in the input part of and in line with the machine. In what are known as packaging machines, the products to be packaged are supplied from a storage conveyor line, are divided into groups, each consisting of a desired number of rows and lines of products, and then continue, being thus divided into suitably spaced groups, which advance continuously and in alignment with the said storage conveyor line, along which the various operating stations are provided in sequence and carry out: the various operations for inserting a blank under each group of products at the correct time, starting with blanks which are pre-punched in the flat state and taken from a magazine; the operations of raising and folding the panels of the blank, to wrap it around the group of products; the operations of folding and gluing the flaps of the blank, to provide a finished package which encloses the group of products, which is then ready for despatch. Packaging machines of the known type essentially operate according to two different principles. According to a first principle, the blank is inserted into the machine with its greatest dimension orientated in the direction of advance of the groups of products, and according to the other principle the blank is placed transversely. In the first case, the blank magazine is at present placed on one side of the machine and the blanks are usually stacked on a horizontal plane, which limits the load capacity of the magazine, requires complex mechanisms for the cyclical feed of a blank and makes it difficult to maintain the part of the machine on whose side the magazine is fitted. An example of a machine of this type is described in Italian Patent No. 1,174,517 (OCME). In the second case, the blank magazine can be located on one side of the machine, or, more generally, is located under the product conveying and grouping line, with the blanks positioned on edge and on a plane inclined in the longitudinal direction, so that they move by gravity towards the discharge end of the magazine. This second solution is simpler in construction than the first, but also has the drawback of a limited load capacity of the magazine and the difficulty of maintenance of the part of the machine next to the magazine. An example of a machine of this type is described in US Patent No. 5,148,654 (Kisters). In the second type of machine, the closing of the blank is more difficult than in the first type of machine. Document EP 0 786 407 A1 (BAUMER) discloses a packaging machine of the wrap-around type in accordance with the preamble of claim 1, in which the magazine for the cardboard blanks is located at the input part of the said machine, and in alignment with lines or conveyors for storing and grouping the products to be packaged. The invention is intended to provide a packaging machine which could process the blanks in line, with their longitudinal axes in the direction of advance, without having the drawbacks and limits of the known packaging machines of the aforesaid first type, and which would therefore have a large-capacity magazine which was easy to load and to adapt to changes of format, and which would not obstruct parts of the machine which required maintenance with the packaging machine as defined in claim 1. Further characteristics of the invention and the advantages derived therefrom will be made clearer by the following description of a preferred embodiment of the invention, illustrated purely by way of example and without restrictive intent in the figures on the attached sheets of drawings, in which: Fig. 1 shows a perspective diagram of the stages of feeding the blanks and the product and the subsequent stages of forming the cardboard package; Fig. 2 is a lateral elevation of the input part of the improved packaging machine according to the invention; Figs. 3 and 4 are schematic plan views from above of systems for feeding the product before the storage and grouping lines; Fig. 5 is a perspective view of the blank magazine, as seen from the feed side; Fig. 6 is a perspective view of the arm with the suction means which cyclically extracts one blank from the magazine and places it on the subsequent inclined feed conveyor; Figs. 7, 8 and 9 are lateral elevations of the means which close the blanks around the groups of product; Fig. 10 is a perspective view of a tray package which can be formed by the present machine as an alternative to the box package shown in Figures 1, 2 and 5-9. In the perspective diagram of Figure 1, the letter A indicates the input part of the packaging machine, with the blank feed and product feed stations, up to the point where the blank is introduced under a group of products, while B indicates the intermediate and final parts of the same packaging machine, with the stations for folding and closing the blanks around each group of products. The present invention relates to part A and an initial component of part B of the machine. Figures 1, 2 and 5 show that part A of the machine comprises first known aligned horizontal means 1 for conveying and storing the products P placed in single file and in a number of parallel rows, and comprises the subsequent station 2, which is also known, for grouping the groups of products and spacing them apart from each other, this station consisting of a lower motorized input conveyor 102 and a final fixed plane 202, both coplanar with the upstream conveyor 1, and having a conveyor 302 with parallel chains and cross-members for finally pushing the groups of products on to the said plane 202. These conveyor means are followed by other conveyor means 3, 3' and 4 which are also known and which fold the hinged panels and flaps of the blank around the product; these are described more fully below. According to the invention, the products P are fed to the line 1 by a side feed system, for example by a transverse conveyor 5 which, as illustrated in the diagram of Figure 3, can be perpendicular to the said line 1 over the whole of its extension or only over the final portion, the rest being connected with the correct curvature to conveyor branches 105 or 105' parallel to the said line 1 and running in the same direction or in the opposite direction. The products can be transferred from the conveyor 5 to the line 1 by known means, for example by means 6 which stop the products at the end of the conveyor 5 and, at the correct time, by other conveyor means 7 which cyclically place on the line 1 the products which are facing it in the terminal part of the said conveyor 5, these means 7 being driven with an alternating motion or being driven continuously, for example in the same way as the conveyor 302 with the pushing cross-members of the station 2. In a different embodiment, the products can be transferred from the conveyor 5 to the line 1 by means of a fixed channel 205 which is L-shaped in a plan view, indicated by broken lines in the said Figure 3, which deflects the flow of the product from 5 to 1. In another different way, as shown in the variant in Figure 4, the products can be brought to the line 1 by means of an adjacent motorized conveyor 5' which runs in the same direction and by means of a fixed guide channel 205' which is S-shaped in plan view and which deflects the flow of the product from the conveyor 5' to the line 1. In the input part of the machine, upstream from the conveyors 5 or 5' for the lateral feed of the products P and in alignment with the conveyors 1-3-4, a feed magazine 8 is provided for the pre-punched blanks C, which are positioned with their greatest dimension in a vertical plane and which rest with their lower edges on the base plane 108 of the magazine, which is preferably inclined longitudinally with progressive lowering towards the discharge end of the said magazine. The stack of blanks C is pushed from behind by a ballast weight 9 guided so that it slides longitudinally on the said base plane 108, and the said stack is controlled laterally by guiding side members 208, 208' fixed to lower and upper mechanisms 308, 308' for self-centring adjustment, connected together by chains and provided with screws with opposing threads, in a way that is well within the grasp of those skilled in the art, so that the distance between them can be adjusted with changes in the format of the blanks C. Figure 5 shows how one of the guiding side members 208 is shorter at the rear than the other, forming a small lateral end aperture which facilitates the loading operation carried out by the operator, who can make the new blanks bear against the other guiding side member 208', on the base 108 and against the existing stack. It is to be understood that the magazine 8 can be designed differently, with the base plane 108 horizontal and with motorized belts or bands, for conveying the blanks towards the discharge end. At its front or discharge end, the magazine 8 is designed in an essentially known way, with small lateral and base fingers 408, carried by the ends of the bars of the side members 208, 208' and the base 108, which project into the front edge of the magazine to retain the leading blank by its perimeter, while a further finger 408' acts on the midline of the upper horizontal side of the said leading blank and is carried by a cross-member 10 which has a flared profile for the top of the stack, and which is fitted in such a way that its height can be adjusted on a cross-member 11 which is, for example, fixed to the side members 111 of Figure 5. If the blanks C are designed to form a box for the total enclosure of the group of products, the horizontal closing panel F of the box is preferably orientated downwards and is in contact with the base plane 108 of the magazine 8 (Fig. 1). A set of suction cups 12 operates at the front end of the magazine 8, these cups being fitted, with allowance for adjustment of their positions with respect to each other so that blanks of different formats can be correctly gripped, on a structure 13 fixed on a shaft 14 which is parallel to the return shafts of the conveyors 1 and of the other conveyors described above, and which is held rotatably at one end by a perpendicular arm 15 located laterally with respect to the overall dimensions in plan of the blanks C and having its lower end fitted rotatably on a fixed shaft 16 which is parallel to the said shaft 14, and on which is keyed a sprocket or toothed pulley 17 which, by means of a chain or toothed belt 18, is connected to a sprocket or toothed pulley 19 keyed on the said shaft 14. The transmission ratio of the sprockets 17, 19 is such that, as shown in Figures 1 and 2, the structure 13 with the suction cups 12 moves, as a result of the oscillation of the arm 15, from the position in which the leading blank of the magazine 8 is gripped, as shown by the solid line, to the position in which the said blank is released onto an inclined conveyor 20, formed by a pair of parallel chains with corresponding pushing teeth 120, running around the end sprockets on the shafts 21, 21' parallel to those of the upper conveyors 1 and others, and which forms a link between the magazine 8 and the small gap G (Figs. 2 and 7) located between the terminal part of the fixed plane 202 of the station 2 and the initial part of the conveyor 3, through which the packaging blank must be inserted at the correct time under the group of products P' which leaves the said station 2. When the blank is deposited on the conveyor 20, a projection 22 is provided behind the said blank, in the midline of the conveyor 20, and is fixed to the frame of this conveyor, to retain the said blank when it is released by the suction cups 12, before it reaches a facing pair of propelling teeth 120 of the said conveyor 20. It is clear from the sequence shown in Figure 1 that the blank is initially extracted from the magazine 8 by its lower part which therefore precedes the blank during the transfer onto the conveyor 20, by a movement already known in the prior art, which, among other considerations, prevents the occurrence of aerodynamic loading on the extracted blank, which is thus handled carefully and remains correctly spread out. It is to be understood that the rotary movement of the shaft 14 with respect to the arm 15 can be achieved by means different from the means 17, 18 and 19, for example by a system of levers forming an articulated quadrilateral with one fixed side. The arm 15 is, for example, made to oscillate in the requisite way by the pivoting at 23 of its extension 115 on a link 24 pivoted at 25 on a crank 26 which rotates on a shaft 27 parallel to that of the conveyors 1 and synchronized in a known way with the drive means of the station 2 and of the machine in general, in such a way that, whenever a group of products P' leaves the station 2, a blank leaves the conveyor 20 and another blank moves on to it. It is to be understood that the arm 15 can be made to oscillate by means other than the aforesaid ones, for example by a geared motor, by a hydraulic cylinder and piston unit, or by an electrical actuator of the screw and nut type. However, the conveyor 20 is operated by an electric motor, which is not illustrated, of the type with electronic speed and phase control, connected by its electrical shaft to the driving means of the station 2, in such a way that it can be remotely programmed when the format of the blanks C changes, to ensure that a predetermined point of each blank, for example the transverse median hinge S of each blank which leaves after the station 2, is always aligned with the front end of the group of products P' which leaves this station (Figs. 1, 2 and 9). Additionally, the speed of the conveyor 20 is such, with respect to that of the station 2 and the subsequent conveyors 3, 3', 4, that the pushing teeth 120 do not interfere with the fed blank during their travel in a curved path around the shaft 21'. Immediately downstream from the station 2 (Figs. 2 and 7), in the midline of the initial part of the conveyor 3, there is an arm 29, of suitable length and preferably curved upwards, pivoted at 28 parallel to the axes of the said conveyor, this arm having its end nearer the pivot hinged on a cyclical oscillating means 30 consisting, for example, of a hydraulic jack, pivoted at 31 on the fixed frame of the machine. The arm 29 is normally in the low position so that it does not interfere with the blank carrying the group of products P' which is travelling on the composite conveyor 3, 3' and which is directed towards the conveyor 4. As soon as this blank, carrying the product P', has passed beyond the arm 29, and before any subsequent blank which may be fed by the conveyor 20 comes to bear on the arm, the arm 29 is raised as shown in the sequence of Figures 7, 8 and 9, to raise the rear panel C4 of the downstream blank and the set of front panels C1, C2 of the upstream blank, before the known operation of a finger M3' of the conveyor 3' which brings the said panel C4 to a vertical position and the known operation of a finger M3 of the conveyor 3 which brings the set of panels C1, C2 to a vertical position. The folder arm 29 returns to its lower rest position in synchronization with the operation of the finger M3. Clearly, the presence of the folder arm 29 makes it possible to reduce the interval between the advancing packages of products, and thus to increase the output of the machine for a given speed of advance of the packages. When the vertical panel C1 of a blank reaches the point of interaction with the conveyor 4, it is first made to rotate downwards by known means operating upstream from this conveyor and shown schematically in Figure 8 by the arrow 32, which also place a correct quantity of adhesive on the closing panel F, after which the panel C1 is held down by the interaction with the conveyor 4 which has leading fingers M4 positioned before C1 and in contact with C2, and has subsequent fingers M4' which make the panel F rotate downwards and fix it with the adhesive to the rear panel C4. During the movement between the conveyors 3-3' and 4, known means (not illustrated) close the lateral flaps indicated by CL in Figure 1 and fix them together with adhesive.

Claims: Packaging machine of the wrap-around type in which a magazine (8) for cardboard blanks (C) is located at the input part of the said machine, and in alignment with lines or conveyors (1, 3, 4) for storing and grouping the products (P) to be packaged, characterized in that the said magazine (8) is located outside any higher external profile, and in this magazine the blanks are stacked on edge, with their greatest dimensions in a vertical plane and with their flat faces positioned transversely with respect to the direction of discharge and feed of the said blanks, means (12-27) being provided to cyclically draw the leading blank from the magazine and deposit the said blank on an inclined ascending conveyor (20) located under the path along which the products are stored (1) and grouped (2), the conveyor being provided with pairs of teeth (120) which push the blank from behind and being connected to programmable driving means, to ensure that, when the format of the blanks changes, a predetermined part (S) of each blank is always brought into alignment with the front edge of the group of products (P') formed by the said grouping line, the product storage line (1) being designed for lateral connection to a line (5, 5') for feeding the said products (P) which thus do not interfere with the said blank feed magazine. Machine according to Claim 1, in which the lateral line for feeding the products to the storage line (1) can comprise a conveyor (5') adjacent to the said line, running in the same direction, and comprising a fixed guide channel (205') which is S-shaped in plan view and which deflects the flow of the products from the said lateral conveyor (5') to the said storage line (1). Machine according to Claim 1, in which the line for feeding the products laterally to the storage line (1) can be an abutting transverse conveyor line (5) and the products can be transferred from one line to the other by means of a fixed deflecting channel (205) which is L-shaped in plan view, with a rounded angle area, or by the use of means (6) which stop the flow of the products on the line (5) and means (7) which insert transversely into the storage line (1) the products which have been brought up to it on the upstream line. Machine according to Claim 1, in which the blank magazine (8) is provided with a horizontal base plane (108) and with motorized conveyors for advancing the blanks, or is inclined longitudinally downwards in the direction of the discharge end, in such a way that the blanks are advanced towards this end by gravity and by the thrust exerted on the rear end of the stack by a ballast weight (9) which slides in a longitudinally guided way on the said base plane, the said magazine being provided with lateral guiding and containing side members (208, 208') fixed to lower and upper self-centring adjustment mechanisms (308, 308'), interconnected by positive transmissions of motion, of the sprocket and chain type for example, and provided with screws having opposing threads so that their spacing from each other can be adjusted as the format of the blanks used is changed, by means of a centralized control system, the discharge end of the magazine being provided with lateral and base fingers (408) which are integral with the said side members and with the base plane, and which project into the said end to retain the leading blank by its perimeter, and at least one further finger (408') acts in the centre of the upper horizontal border of the leading blank and is supported by a cross-member (10) with a flared profile for the top of the stack of blanks, carried by a fixed cross-member (11) whose height can be adjusted as the format of the blanks changes. Machine according to Claim 1, in which one of the guiding and containing side members (208) of the blank magazine is shorter at the rear than the other to facilitate loading by lateral input of the blanks. Machine according to Claim 1, in which the inclined conveyor (20) for transferring the blanks from the feed magazine (8) to the positioning outlet downstream from a product grouping station (2) consists of a pair of parallel chains with corresponding pushing teeth (120) with fixed lateral guiding and containment means for the blank, and is driven by an electric motor with electronic speed and phase control, programmable by means of the machine control panel so that, when the format of the trays is changed, the predetermined hinged areas (S) of their panels always meet the front ends of the groups of products to be packaged. Machine according to Claim 6, characterized in that there is provided, in the initial, lower and median part of the inclined conveyor (20) which feeds the blanks downstream from the product grouping station, a projection (22) fixed to the frame of the said conveyor, against which the rear end of the blank extracted from the magazine is held while waiting to be engaged by the pushing teeth (120) of the said inclined conveyor (20). Machine according to Claim 1, in which the means which carry out the cyclical extraction of a blank from the discharge end of the magazine (8) and deposit it on the inclined feed conveyor (20) comprise a composite adjustable structure (13), with an appropriate number of coplanar suction cups (12), which is integral with a shaft (14) which has one end mounted rotatably and at a right angle on the end of an arm (15) positioned at the side of the said conveyor (20) and has its other end mounted rotatably on a shaft (16), for example a fixed shaft, which is positioned at the initial low part of the said conveyor (20) and which is connected to the said shaft (14) which carries the structure with the suction cups (12) by means of a positive motion transmission, for example one of the type having sprockets or toothed pulleys (17) and a chain or toothed belt (18), or by a motion transmission in the form of an articulated quadrilateral, with one fixed side, the whole being arranged in such a way that, as a result of the oscillation of the arm (15), the said suction cups (12) are made to extract the leading blank from the magazine with its lower edge foremost, and are then made to move this edge forward until the blank is fully extracted from the retaining fingers (408, 408') and is deposited on the said inclined conveyor (20) with the previously visible surface of the blank facing upwards. Machine according to Claim 8, in which the oscillating arm (15) which carries the structure with the suction cups (12) is made to carry out its oscillating movement by any suitable means, for example a link and crank system (24, 26) with the crank keyed on a shaft (27) which rotates in phase with the product grouping station (2). Machine according to Claim 1, in which there is provided, immediately downstream from a product grouping station (2), an oscillating arm (29) which is normally in the low position and is orientated away from the said station, so that the blank carrying the group of products can move freely over it, this being made to be raised, as soon as the said blank has passed beyond it, by an appropriate actuator (30) to raise the rear panel (C4) of the said blank and to raise the set of the first two panels (C1, C2) of the following blank which is about to leave the said grouping station (2), in such a way that the said panels are prevented from interfering with each other and are prepared for the operation of the front and rear fingers (M3, M3') of the known composite lower conveyor (3, 3') which, in conjunction with a corresponding upper conveyor (4) which is also known and is provided with corresponding front and rear fingers (M4, M4'), close all the panels (C1-C4) of the packaging blank around the product and fold the final closing panel (F), the whole being additionally designed to reduce the interval between the groups of advancing products and thus to increase the output of the machine for a given speed of advance of the said groups of products.

Inventors: ORSI MARIO, ORSI, MARIO
Applicants: PRASMATIC S R L, PRASMATIC S.R.L.
Application year: 2001
Main classification: B65B21
IPC codes: B65B21