LINE FOR THE PRODUCTION OF COVERED CARDBOARD BOXES

Abstract

A line and method for the production of covered cardboard boxes are disclosed. The line includes a conveyor unit including a belt and a conveyor actuator that drives the belt intermittently in an alternating sequence of movements and stops. A feed unit individually feeds covering blanks from a reservoir to the conveyor unit in a sequence of feed instants. An erecting machine folds box blanks into corresponding boxes. A positioner individually positions the boxes from the erecting machine, in alignment on corresponding covering blanks disposed on the belt of the conveyor unit. A gluer spreads glue on one face of the covering blanks. A covering machine folds the covering blanks into contact with their respective boxes to cover the boxes. A control unit connected to the feed unit adjustably sets a phase displacement of the feed instants relative to the sequence of stops of the belt.

Claims

1. A method of producing covered cardboard boxes, the method comprising: transporting a plurality of covering blanks from a loading position to an unloading position, by means of a conveyor unit including a belt driven intermittently by a conveyor actuator in a sequence of movements, starting at respective movement instants and alternated with corresponding stops; picking up the covering blanks and feeding them to the loading position of the belt by means of a feed unit, in a sequence of feed instants corresponding to the sequence of movements; receiving box blanks in an erecting machine and folding the box blanks to form corresponding boxes; positioning each box in alignment on a corresponding covering blank disposed on the belt, at a coupling position interposed between the loading position and the unloading position; spreading glue on one face of the covering blanks which will come into contact with a corresponding surface of the boxes to be covered; transporting the boxes coupled to the respective covering blanks as far as the unloading position by means of the conveyor unit; feeding the boxes coupled to the respective covering blanks to a covering machine which folds each covering blank into contact with a respective box in such a way as to cover the respective box; adjustably setting, through a control unit, a phase displacement of the feed instants relative to corresponding movement instants of the belt, wherein the control unit adjusts the phase displacement of the feed instants relative to the sequence of stops of the belt; and with the control unit, receiving format data representing a format of the covering blanks, and adjusting the phase displacement of the feed instants relative to the sequence of stops of the belt.

2. The method according to claim 1, wherein the control unit varies the sequence of movements and the stops of the belt.

3. The method according to claim 1, wherein the control unit sets the sequence of movements and the stops of the belt as a function of the format data.

4. The method according to claim 1, wherein the line comprises a feed actuator, separate from the conveyor actuator and wherein feeding the covering blanks is performed by means of the feed unit driven by the feed actuator.

5. The method according to claim 4, wherein the control unit activates the feed actuator and the conveyor actuator in a synchronous and phase-displaced manner as a function of the phase displacement of the feed instants relative to the corresponding stops of the belt.

6. The method according to claim 4, wherein the control unit activates the feed actuator in the sequence of feed instants, which are temporally located in respective time intervals during which the belt is in motion.

7. The method according to claim 1, wherein feeding the covering blanks to the loading position of the belt is performed with the belt of the conveyor unit in motion.

8. The method according to claim 1, further comprising: with a first suction zone of the belt, adjacent to the feed unit, applying a first suction force on the covering blanks; and with a second suction zone of the belt, spaced from the feed unit, applying a second suction force on the covering blanks, wherein the second suction force is smaller than the first suction force.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0094] This and other features will become more apparent from the following description of a preferred embodiment, illustrated by way of non-limiting example in the accompanying drawings, in which:

[0095] FIG. 1 is a plan view of a line for the production of covered cardboard boxes;

[0096] FIG. 1A schematically represents a plan view of the line of FIG. 1;

[0097] FIG. 2 is a side view of a feed unit of the line of FIG. 1;

[0098] FIGS. 2A and 2B schematically illustrate two embodiments of the feed unit of FIG. 2;

[0099] FIG. 3 schematically illustrates the connections of a control unit of the line of FIG. 1;

[0100] FIG. 4 schematically illustrates the steps of a method for the production of covered cardboard boxes;

[0101] FIG. 5 schematically illustrates some of the steps of the method of FIG. 4;

[0102] FIG. 6A schematically illustrates a time graph of the operation of the conveyor and feed units of the line of FIG. 1, in an embodiment in which the feed unit is phase-advanced relative to the conveyor unit;

[0103] FIG. 6B schematically illustrates the line of FIG. 1 at the instant of time, labelled “t.sub.0” in FIG. 6A, where “t.sub.0” indicates a starting instant at which there are still no blanks on the belt;

[0104] FIG. 6C schematically illustrates the line of FIG. 1 at the instant of time, labelled “ts-s-T.sub.f” in FIG. 6A;

[0105] FIG. 6D schematically illustrates the line of FIG. 1 at the instant of time, labelled “ts-s” in FIG. 6A;

[0106] FIG. 6E schematically illustrates the line of FIG. 1 at the instant of time, labelled “ts” in FIG. 6A;

[0107] FIG. 6F schematically illustrates the line of FIG. 1 at the instant of time, labelled “t.sub.r” in FIG. 6A, where “t.sub.r” indicates an instant of time in which the line is working in steady state;

[0108] FIG. 7A schematically illustrates a time graph of the operation of the conveyor and feed units of the line of FIG. 1, in an embodiment in which the feed unit is phase-delayed relative to the conveyor unit;

[0109] FIG. 7B schematically illustrates the line of FIG. 1 at the instant of time, labelled “t.sub.0” in FIG. 7A, where “t.sub.0” indicates a starting instant at which there are still no blanks on the belt;

[0110] FIG. 7C schematically illustrates the line of FIG. 1 at the instant of time, labelled “t.sub.0+s” in FIG. 7A;

[0111] FIG. 7D schematically illustrates the line of FIG. 1 at the instant of time, labelled “t.sub.0+s+T.sub.f” in FIG. 7A;

[0112] FIG. 7E schematically illustrates the line of FIG. 1 at the instant of time, labelled “ts” in FIG. 7A;

[0113] FIG. 7F schematically illustrates the line of FIG. 1 at the instant of time, labelled “t.sub.r” in FIG. 7A, where “t.sub.r” indicates an instant of time in which line operation is at steady state.

DETAILED DESCRIPTION

[0114] With reference to the drawings listed above, the numeral 1 denotes a line 1 for the production of covered cardboard boxes.

[0115] The line 1 for the production of covered boxes is a line made up of several stations in which semi-finished products are processed to obtain covered boxes. More specifically, the line 1 is configured o process a plurality of covering blanks and a plurality of box blanks in order to obtain respective covered cardboard boxes.

[0116] In one embodiment, the line 1 comprises a base 1A.

[0117] In one embodiment, the line 1 comprises a conveyor unit 2.

[0118] In one embodiment, the conveyor unit 2 is connected to the base 1A.

[0119] In one embodiment, the conveyor unit 2 is configured to convey the covering blanks along a movement path.

[0120] In one embodiment, the conveyor unit 2 comprises a belt 2A.

[0121] In one embodiment, the conveyor unit 2 comprises a conveyor actuator 2B.

[0122] In one embodiment, the belt 2A of the conveyor unit 2 is movable to transport a plurality of covering blanks from a loading position C to an unloading position S.

[0123] The movement path is characterized by a movement orientation and a direction of movement V. More specifically the direction of movement V is oriented from the loading position C to the unloading position S.

[0124] In one embodiment, the conveyor actuator 2B is connected to the belt 2A.

[0125] In one embodiment, the conveyor actuator 2B is configured to drive the belt 2A. In one embodiment, the conveyor actuator 2B is configured to drive the belt 2A intermittently, in an alternating sequence of movements and stops. In one embodiment, the line 1 comprises a conveyor section 10A. In one embodiment, the conveyor section 10A is configured to transport the box blanks to a coupling position A on the belt 2A, interposed between the loading position C and the unloading position S. in one embodiment, the line 1 comprises an insertion actuator 10B. In one embodiment, the insertion actuator 10B is configured to drive the conveyor section 10A. In one embodiment, the feed actuator 10B coincides with the conveyor actuator 2B. In this embodiment, the drive motion provided by the conveyor actuator 2B is transmitted to the conveyor section 10A through suitable drive transmission means.

[0126] In one embodiment, the line 1 comprises a feed unit 3.

[0127] In one embodiment, the feed unit 3 is connected to the base 1A. In one embodiment, the feed unit 3 comprises a load-bearing structure 3A.

[0128] In one embodiment, the load-bearing structure 3A of the feed unit 3 is integral with the base 1A.

[0129] The feed unit 3 is configured to pick up the covering blanks from a reservoir. In one embodiment, the reservoir is a shelf 4 which is connected to the feed unit 3 and on which the plurality of covering blanks is stacked.

[0130] In one embodiment, the shelf 4 is configured to move translationally along a stacking direction, along which the covering blanks are stacked. This allows the shelf 4 to adapt to the number of covering blanks present on the shelf 4 itself, which moves progressively closer to the feed unit 3 until all the covering blanks are finished.

[0131] In one embodiment, the feed unit 3 is configured to feed the covering blanks individually to the conveyor unit 2. In one embodiment, the feed unit 3 is configured to feed the covering blanks individually to the conveyor unit 2 at the loading position C, in a sequence of feed instants.

[0132] In one embodiment, the conveyor unit 2 comprises a pickup device 5. In one embodiment, the pickup device 5 is configured to pick up the covering blanks from the shelf 4. In one embodiment, the pickup device 5 comprises a suction cup 5A′. In one embodiment, the pickup device may comprise more than one suction cup 5A′. The suction cup 5A′ is configured to pick up a single covering blank from the plurality of covering blanks disposed on the shelf 4.

[0133] In one embodiment, the pickup device 5 comprises a translating head 5A. In one embodiment, the pickup device 5 comprises a slide 5B.

[0134] In one embodiment, the translating head 5A is configured to move translationally along the slide 5B to pick up the covering blanks in a zone which is distal from the loading position C and to move a single covering blank close to a zone which is proximal to the loading position C.

[0135] In one embodiment, the feed unit 3 comprises a plurality of feed rollers 6. In one embodiment, the plurality of feed rollers 6 is configured to receive a single covering blank picked up from the shelf 4 and to feed it to the loading position C of the belt 2A.

[0136] In one embodiment, at least two rollers of the plurality of feed rollers 6 rotate in opposite directions in such a way as to bring the covering blank up to the loading position C on the belt 2A.

[0137] In one embodiment, the translating head 5A is configured to release the covering blank at the plurality of feed rollers 6.

[0138] The plurality of feed rollers 6 is configured to retain the covering blank until reaching the feed instant of the plurality of feed instants.

[0139] In one embodiment, the feed unit 3 comprises a feed actuator 3B. In one embodiment, the feed unit 3B is connected to the translating head 5A. In one embodiment, the feed actuator 3B is connected to the plurality of feed rollers 6.

[0140] In one embodiment, the feed actuator 3B is connected to the feed unit 3 to pick up the covering blanks from a reservoir.

[0141] In one embodiment, the feed actuator 3B is connected to the translating head 5A of the pickup device 5 to pick up the covering blanks from the shelf 4.

[0142] In one embodiment, the feed actuator 3B is connected to the feed unit 3 to feed one covering blank at a time to the loading position C on the belt 2A.

[0143] In one embodiment, the feed actuator 3B is connected to the plurality of feed rollers 6 to feed one covering blank at a time to the loading position C on the belt 2A.

[0144] In one embodiment, the feed actuator 3B coincides with the conveyor actuator 2B. In this embodiment, the conveyor actuator 2B and the feed unit 3 are connected. In one embodiment, there is a variation unit 3B′ interposed between the conveyor actuator 2B and the feed unit 3.

[0145] The variation unit 3B′ is configured to vary the drive motion from the conveyor actuator 2B and to transmit it to the feed unit 3.

[0146] In one embodiment, the variation unit 3B′ is configured to vary a feed instant relative to an activation instant of the conveyor actuator 2B. In this embodiment, the variation unit 3B′ is configured to transmit torque or drive power to the feed unit 3 with a phase displacement relative to the instant at which the torque or drive power is supplied to the conveyor actuator 2B.

[0147] In one embodiment, the variation unit 3B′ is configured to vary the intensity of the drive power.

[0148] In one embodiment, the variation unit 3B′ comprises a friction clutch. The friction clutch comprises a first part which is integral with the conveyor actuator 2B and a second part which is integral with the feed unit 3. The friction clutch is configured to guarantee a phase displacement s between the instant at which the first part of the friction clutch starts moving and the instant at which the second part of the friction clutch engages the first part of the friction clutch.

[0149] This embodiment is mentioned purely by way of example. An expert in the trade would be capable of designing different types of variations units configured to phase-displace the transmission instant relative to the activation instant of the conveyor actuator 2B. By way of non-limiting example, systems comprising cam profiles might also be used.

[0150] In one embodiment, the line 1 comprises an erecting machine 7. The erecting machine 7 is configured to receive the cardboard box blanks and to fold them to form corresponding boxes. The erecting machine 7 is connected to the base 1A of the line 1.

[0151] In one embodiment, the erecting machine 7 is located along the conveyor section 10A. In one embodiment, the conveyor section 10A is configured to transport box blanks to the erecting machine 7. In one embodiment, the conveyor section 10A is configured to pick up the box blanks which have been folded in the erecting machine 7 and to transport them to the coupling position A on the belt 2A of the conveyor unit 2.

[0152] In one embodiment, the line 1 comprises a positioner 8.

[0153] In one embodiment, the positioner 8 is configured to receive the boxes from the erecting machine 7. In one embodiment, the positioner 8 is configured to position the boxes individually in alignment on corresponding covering blanks disposed on the belt 2A of the conveyor unit 2, at a coupling position A interposed between the loading position C and the unloading position S.

[0154] In one embodiment, the positioner 8 is rigidly connected to the base 1A of the line 1. The rigid connection reduces the vibrations of the positioner 8 and thus allows greater positioning precision.

[0155] In one embodiment, the positioner 8 is configured to receive the covering blanks by from the belt 2A of the conveyor unit 2. In one embodiment, the positioner 8 is configured to receive the boxes from the conveyor section 10A after they have been folded in the erecting machine 7.

[0156] In one embodiment, the line 1 comprises a gluer 10. In one embodiment, the gluer 10 is configured to spread glue on one face of the covering blanks which will come into contact with a corresponding surface of the boxes to be covered.

[0157] In one embodiment, the gluer 10 is connected to the feed unit 3. In one embodiment, the gluer 10 is located between the loading position C on the belt 2A and the feed unit 3.

[0158] In one embodiment, the gluer 10 comprises an idle arm 10′. In one embodiment, the glue to be spread on the face of the covering blanks which will come into contact with a corresponding surface of the boxes to be covered is present on a free end of the idle arm 10′. In one embodiment, the idle arm 10′ is movable idly in such a way as to remain in contact with the face of the covering blank without damaging it. In one embodiment, the idle arm 10′ comprises a spring configured to keep the idle arm 10′ in contact with the face of the covering blank.

[0159] In one embodiment, the line 1 comprises a covering machine 9. In one embodiment, the covering machine 9 is configured to receive the boxes coupled to the respective covering blanks from the conveyor unit 2 at the unloading position S. In one embodiment, the covering machine 9 is configured to fold the covering blank into contact with the respective box in such a way as to cover it.

[0160] In one embodiment, the covering machine 9 is rigidly connected to the base 1A of the line 1. The rigid connection reduces the vibrations of the covering machine 9 and thus allows greater covering precision.

[0161] In one embodiment, the line 1 comprises a control unit 11.

[0162] In one embodiment, the line 1 comprises a user interface. The user interface is connected to the control unit 11.

[0163] In one embodiment, the user interface is local. In this embodiment, the user interface may be a display 11A which is physically connected to the machine.

[0164] In one embodiment, the user interface is remote. In this embodiment, the user interface may be a smartphone, a tablet or a portable computer or any device capable of being remotely connected to the control unit 11.

[0165] In one embodiment, the control unit 11 is connected to the feed unit 3. In one embodiment, the control unit 11 is connected to the feed unit 3 to adjustably set a phase displacement s of the feed instants relative to the sequence of stops of the belt 2A.

[0166] In one embodiment, the control unit 11 is connected to the conveyor unit 2. In one embodiment, the control unit 11 is connected to the positioner 8. In one embodiment, the control unit 11 is connected to the covering machine 9. In one embodiment, the control unit 11 is connected to the erecting machine 7. In one embodiment, where the line 1 comprises the feed actuator 3B, the control unit 11 is connected to the feed actuator 3B.

[0167] In one embodiment, where the machine comprises the variation unit 3B′, the control unit 11 is connected to the variation unit 3B′.

[0168] In one embodiment, the control unit 11 is programmed to activate the feed actuator 3B and the conveyor actuator 2B in a synchronous and phase-displaced manner according to the phase displacement s of the feed instants relative to the corresponding stops of the belt 2A.

[0169] In this embodiment, the control unit 11 is configured to send a convey signal 12A and a feed signal 12B.

[0170] The convey signal 12A is sent to the conveyor actuator 2B. The feed signal 12B is sent to the feed actuator 3B. The control unit 11 is programmed to send the convey signal 12A and the feed signal 12B in a synchronous and phase-displaced manner according to the phase displacement s of the feed instants relative to the corresponding stops of the belt 2A. The convey signal 12A and the feed signal 12B are received by the conveyor actuator 2B and by the feed actuator 3B, respectively, which in turn drive the conveyor unit 2 and the feed unit 3, respectively.

[0171] In one embodiment, the control unit 11 is programmed to activate the feed actuator 3B in the sequence of feed instants, which are temporally located in respective time intervals in which the belt 2A is in motion.

[0172] In one embodiment, the control unit 11 is programmed to send the feed signal 12B in the sequence of feed instants, which are temporally located in respective time intervals in which the convey signal 12A has already been received by the conveyor actuator 2B.

[0173] In one embodiment, the control unit 11 is connected to the conveyor actuator 2B to vary the sequence of movements and stops of the belt 2A.

[0174] In one embodiment, the control unit 11 is configured to receive order data 100. In one embodiment, the order data 100 include format data 100A representing a format of the covering blanks.

[0175] In one embodiment, the order data 100 include productivity data 100B representing the quantity to be produced for a given format.

[0176] In one embodiment, the order data 100 refer to a plurality of orders to be processed in the machine. More specifically, in this embodiment, the order data 100 include an order sequence. In one embodiment, the order sequence comprises, for each order in the sequence, the format data 100A and the productivity data 100B.

[0177] In one embodiment, the control unit 11 is configured to process the order data 100. In one embodiment, the control unit 11 is configured to process the format data 100A and to set the sequence of movements and stops of the belt 2A.

[0178] In one embodiment, the control unit 11 is configured to process the format data 100A and to set working data 101 representing the sequence of movements and stops of the belt 2A as a function of the format data 100A.

[0179] In one embodiment, the control unit 11 is configured to process the order data 100 and to set the working data 101.

[0180] In one embodiment, the working data 101 include the phase displacement s of the feed instants relative to the sequence of stops of the belt 2A.

[0181] In one embodiment, the working data 101 include one or more of the following parameters:

[0182] a working spacing p, defined by a distance between two consecutive covering blanks disposed on the belt 2A, measured in a direction of maximum extension of the belt 2A;

[0183] a speed of the belt 2A;

[0184] a duration of the stops of the belt 2A;

[0185] a stop/move repetition period T;

[0186] a number of pieces to be produced for each format;

[0187] tool force, speed and trajectory of the erecting machine 7, covering machine 9 and positioner 8;

[0188] a speed of the conveyor section 10A.

[0189] In one embodiment, the control unit 11 is configured to process an order time schedule 102 as a function of the productivity data 1006.

[0190] The order time schedule 102 allows the control unit 11 to perform a changeover automatically and without significant stops. The order time schedule 102 allows the control unit 11 to adapt the working data 101 automatically and without significant stops.

[0191] More specifically, the control unit 11 is configured to vary the sequence of movements and stops of the belt 2A as a function of the order time schedule 102.

[0192] In one embodiment, the belt 2A of the conveyor unit 2 comprises a suction unit. The suction unit is configured to apply a suction force perpendicularly to a plane containing the belt 2A and directed from the belt 2A to a supporting surface on which the base 1A of the line 1 is rested or fixed.

[0193] In one embodiment, the belt 2A comprises a first suction zone 2A′. The first suction zone 2A′ is adjacent to the feed unit 3. The first suction zone 2A′ is configured to apply a first suction force P1.

[0194] In one embodiment, the belt 2A comprises a second suction zone 2A″. In one embodiment, the second suction zone 2A″ is spaced from the feed unit 3. The second suction zone 2A″ is configured to apply a second suction force P2.

[0195] In one embodiment, the second suction force P2 is smaller than the first suction force P1. This allows the belt 2A to keep the covering blank more adherent to the belt 2A during the feed step F2, where the probability of its coming away is higher because feeding occurs with the belt 2A already in motion.

[0196] According to one aspect of this disclosure, this invention provides a method for making covered cardboard boxes.

[0197] In one embodiment, the method comprises a step F1 of intermittently conveying a plurality of covering blanks from a loading position C to an unloading position S.

[0198] In one embodiment, the step F1 of intermittently conveying is performed by means of a conveyor unit 2 including a belt 2A which is driven intermittently by a conveyor actuator 2B in an alternating sequence of movements and stops.

[0199] Hereinafter, Ts is used to denote a stop time, that is, the length of time in which the belt 2A is not driven, Ta a movement time, that is, the length of time in which the belt 2A is driven and T the period, that is the time from one starting of the belt 2A to the next starting, equal to the sum of the stop time Ts plus the movement time Ta. The speed of the belt 2A when in motion is denoted by the letter v.

[0200] During the step of conveying, the conveyor actuator 2B drives the belt 2A. The belt 2A carries the covering blanks on its surface and transports them along a movement path in a direction of movement V, oriented from the loading position C to the unloading position S.

[0201] In one embodiment, the belt 2A moves intermittently.

[0202] In another embodiment, the belt 2A can move continuously. In one embodiment, the belt 2A, when in motion, moves at a constant speed v. In another embodiment, the belt 2A, when in motion, moves at variable speed. In this embodiment, the variable speed might fulfil the need for a buffer station.

[0203] In one embodiment, the step F1 of conveying is a step of conveying the covering blank coupled to the previously erected box up to the unloading position S.

[0204] In one embodiment, the step F1 of conveying is a step of conveying a plurality of box blanks along a conveyor section 10A, outside of and merging into the belt 2A in a coupling position A, interposed between the loading position C and the unloading position S on the belt 2A.

[0205] In one embodiment, the step F1 of conveying is a step of conveying a formed box, obtained by folding a box blank of the plurality of box blanks, along the conveyor section 10A up to the coupling position A on the belt 2A.

[0206] In one embodiment, the method comprises a step of picking up covering blanks individually from a reservoir by means of a feed unit 3. In one embodiment, the method comprises a step F2 of feeding the covering blanks to the loading position C of the belt 2A by means of the feed unit 3, in a sequence of feed instants.

[0207] In one embodiment, the step F2 of feeding the covering blanks to the loading position C of the belt 2A is performed with the belt 2A of the conveyor unit 2 in motion.

[0208] In one embodiment, in which the feed unit 3 comprises a feed actuator 3B which is separate from the conveyor actuator 2B, the feed actuator 3B drives the feed unit 3 to feed the covering blanks.

[0209] Hereinafter, the term “feed instant la” will be used to denote an instant at which the feed unit 3 starts feeding the covering blank to the conveyor unit 2, the term “starting instant t.sub.0”, an instant at which the conveyor actuator 2B starts driving the belt 2A and the term “stop instant ts”, an instant at which the conveyor actuator 2B stops driving the belt 2A. Hereinafter, the term “spacing p” will be used to denote the distance along the belt 2A between two consecutive covering blanks located on the belt 2A. The reference Tf in the drawings denotes a feed time, meaning by this the time that elapses between the feed instant and an instant at which the covering blank is effectively placed in the loading position C of the belt 2A.

[0210] In one embodiment, during the step of picking up, a pickup device 5 picks up a single covering blank from a shelf 4 on which the plurality of covering blanks is stacked.

[0211] In one embodiment, in which the pickup device 5 comprises a translating head 5A and a slide 5B, the translating head 5A engages the single covering blank to be fed. In one embodiment, the translating head 5A moves translationally along the slide 5B to carry the single covering blank from a position which is distal from the loading position C on the belt 2A to a position which is proximal to the loading position C on the belt 2A.

[0212] In one embodiment, in which the translating head 5A comprises a suction cup 5A′, the latter engages the single covering blank to be fed.

[0213] In one embodiment, in which the feed unit 3 comprises a plurality of feed rollers 6, the pickup device 5 releases the single covering blank in proximity to the feed rollers so that the latter can receive it.

[0214] In one embodiment, at least two rollers of the plurality of feed rollers 6 rotate in opposite directions. In one embodiment, during the step F2 of feeding, the single covering blank to be fed is disposed between the at least two feed rollers rotating in opposite directions.

[0215] In one embodiment, the plurality of feed rollers 6 rotate and in doing so carry the single covering blank along with them in such a way as to feed it to the loading position C of the belt 2A.

[0216] In one embodiment, in which the feed actuator 3B is separate from the conveyor actuator 2B, the feed actuator 3B drives the plurality of feed rollers 6 in order to feed the covering blanks.

[0217] In one embodiment, in which the feed actuator 3B is separate from the conveyor actuator 2B, the feed actuator 3B drives the pickup device 5 to pick up the covering blanks.

[0218] In one embodiment, the method comprises a secondary step F2′ of feeding, in which a box blank of the plurality of box blanks is picked up individually from secondary reservoir and fed individually to a conveyor section 10A.

[0219] In one embodiment, the method comprises a step of receiving box blanks in an erecting machine 7. In one embodiment, the method comprises a step F3 of folding the box blanks to form corresponding boxes.

[0220] In one embodiment, the method comprises a step F4 of positioning each box in alignment on a corresponding covering blank disposed on the belt 2A. In one embodiment, the step F4 of positioning is carried out at a coupling position A, interposed between the loading position C and the unloading position S.

[0221] In one embodiment, the method comprises a step of spreading glue on one face of the covering blanks which will come into contact with a corresponding surface of the boxes to be covered, which will hereinafter be referred to as inside face of the covering blank.

[0222] In one embodiment, during the step of spreading glue, the single covering blank to be fed is made to pass through a gluer 10 before reaching the loading position C on the belt 2A. In one embodiment, the gluer 10 spreads glue on the inside face of the covering blank while the latter is in motion.

[0223] In one embodiment, in which the gluer 10 comprises an idle arm 10′, a free end of the idle arm 10′ where the glue is, remains in contact with the inside face of the covering blank as the latter moves towards the loading position C of the belt 2A.

[0224] In one embodiment, the method comprises a step of feeding the boxes coupled to the respective covering blanks to a covering machine 9.

[0225] In one embodiment, the covering machine 9 folds the covering blank into contact with the respective box in such a way as to cover the box.

[0226] In one embodiment, the method comprises a step F5 of covering a box with its respective covering blank.

[0227] In one embodiment, the method comprises a step F6 of adjustably setting a phase displacement s of the feed instants relative to the sequence of stops of the belt 2A. This step F6 of adjustably setting is performed by a control unit 11.

[0228] In one embodiment, the method comprises a step F61 of entering format data. During this step, a machine operator using a local or remote interface can enter format data representing a format of the covering blanks.

[0229] In one embodiment, the method comprises a step F62 of receiving format data. During this step, the control unit 11 receives the format data 100A from the user interface for processing.

[0230] In one embodiment, the method comprises a step F63 of processing format data.

[0231] During the step F63 of processing format data, the control unit 11 processes the format data 100A to determine working data 101 which include the phase displacement s of the feed instants relative to the sequence of stops of the belt 2A.

[0232] During the step F63 of processing format data, the control unit 11 takes the following quantities into account:

[0233] Distance of the feed unit from the positioner 8, hereinafter denoted D1

[0234] Distance of the positioner 8 from the covering machine 9, hereinafter denoted D2

[0235] Speed v of the belt 2A

[0236] Spacing p limit (p.sub.lim), being the minimum distance along the belt 2A between two consecutive covering blanks disposed on the belt 2A, determined as a function of the size of the covering blank.

[0237] In one embodiment, the step F63 of processing format data comprises a first step of determining the spacing p. The spacing p is a function of the distance D2 and of the limit spacing p.sub.lim.

[0238] More specifically, in one embodiment, the spacing p can be determined with the following formula:

[00001]$p=D2\text{/}.Math.\frac{D2}{p_{\lim }}.Math.$

[0239] Where the spacing p is determined by the distance D2 divided by the whole number part of the result of division of D2 and the spacing p.sub.lim.

[0240] In one embodiment, the spacing p thus determined is the minimum spacing p obtainable as a function of the limit spacing although there might be other constraints which are not mentioned in this specification.

[0241] It is understood that it is not an aim of this specification to describe how the spacing p is determined and the above is set out purely by way of non-limiting example.

[0242] In one embodiment, the step F63 of processing format data comprises a step of determining a phase displacement distance f.

[0243] More specifically, in one embodiment, the phase displacement distance f can be determined with the following formula:

[00002]$f=\left(\frac{D1}{p}\text{/}.Math.\frac{D1}{p}.Math.\right)*p$

[0244] Knowing the speed of the belt 2A automatically allows determining the phase displacement s of the feed instants relative to the sequence of stops of the belt 2A.

[00003]$s=\frac{f}{v}$

[0245] In this case, too, it is stressed that the analytical relations set out above are not intended to exhaustively describe the mathematical methods used to determine the phase displacement distance f and the phase displacement s of the feed instants relative to the stops of the belt 2A. What is set out above therefore is of non-limiting, exemplary nature and relates to one of the possible embodiments of the step of processing format data 100A.

[0246] In one embodiment, the step F6 of adjustably setting comprises sending a phase displacement signal to the conveyor unit 2 and to the feed unit 3.

[0247] In one embodiment, during the step of adjustably setting F6 the control unit 11 sends a convey signal 12A to the conveyor unit 2.

[0248] In one embodiment, during the step F6 of adjustably setting the control unit 11 sends a feed signal 12B to the feed unit 3.

[0249] In one embodiment, during the step F6 of adjustably setting the control unit 11 sends a convey signal 12A to the conveyor actuator 2B.

[0250] In one embodiment, in which the feed unit 3 comprises a feed actuator 3B which is separate from the conveyor actuator 2B, during the step F6 of adjustably setting the control unit 11 sends a feed signal 12B to the feed actuator 3B.

[0251] More specifically, the control unit 11 may advance or delay the feed instant as a function of the value of the phase displacement s. Delayed feeding is when the control unit 11 delays the feed instant and, vice versa, advanced feeding is when the control unit 11 advances the feed instant.

[0252] The advanced feed and delayed feed configurations are described below.

[0253] Advanced feed and delayed feed are illustrated in FIGS. 6A and 6B, respectively. For a clearer understanding of these drawings, it should be noted that to denotes a start instant and is denotes a stop instant. The other symbols used in the drawings were explained previously.

[0254] The alternating sequence of movements and stops defines a sequence of start instants and a sequence of stop instants.

[0255] In one embodiment, in which feeding is advanced, the control unit 11 sends the convey signal 12A to the conveyor actuator 2B at a start instant to of the sequence of start instants. The convey signal 12A is maintained for the entire movement time Ta of the belt 2A.

[0256] In one embodiment, the control unit 11 sends the feed signal 12B at the feed instant, which is advanced by a quantity equal to the phase displacement s relative to a stop instant is of the belt 2A of the sequence of stop instants.

[0257] In this embodiment, when the belt 2A is started again, the covering blank is already on the belt 2A and, more specifically, is advanced by a distance equal to the phase displacement distance f. This allows the covering blank to be located at the coupling position A on the belt 2A, where it would not have arrived with the spacing p if feed were not advanced.

[0258] In one embodiment, in which feeding is delayed, the control unit 11 sends the convey signal 12A to the conveyor actuator 2B at a start instant to of the sequence of start instants. The convey signal 12A is maintained for the entire movement time Ta of the belt 2A.

[0259] In one embodiment, the control unit 11 sends the feed signal 12B at the feed instant, which is delayed by the phase displacements relative to the feed instant of the belt 2A.

[0260] In this embodiment, when the belt 2A is started again to convey the next blank, the preceding covering blank is behind by a distance equal to the phase displacement distance f. This allows the covering blank to be located at the coupling position A on the belt 2A, which it would otherwise pass by the spacing p if feed were not delayed.

[0261] In both cases, if feed were not delayed or advanced and if, instead, the spacing p were adjusted in such a way as to be exactly at the coupling position A, there would be misalignment at the covering machine 9. The only way to obtain correct placement both at the coupling position A on the positioner 8 and on the covering machine 9 is to vary the mutual distances between feed unit 3, positioner 8 and covering machine 9. The feed time delay, because it occurs with the belt 2A in motion, has the same technical effect as varying the distance between the feed unit 3 and the positioner 8 but has the big advantage of not requiring heavy weights to be moved.

[0262] In one embodiment, the control unit 11 activates the feed actuator 3B and the conveyor actuator 2B synchronously.

[0263] In one embodiment, the control unit 11 activates the feed actuator 3B and the conveyor actuator 2B in a phase-displaced manner as a function of the phase displacement s of the feed instants relative to the corresponding stops of the belt 2A.

[0264] In one embodiment, the control unit 11 activates the feed actuator 3B and the conveyor actuator 2B in a synchronous and phase-displaced manner as a function of the phase displacement s of the feed instants relative to the corresponding stops of the belt 2A.

[0265] In one embodiment, the control unit 11 sets the phase displacement s by sending the convey signal 12A and the feed signal 12B in a synchronous and phase-displaced manner to the conveyor actuator 2B and the feed actuator 3B, respectively.

[0266] In one embodiment, the control unit 11 sets the phase displacement s by sending the phase displacement signal to the feed unit 3.

[0267] In one embodiment, in which the feed unit 3 comprises a variation unit 3B′, the control unit 11 sets the phase displacement s by sending to the variation unit 3B′ the phase displacement signal as a function of which the variation unit 3B′ delays or advances the drive motion from the conveyor actuator 2B.

[0268] In one embodiment, the method comprises a step F71 of entering order data. During the step F71 of entering order data, a machine operator enters the order data 100. In one embodiment, the order data 100 include the format data 100A. In one embodiment, the order data 100 include the format data 100A of two or more orders to be processed in sequence in the line 1. In one embodiment, the order data 100 include productivity data 100B. In one embodiment, the order data 100 include the productivity data 100B of two or more orders to be processed in sequence in the line 1.

[0269] In one embodiment, the order data 100 include a time sequence of the orders to be processed and tool specifications of the erecting machine 7, the positioner 8 or of the covering machine 9. In one embodiment, the order data 100 include all the information necessary for the line 1 to complete a working cycle on a batch and to complete the time sequence of two or more batches.

[0270] In one embodiment, the method comprises a step F72 of processing order data. During the step F72 of processing order data, the control unit 11 processes the order data 100 and sets working data 101.

[0271] In one embodiment, the control unit 11 varies the sequence of movements and stops of the belt 2A as a function of the order data 100.

[0272] In one embodiment, the control unit 11 varies the sequence of movements and stops of the belt 2A as a function of the format data 100A.

[0273] In one embodiment, the method comprises a step F73 of setting working data.

[0274] In one embodiment, during the step F73 of setting working data, the control unit 11 receives the format data 100A, representing a format of the covering blanks, and sets the sequence of movements and stops of the belt 2A as a function of the format data 100A.

[0275] In one embodiment, during the step of setting working data 101, the control unit 11 receives the order data 100 and sets the working data 101.

[0276] In one embodiment, the method comprises a step F8 of saving an order time schedule. During this step, the control unit 11, having processed the order data 100, creates an order time schedule 102, representing a time sequence of batches to be processed.

[0277] In one embodiment, the method comprises a step of automatic changeover. In one embodiment, during the step of automatic changeover, the control unit 11 is configured to automatically vary the alternating sequence of movements and stops as a function of the order time schedule 102.

[0278] In one embodiment, during the step of automatic changeover, the control unit 11 is configured to automatically vary the phase displacement s of the feed instants relative to the sequence of stops of the belt 2A, as a function of the order time schedule 102.

[0279] In one embodiment, during the step of automatic changeover, the control unit 11 is configured to automatically vary the working data 101, as a function of the order time schedule 102.

[0280] In one embodiment, the method comprises a step of applying suction.

[0281] In one embodiment, the step of applying suction comprises a first step of applying suction. During the first step of applying suction, a first suction zone 2A′ of the belt 2A, adjacent to the feed unit 3, applies a first suction force P1 on the covering blanks. In one embodiment, the step of applying suction comprises a second step of applying suction. During the second step of applying suction, a second suction zone 2A″ of the belt 2A, spaced from the feed unit 3, applies a second suction force P2 on the covering blanks.

[0282] In one embodiment, the second suction force P2 is smaller than the first suction force P1. This improves adherence to the belt 2A at the loading position C where dynamic feeding of the covering blanks might negatively affect the quality of the finished product.