Blank supply unit for a packaging machine with position reference elements - Patent Application 20070122637

Abstract

A feeding unit (13) for feeding blanks (1) in a packaging machine comprises: a frame (14); a hopper (15) supported by the frame (14), designed to hold a stack of blanks (1), having an unloading opening (16) for unloading blanks (1) one at a time from the stack; and a conveyor (17) supported by the frame (14) for moving the blanks (1) along a movement path (P) that terminates in the hopper (15). To accommodate blanks (1) having different mold types, the feeding unit (13) can be adjusted by a mold type change operating means that changes the feeding unit (13) from a first configuration suitable for containing a first mold type of blanks (1) to a second configuration suitable for containing a second mold type of blanks (1) different from the first mold type. The hopper (15) has a reference element (23) which is placed in contact with the stack of blanks (1) in use and which establishes a positional reference for the blanks (1) in the stack of blanks (1), and which is in the same position relative to the frame (14) regardless of the type of blank (1) and therefore is not moved relative to the frame (14) for type change operations.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This patent application claims priority to Italian Patent Application No. 102020000016717, filed September 7, 2020, the entire disclosure of which is incorporated herein by reference. The present invention relates to a blank supply unit for a packaging machine. [Background technology]

[0002] Packaging machines generally fold blanks around the product to be packaged or fold blanks to obtain empty packaging designed to contain the product to be packaged inside. Consequently, packaging machines generally comprise a blank supply unit that accommodates a stack of blanks in a hopper and makes it possible to remove single blanks one after the other from the bottom of the stack (located in the area of ​​the removal opening of the hopper) in order to orient the single blanks towards the fold line.

[0003] In the region of the unloading opening, the hopper has retaining elements that serve to support the blanks placed inside the hopper and prevent them from escaping in an uncontrolled and disorderly manner. To remove a blank from the unloading opening of the hopper, (at least) a suction holding head engages the blank and pulls it in a movement that allows the edges of the blank to slide out of the holding elements; during the unloading operation, the blank is generally slightly deformed to facilitate the removal of the edges of the blank from the holding elements.

[0004] Modern packaging machines are increasingly subject to die format changes, i.e., a series of technical interventions aimed at adjusting the production of packaging material to a different die format (size). In other words, to shift from producing packaging material of a given size (die format) to producing packaging material of a different size (die format), the operator must manipulate various parts of the packaging machine to adapt them to the new size (die format). Changing the size (die format) of packaging material obviously requires the use of blanks of a different size (die format), and therefore the hoppers of the feeding units must be adjusted to accommodate and dispense blanks of a different size (die format). Summary of the Invention [Problem to be solved by the invention]

[0005] The process of changing the type of blank hopper is particularly time-consuming and complicated, since it requires repeated attempts to correctly adjust the position of the retaining elements arranged in the area of ​​the unloading opening. In fact, the position of the retaining elements must be the result of a complex compromise between the need to properly hold the stack of blanks in the hopper (thus avoiding the accidental removal of one or more adjacent blanks when unloading a blank) and the need to avoid damaging (denting or scratching) the edges of the blanks when unloading them. That is, the retaining elements must protrude sufficiently into the unloading opening to properly hold the stack of blanks in the hopper, but not too far into the unloading opening to avoid damaging the edges of the blanks during the unloading operation. [Means for solving the problem]

[0006] The object of the present invention is to provide a blank supply unit for a packaging machine, which allows die type changes to be carried out very quickly, while at the same time ensuring ideal retention of the blanks (i.e. ensuring that no damage is caused to the edges of the blanks during the removal operation). According to the present invention, there is provided a blank supply unit for a packaging machine as claimed in the accompanying claims. The appended claims describe embodiments of the invention and form an integral part of the description. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a plan view of a blank used to manufacture a packaging designed to contain a group of coffee capsules. [Figure 2] FIG. 2 is a plan view of three different blanks stacked on top of each other. [Figure 3] FIG. 3 is a rear perspective view of a blank supply unit for a packaging machine, containing a stack of blanks. [Figure 4] FIG. 4 is a front perspective view of the supply unit of FIG. 3, including a stack of blanks. [Figure 5] FIG. 5 is a rear perspective view of the hopper of the feed unit of FIG. 3 without the stack of blanks. [Figure 6] FIG. 6 is a rear perspective view of a portion of the hopper of FIG. [Figure 7] FIG. 7 is a front perspective view of a portion of the hopper of FIG. [Figure 8] FIG. 8 is a front view of a portion of the hopper of FIG. [Figure 9] FIG. 9 is a front perspective view of the detail of FIG. [Figure 10] FIG. 10 is a rear perspective view of the supply unit of FIG. 3 without a stack of blanks and with the support in the change position. [Figure 11] FIG. 11 is another rear perspective view of the supply unit of FIG. 3, without the stack of blanks. DETAILED DESCRIPTION OF THE INVENTION

[0008] In Figure 1, the number 1 indicates as a whole a blank used to manufacture a pack designed to contain a group of coffee capsules.

[0009] The blank 1 has two (pre-weakened) longitudinal fold lines 2 and, between the two longitudinal fold lines 2, a number of (pre-weakened) transverse fold lines 3 which define a panel 4 constituting the top wall of the package, a panel 5 constituting the rear wall of the package, a panel 6 constituting the bottom wall of the package, and a panel 7 constituting the front wall of the package. On either side of panel 5 there are two panels 8 which form the side walls of the package and are connected to panel 5 by the two longitudinal fold lines 2. Panels 4 and 5 have a coffee capsule dispensing opening which is normally closed by a hinged lid 9.

[0010] The blank 1 comprises two vanes 10 connected to the longitudinal fold lines 2 and two vanes 11 opposite the vanes 10 and connected to the other longitudinal fold line 2; in particular, the two vanes 10 and 11 are arranged at opposite ends of the panel 6 and connected to the panel 6 by two longitudinal fold lines 2, and the other two vanes 10 and 11 are arranged at opposite ends of the panel 7 and connected to the panel 7 by two longitudinal fold lines 2. The vanes 10 delimit triangular free spaces with vertices 12 in the area of ​​the longitudinal fold lines 2.

[0011] According to FIG. 2, there are blanks 1 (all with the same conformation, i.e., the same arrangement of panels and wings) with different mould types (i.e., different sizes) from which corresponding packaging materials with smaller or larger dimensions (i.e., intended to accommodate different numbers of capsules and / or capsules with different sizes) are produced.

[0012] All blanks 1 having different mold formats (different sizes) can be stacked on top of each other by using the corresponding vertices 12 as a position reference, i.e., by always keeping the corresponding vertices 12 in the same position (as shown in FIG. 2). In other words, all blanks 1 having different mold formats (different sizes) can be stacked on top of each other by aligning the corresponding vertices 12 with each other, so that the vertices 12 are in the same position (as shown in FIG. 2).

[0013] In FIG. 3, the reference numeral 1 generally denotes a blank for feeding the blanks 1 in a packaging machine designed to package coffee capsules. of Supply Unit 13 In particular, the packaging machine comprises a supply unit 13 which takes a single blank 1 from a stack of blanks 1, a packaging unit which receives the single blank 1 from the supply unit 13 and folds the blank 1 to form an empty and open package (i.e. the top wall is raised relative to the rest of the package), a filling unit in which a robotic arm inserts a single coffee capsule into the open package, and a closing unit in which the filled package is closed (i.e. the top wall is resting and glued relative to the rest of the package).

[0014] According to Fig. 3, the supply unit 13 comprises a frame 14 resting on its legs on the ground and a hopper 15 carried by the frame 14, designed to contain a stack of blanks 1 and having an unloading opening 16 (visible for example in Fig. 5) by means of which one blank 1 can be removed from the stack of blanks 1 at a time. Furthermore, the supply unit 13 comprises a conveyor 17 supported by the frame 14 and moving the blanks 1 along a straight and horizontal movement path P that ends in the hopper 15, the movement path P also being inclined relative to the horizontal with a (small or large) inclination towards the hopper 15 so that gravity tends to move the blanks 1 towards the hopper 15. Finally, the supply unit 13 comprises an unloading device (not shown) which is arranged in the region of the unloading opening 16 of the hopper 15 and which, in use, engages with the unloading opening 16 in order to remove single blanks 1 from the stack one after another and feed the blanks 1 towards the packaging unit.

[0015] The unloading device (not shown) comprises a rotating drum that rotates about its central axis, and at least one suction holding head supported by the drum and moving cyclically along a closed path through holding stations, where the holding head engages with an unloading opening 16 of the hopper 15 to unload the blank 1, and then through a subsequent release station where the holding head supplies the blank 1 to the filling unit. Because the dimensions of the unloading opening 16 are smaller than the dimensions of the blank 1 (as will be described below), the blank 1 must be elastically deformed to be unloaded from the unloading opening 16 of the hopper 15 (as would be required to hold the blank 1 inside the hopper 15 in the absence of the unloading device).

[0016] The hopper 15 has a flattened storage wall 18 having a rectangular shape (positioned approximately perpendicular to the movement path P) with a through hole 19 (better seen in Figures 5, 6, and 7) in the center that has dimensions larger than the dimensions of the blanks 1, allowing the blanks 1 to pass through the through hole 19 with a given (relatively large) gap. According to Figures 6 to 9, the hopper 15 has a plurality of support brackets 20 designed to support the stack of blanks 1 (on all sides), which are arranged around the hole 19 and attached to the storage wall 18. In other words, the support brackets 20 pass through the hole 19 and define a passage that accommodates the stack of blanks 1 with minimal gaps. Furthermore, the hopper 15 has a plurality of retaining teeth 21 and 22 that protrude into the removal opening 16 and are attached to the storage wall 18 to prevent the blanks 1 from escaping. In other words, the retaining teeth 21 and 22 extend into the removal opening 16, reducing the passage of the removal opening 16 and holding the stack of blanks 1 within the hopper 15. The retaining teeth 21 and 22 therefore enable the unloading opening 16 to have dimensions smaller than the dimensions of the blank 1 so as to retain the blank 1 in the hopper 15 in the absence of operation of the unloading device. According to a preferred embodiment, the retaining teeth 21 and 22 are mounted on support brackets 20 which are in turn mounted on the receiving wall 18, i.e. each support bracket 20 is fixed directly to the receiving wall 18 support and then to the corresponding retaining tooth 21 and 22.

[0017] The hopper 15 is disposed in use in contact with the stack of blanks 1 and includes a reference element 23 for establishing a positional reference for a blank 1 in the stack of blanks 1; in particular, the reference element 23 establishes the position of the vertex 12 of each blank 1. That is, the positional reference established by the reference element 23 is configured to contact the same point on each blank 1 regardless of the type of blank 1. In particular, the reference element 23 has a triangular cross-section and has an upper vertex that establishes the positional reference and indirectly contacts the stack of blanks 1; that is, the vertex of the triangular cross-section of the reference element 23 directly contacts the vertex 12 of each blank 1 to establish the position of the vertex 12 of each blank 1. According to a preferred embodiment, the reference element 23 is mounted on the containing wall 18 and is therefore integral with the hopper 15.

[0018] As mentioned above, blanks 1 (all of the same structure, i.e., the same arrangement of panels and blades) are present to produce corresponding packaging materials with different die types (i.e., different sizes). Consequently, the supply unit 13 must be adjusted by means of a die type change operation (obviously involving the entire packaging machine) so that it can accommodate blanks 1 with a different die type. In other words, when a packaging machine has to produce packaging materials with a different die type (different size), it is necessary to stop the packaging machine, empty it of blanks 1 of the old die type, adjust the entire packaging machine (and therefore also the supply unit 13 of the packaging machine) to the new die type, and finally insert blanks 1 of the new die type. As a result, in order to contain blanks 1 having different mold types, the supply unit 13 can be adjusted by means of a mold type change operation, which involves changing the supply unit 13 from a first (old) configuration suitable for containing a first (old) mold type of blank 1 to a second (new) configuration suitable for containing a second (new) mold type of blank 1 different from the first (old) mold type.

[0019] The reference element 23 of the hopper 15, in use, contacts the stack of blanks 1 to establish a positional reference for the blanks 1 in the stack of blanks 1 (establishing the position of the apex 12 of each blank 1), and is in the same position relative to the frame 14 regardless of the type of blank 1, and therefore is not moved relative to the frame 14 due to a type change operation. In other words, at the end of all type change operations, the reference element 23 of the hopper 15 is always in the same position relative to the frame 14, and as a result, regardless of the type (size) of the blank 1, the apex 12 of each blank 1 is always in the same position relative to the frame 14.

[0020] 3, 4 and 10, the supply unit 13 comprises a reference element 24 having the same cross-sectional shape as the reference element 23, is aligned with the reference element 23 so as to establish the extension direction of the reference element 23, is separate and independent from the hopper 15 and the reference element 23, is arranged along the movement path P in the area of ​​the belt conveyor 17, is mounted on the frame 14 (just like the reference element 23) in the same position regardless of the type of blank 1 and is therefore not moved relative to the frame 14 for type change operations. In other words, during type change operations, all other adjustable elements of the supply unit 13 are moved relative to the frame 14, while the two reference elements 23 and 24 always remain in the same position relative to the frame 14 (naturally, excluding unavoidable tolerances). The reference element 23 is a (solid) extension of the reference element 24 inside the hopper 15, while from another point of view, the reference element 24 is a (solid) extension of the reference element 23 inside the conveyor 17.

[0021] According to different embodiments not shown here, reference elements 23 and 24 may be long enough so that reference element 23 also incorporates the functionality of reference element 24, or vice versa; in other words, the two reference elements 23 and 24 may constitute one inseparable housing instead of being separate and independent.

[0022] 2, the feeding unit 13 comprises a plurality of different interchangeable hoppers 15, each of which is associated with a corresponding mold type (size) of the blanks 1. In other words, an apparatus (kit) for the feeding unit 13 is provided, comprising a plurality of different interchangeable hoppers 15, each of which is associated with a corresponding mold type of the blanks 1. As a result, each hopper 15 is designed and adjusted to handle only a single corresponding mold type of the blanks 1, and therefore, during a mold type change operation, the old hopper 15 suitable for the old mold type (size) of the blanks 1 must be removed, and then a new hopper 15 suitable for the new mold type (size) of the blanks 1 must be installed.

[0023] To allow for rapid replacement of hoppers 15 during a mold type change operation, hoppers 15 are secured to frame 14 in a quickly removable manner (as a mold type change operation involves replacing an old hopper 15 associated with an old mold type with a new hopper 15 associated with a new mold type).

[0024] According to a preferred embodiment shown in Figures 3 and 4, the frame 14 comprises a support 25 with a seat designed to accommodate the hopper 15. In particular, the seat of the support 25 reproduces in a negative manner the (rectangular) shape of the accommodation wall 18 of the hopper 15, so that it accommodates the accommodation wall 18 inside, so that the support 25 is shaped like a rectangular frame in which the accommodation wall 18 of the hopper 15 is arranged.

[0025] The support 25 is movable on the frame 14 so as to move during a mold type change operation between a working position (shown in FIGS. 3 and 4) in which the hopper 15 housed in the support 25 is coupled to and aligned with the conveyor 17, and an exchange position (shown in FIG. 10) in which the hopper 15 housed in the support 25 is disconnected from and unaligned with the conveyor 17. In the exchange position (shown in FIG. 10), the hopper 15 housed in the support 25 is relatively far from the conveyor 17 and other components of the supply unit 13 and is therefore in an unobstructed space, which greatly facilitates both the operations performed to remove the old hopper 15 from the support 25 and the operations performed to install a new hopper 15 in the support 25. In particular, the frame 14 comprises two carriages 26 carrying the support 25 and two corresponding sliding guides 27 (oriented horizontally and vertically with respect to the path of movement P), along each of which the corresponding carriage 26 slides to move the support 25 between a working position (shown in Figures 3 and 4) and an exchange position (shown in Figure 10).

[0026] According to a preferred embodiment, the feed unit 13 is remotely electrically operable and comprises a locking device 28 which can be actuated to restrain the support 25 (carrying the hopper 15) to the frame 14 when the support 25 is in the working position (shown in FIGS. 3 and 4 ), i.e. the locking device 28 can be actuated to prevent the support 25 (carrying the hopper 15) from moving when the feed unit 13 is operating. By way of example, the locking device 28 can have a pneumatic actuation and can comprise a mushroom-shaped pin fixed to an edge of the support 25 and a servo-assisted clamping mechanism designed to clamp the pin to restrain the pin, and thus the support 25, to the frame 14.

[0027] Preferably, the support 25 has two upper seats 29 and two lower seats 30 (partially visible in FIG. 3 ), and each hopper 15 further comprises two pins 31 (better shown in FIG. 5 ) protruding from opposite ends of the containing wall 18 and configured to be inserted into the corresponding lower seats 30, and two latching mechanisms 32 (better shown in FIG. 5 and manually operated by means of respective levers) protruding from opposite ends of the containing wall 18 and configured to be inserted into the corresponding upper seats 29, and operable (by manually rotating the respective levers) to restrain the containing wall 18 to the support 25. The hopper 15 is coupled to the support 25 by first inserting only the two pins 31 into the corresponding lower seats 30 of the support 25, then rotating the hopper 15 about the pins 31 until the latching mechanisms 32 are inserted into the corresponding upper seats 29, and finally (manually) operating the latching mechanisms 32 to restrain the hopper to the support 25.

[0028] Preferably, the support 25 has a handle 33 that can be grasped by a user to push or pull the support 25 when it needs to be (manually) moved between the working position (shown in Figures 3 and 4) and the exchange position (shown in Figure 10). Similarly, each hopper 15 has a series of handles 34 that are fixed to the containing wall 18 of the hopper 15 and can be grasped by a user to manually handle the hopper 15. To make the hopper 15 lighter and therefore easier to manually manipulate the hopper 15, the containing wall 18 has a series of weight-reducing perforations, and furthermore the containing wall 18 is generally made from a lightweight and durable material, such as an aluminum alloy or a composite material (e.g., a carbon fiber-based material).

[0029] 10, the conveyor 17 comprises three motor-driven conveyor belts 35, parallel and adjacent to one another along the travel path P, mounted on the frame 14 and positioned below the blank 1 to support it. Each conveyor belt 35 comprises a belt loop around two end pulleys, one of which is an idle pulley, while the other end pulley is motor-driven and receives motion from a corresponding electric motor. Preferably, the conveyor belts 35 have independent electric motors, i.e., each conveyor belt 35 is driven by its own independent electric motor; in this way, the travel speeds of the three conveyor belts 35 can be adjusted in a differentiated manner.

[0030] According to a preferred embodiment, each conveyor belt 35 is movably mounted on the frame 14 so as to move during the mold type change operation along at least two adjustment directions D1 and D2 which are perpendicular to each other and perpendicular to the movement path P, in particular the adjustment direction D1 being horizontal and the other adjustment direction D2 being vertical.

[0031] According to a preferred embodiment, for each conveyor belt 35, the conveyor 17 comprises (at least) a carriage (indirectly) supporting the conveyor belt 35, a slide guide (typically consisting of two parallel rods) oriented parallel to the adjustment direction D1 and along which the carriage slides to move the conveyor belt 35, and in particular an electric motor (i.e., an electrically controlled actuator) controlling the movement of the carriage along the slide guide, for example mechanically coupled to the carriage by means of a screw-nut screw connection (the screw is rotated by the electric motor and thus determines the axial translation of the nut screw that engages with the screw and is integral with the carriage). A further screw-nut screw connection is attached to the carriage, the screw oriented along the vertical adjustment direction D2 being rotated by a further electric motor and thus determining the axial translation of the nut screw that engages with the screw and supports the conveyor belt 35.

[0032] According to a preferred embodiment, the entire conveyor 17 (i.e., the three conveyor belts 35 with all corresponding mechanisms for translation along the two adjustment directions D1 and D2) is movably mounted on the frame 14 so as to move during a mold type change operation between a working position (shown in FIG. 3 ), in which the conveyor 17 is coupled to the hopper 15, and an exchange position (shown in FIG. 10 ), in which the conveyor 17 is decoupled and at a given distance from the hopper 15; in particular, the movement of the conveyor 17 between the working position (shown in FIG. 3 ) and the exchange position (shown in FIG. 10 ) is performed through horizontal translation parallel to the movement path P (and therefore perpendicular to the adjustment directions D1 and D2). The main purpose of the movement of the conveyor 17, which is only performed during a mold type change, is to move the conveyor 17 away from the hopper 15 so as to release any possible coupling between the conveyor 17 and the hopper 15, thus allowing the support 25 (carrying the hopper 15) to slide. A further purpose of the movement of the conveyor 17, which is only performed during a mold type change, is to move the conveyor 17 away from the hopper 15 in order to create more free space around the hopper 15 and thus make it easier to change the hopper 15.

[0033] According to a preferred embodiment shown in FIG. 11, the supply unit 13 comprises two carriages 36 supporting the entire conveyor 17 (i.e., three conveyor belts 35 with all the corresponding mechanisms for translational movement along the two adjustment directions D1 and D2), and two sliding guides 37 oriented parallel to the movement path P and along which the carriages 36 slide in order to move the entire conveyor 17 between the work position (shown in FIG. 3) and the exchange position (shown in FIG. 10), in particular an electric motor (i.e., an electrically controlled actuator) controlling the movement of the carriages 36 along the sliding guides 37, which is mechanically coupled to the carriages 36, for example via a screw-nut screw connection (the screw is rotated by the electric motor, thus determining the axial translation of the nut screw engaging the screw, and is integrated into one of the carriages 36).

[0034] According to Figure 6, the hopper 15 comprises (at least) a support bracket 20 protruding towards the corresponding conveyor belt 35 of the conveyor 17, supports the stack of blanks 1 along the end segment of the movement path P, and has a "U" shape defining a seat 38 at its centre into which the end of the conveyor belt 35 is inserted. The movement of the conveyor 17 only takes place during a mould change, allowing the corresponding conveyor belt 35 to move away from the seat 38, thereby allowing the support 25 (carrying the hopper 15) to continue sliding.

[0035] 8 and 9, the hopper 15 supports a number of fixed retaining teeth 21 which project into the discharge opening 16 to prevent the blanks 1 from escaping, the fixed retaining teeth 21 being mounted in a fixed position, i.e. so as not to be subject to any kind of movement.

[0036] 8 and 9, the hopper 15 also supports three movable retaining teeth 22 which protrude into the removal opening 16 to prevent the blank 1 from escaping through the removal opening 16, and unlike the fixed retaining teeth 21 (which do not move in any way and always remain in the same position), each movable retaining tooth 22 is mounted to move between an ejection position (shown in the accompanying figures) in which it protrudes a large amount into the removal opening 16, and a retracted position (not shown) in which it protrudes a small amount into the removal opening 16.

[0037] In particular, for each movable holding tooth 22 there is a resilient element 39 which urges the holding tooth towards the removal position (shown in the accompanying drawings), and each movable holding tooth 22 is associated with a position sensor 40 which is configured to detect the position of the movable holding tooth 22. The supply unit 13 comprises a control unit 41 (schematically shown in FIG. 9) which is configured to adjust the movement speed of the conveyor 17 (i.e. the conveyor belt 35 of the conveyor 17) depending on the readings received from the position sensor 40. In particular, the control unit 41 is configured to adjust the movement speed of the conveyor belt 35 so that the movable holding teeth 22 move in a synchronous motion (i.e. move in a predetermined desired time sequence) during removal of the blank 1. For example, if the right-hand movable holding tooth 22 moves with excessive lead / lag relative to the other holding teeth 22 during removal of the blank 1, the right-hand conveyor belt 35 is slowed / accelerated.

[0038] Next, a mold type change operation for changing the supply unit 13 from an old configuration suitable for containing an old type (size) of blank material 1 to a new configuration suitable for containing a new type (size) of blank material 1 will be described.

[0039] First, the packaging machine is stopped, then the supply unit 13 is also stopped, and when the supply unit 13 is stopped, the old blanks 1 are removed from the supply unit 13, and when the supply unit 13 is empty (i.e. there are no blanks 1), the conveyor 17 is moved (by the action of the corresponding electric motor) from the working position (shown in Figure 3) to the replacement position (shown in Figure 10).

[0040] Only when the conveyor 17 is in the exchange position (shown in FIG. 10) can the locking device 28 operate to release (disengage) the support 25 (carrying the old hopper 15) from the frame 14. At this point, the operator manually slides the support 25 from the working position (shown in FIGS. 3 and 4) to the exchange position (shown in FIG. 10), and when the support 25 is in the exchange position (shown in FIG. 10), the operator can remove the old hopper 15 associated with the old mold type (size) of the blank 1 from the support 25 and then install the new hopper 15 associated with the new mold type (size) of the blank 1 onto the support 25.

[0041] Typically, at this point (but this can also happen before or after), the control unit 41 changes the position of the conveyor belt 35 of the conveyor 17 along the adjustment directions D1 and D2 (using the corresponding electric motors) so as to adjust the position of the conveyor belt 35 to the new mold type (size) of the blank 1.

[0042] Upon completion of the replacement of the hopper 15 and the adjustment of the conveyor belt 35 of the conveyor 17, the operator can manually slide the support 25 from the replacement position (shown in FIG. 10) to the working position (shown in FIGS. 3 and 4), and when the support 25 is in the working position (shown in FIGS. 3 and 4), the locking device 28 is operated to restrain (lock) the support 25 (carrying the new hopper 15) to the frame 14. Only when the support 25 is restrained to the frame 14 in the working position (shown in FIGS. 3 and 4), can the conveyor 17 be moved (by the action of the corresponding electric motor) from the replacement position (shown in FIG. 10) to the working position (shown in FIG. 3).

[0043] Finally, blanks 1 of the new mold type are loaded into the supply unit 13, completing the mold type change operation.

[0044] As noted above, during all mold type change operations, both reference elements 23 and 24 remain in the same position relative to frame 14, i.e., do not change the position of the position reference established by them relative to frame 14 (obviously, net of unavoidable constructional tolerances). In particular, although reference element 23 is replaced (as it is attached to hopper 15), the position of reference element 23 relative to frame 14 does not change when switching from an old hopper 15 to a new hopper 15 (i.e., reference element 23 on the new hopper 15 is in exactly the same position as reference element 23 on the old hopper 15). Reference element 24 may or may not be replaced (to adjust its shape to accommodate differences in the shape of the blank 1), but even in the case of replacement of reference element 24, the position of reference element 24 does not change during the replacement (i.e., new reference element 24 is in exactly the same position as old reference element 24).

[0045] In the preferred embodiment shown in the accompanying drawings, the conveyor 17 is active, i.e. has a motor-driven element (conveyor belt 35) that pushes the blank 1 along the movement path P, while according to a different embodiment the conveyor 17 is passive, i.e. has no motor-driven element and uses only gravity to push the blank 1 along the movement path P (which must obviously be inclined relative to the horizontal).

[0046] In a preferred embodiment shown in the accompanying drawings, the packing machine produces packaging for coffee capsules. According to other embodiments not shown here, the packing machine produces packaging for food products, smoking products, personal hygiene products or other products.

[0047] The embodiments described herein can for this reason be combined with one another without exceeding the scope of protection of the present invention.

[0048] The above-described supply unit 13 has a number of advantages. First, the above-described supply unit 13 significantly reduces the reconfiguration time required to adjust to a new mold type (size) of the blank 1, i.e., the above-described supply unit 13 minimizes the time required to perform a mold type change, which involves changing the supply unit 13 from an old configuration suitable for accommodating the old mold type (size) of the blank 1 to a new configuration suitable for accommodating the new mold type (size) of the blank 1.

[0049] This result is achieved thanks to the fact that there are several different interchangeable hoppers 15, each associated with a corresponding mold type (size) of the blank 1, so that during a mold type change operation the entire hopper 15 is completely exchanged and the new hopper 15 installed is completely set up and adjusted to the corresponding mold type (size) of the blank 1 without the need for any additional adjustments.

[0050] This result is further achieved by the fact that the hopper 15 has a reference element 23 which, in use, is placed in contact with the stack of blanks 1, establishing a positional reference for the blanks 1 relative to the frame 14 regardless of the type (size) of the blanks 1, and therefore is not moved relative to the frame 14 due to a type change operation. The presence of the reference element 23 ensures that every time the hopper 15 is replaced, the new hopper 15 will find the blanks 1 in a pre-known position, and therefore all adjustments previously made to the hopper 15 are still fully valid and do not need to be changed (updated).

[0051] As a result, a mould type change operation only requires the exchange of the hopper 15 (which can be carried out in a few minutes thanks to the particular structure of the hopper 15), but other adjustments must be made to the holding teeth 21 and 22 (which are holding elements arranged in the area of ​​the removal opening 16), since each hopper 15 (and therefore its holding teeth 21 and 22) is associated with (and therefore already adjusted to) one corresponding mould type (size) of the blank 1.

[0052] Furthermore, the above-described supply unit 13 does not require complex mechanical parts and is therefore simple and economical to manufacture.

[0053] The invention has also been found to be advantageous in the use of a method for performing a mould type change in a supply unit 13, in particular for adjusting the supply unit 13 from a first mould type of blanks 1 to a second mould type of blanks 1. The method preferably comprises the step of changing the configuration of the supply unit 13 while keeping the first reference element 23 in the same position relative to the frame 14 at the end of the configuration change step. The method preferably comprises the steps of removing a first hopper 15 associated with the first mould type of blanks 1 and then installing a second hopper 15 different from the first hopper 15 and associated with the second mould type of blanks 1. The present invention has the following aspects (configurations). [Aspect 1] A supply unit (13) for supplying blanks (1) in a packaging machine, comprising: A frame (14); a hopper (15) supported by the frame (14), the hopper (15) being designed to hold a stack of blanks (1) and having a removal opening (16) through which one blank (1) at a time can be removed from the stack of blanks (1); a conveyor (17) supported by the frame (14) for moving the blanks (1) along a moving path (P) that ends in the hopper (15); a supply unit (13) that can be adjusted to contain blanks (1) having different mold types by a mold type change operating means, the change operating means involving changing the supply unit (13) from a first configuration suitable for containing a first mold type of the blanks (1) to a second configuration suitable for containing a second mold type of the blanks (1); The hopper (15) is provided with a first reference element (23), which, during use, is positioned in contact with the stack of blanks (1) to establish a positional reference for the blanks (1) in the stack of blanks (1), and which is in the same position relative to the frame (14) regardless of the mold type of the blanks (1), thereby not moving relative to the frame (14) due to a mold type change operation. [Aspect 2] A supply unit (13) according to aspect 1, wherein the position reference established by the first reference element (23) is configured to contact the same point on each blank (1) regardless of the type of blank (1). [Aspect 3] Each blank (1) is Two vertical creases (2) and A plurality of horizontal fold lines (3) defining a plurality of panels (4 to 7) between the two vertical fold lines (2); Two first wings (10) connected to the first longitudinal fold line (2); two second wings (11) connected to the second longitudinal fold line (2); the two first wings (10) define between them a triangular void space having a vertex (12) in the region of the first longitudinal fold line (2); The first reference element (23) is arranged and shaped so that the position reference is located in the region of the apex of the empty space (12) defined between the two first blades (10). [Aspect 4] 4. The supply unit (13) of claim 1, 2 or 3, wherein the first reference element (23) has a triangular cross-section and an upper apex that establishes the position reference and is in direct contact with the stack of blanks (1). [Aspect 5] A supply unit (13) according to any one of aspects 1 to 4, wherein the first reference element (23) is integral with the hopper (15). [Aspect 6] The supply unit (13) according to any one of aspects 1 to 5, further comprising a second reference element (24), the second reference element (24) being aligned with the first reference element (23) so as to establish an extension direction of the first reference element (23), the hopper (15) and the first reference element (23) being separate and independent, being arranged along the movement path (P) in the area of ​​the conveyor (17), and being mounted on the frame (14) at the same position regardless of the mold type of the blank (1), thereby not moving relative to the frame (14) due to a mold type changing operation. [Aspect 7] a plurality of different interchangeable hoppers (15) are provided, each hopper (15) being associated with a corresponding die type of said blank (1); A supply unit (13) according to any one of aspects 1 to 6, wherein each hopper (15) is removably secured to the frame (14) so ​​as to be exchanged during a mold type change operation, the mold type change operation involving exchanging a first hopper (15) associated with the first mold type with a second hopper (15) associated with the second mold type. [Aspect 8] Aspect 8. The supply unit (13) according to aspect 7, wherein the frame (14) comprises a support (25) having a seat designed to accommodate the hopper (15). [Aspect 9] The supply unit (13) of aspect 8, wherein the support (25) is movable on the frame (14) and moves between a working position where the hopper (15) housed in the support (25) is coupled to and aligned with the conveyor (17) during a mold type change operation, and an exchange position where the hopper (15) housed in the support (25) is separated from and unaligned with the conveyor (17). [Aspect 10] The frame (14) comprises at least one first carriage (26) carrying the support (25); A supply unit (13) according to aspect 9, comprising a first, in particular horizontally oriented, sliding guide (27), along which the first carriage (26) slides to move the support (25) between the working position and the replacement position. [Aspect 11] A supply unit (13) according to aspect 9 or 10, comprising a locking device (28) operable to lock the support (25) to the frame (14) when the support (25) is in the working position. [Aspect 12] The support (25) has two upper seats (29) and two lower seats (30), Each hopper (15) is provided with two pins (31) configured to be inserted into a corresponding lower seat (30); A supply unit (13) according to any one of aspects 8 to 11, wherein each hopper (15) is configured to be inserted into a corresponding upper seat (29) and includes two latching mechanisms (32) that function to latch the hopper (15) to the support (25). [Aspect 13] 13. The supply unit (13) of any one of aspects 1 to 12, wherein each hopper (15) has a series of handles (34) that are grasped by an operator to manually move the hopper (15). [Aspect 14] the conveyor (17) comprises at least one conveyor belt (35), the at least one conveyor belt (35) being attached to the frame (14) and positioned below the blank (1) to support the blank (1); A supply unit (13) according to any one of aspects 1 to 13, wherein the conveyor belt (35) is movably mounted on the frame (14) and moves during a mold format change operation along at least one adjustment direction (D1) perpendicular to the movement path (P), preferably along two adjustment directions (D1, D2) perpendicular to each other and perpendicular to the movement path (P). [Aspect 15] The conveyor (17) at least one second carriage carrying said conveyor belt (35); a second slide guide that is parallel to the adjustment direction (D1) and along which the second carriage slides to move the conveyor belt (35); 15. The supply unit (13) according to embodiment 14, comprising: [Aspect 16] The supply unit (13) according to any one of aspects 1 to 15, wherein the conveyor (17) is movably attached to the frame (14) and moves between a working position where it is connected to the hopper (15) and an exchange position where it is not connected and is at a certain distance from the hopper (15) during a mold type change operation. [Aspect 17] A supply unit (13) as described in aspect 16, wherein the hopper (15) comprises a support bracket (20) that protrudes toward the conveyor belt (35) of the conveyor (17), supports a stack of the blanks (1) along the end segment of the movement path (P), and has a "U" shape that defines a seat (38) at its center into which the leading end of the conveyor belt (35) is inserted. [Aspect 18] the hopper (15) supports at least two movable retaining teeth (22) projecting into the discharge opening (16) to prevent the blanks (1) from escaping through the discharge opening (16); each movable retaining tooth (22) is movable between a dispensed position in which it projects into said dispense opening (16) to a greater extent and a retracted position in which it projects into said dispense opening (16) to a lesser extent; For each movable retaining tooth (22) there is provided a resilient element (39) which urges said movable retaining tooth towards the removal position, Each movable retainer tooth (22) is associated with a position sensor (40) configured to detect the position of said movable retainer tooth (22); 18. The supply unit (13) according to any one of aspects 1 to 17, further comprising a control unit (41) configured to adjust the speed of movement of the conveyor (17) depending on information received from the position sensor (40). [Aspect 19] The conveyor (17) comprises at least two conveyor belts (35) which are independent and parallel to each other; A supply unit (13) as described in aspect 18, wherein the control unit (41) is configured to adjust the movement speeds of the two conveyor belts (35) so that the two movable holding teeth (22) move synchronously during removal of the blank material (1). [Aspect 20] A feed assembly (13) as described in any one of aspects 1 to 19, wherein the hopper (15) supports a plurality of fixed retaining teeth (21) that protrude into the discharge opening (16) to prevent the blank (1) from slipping out. [Aspect 21] The hopper (15) a containment wall (18) that is perforated at its center so as to be crossed by the stack of blanks (1); a plurality of support brackets (20) configured to support the stack of blanks (1) and attached to the containment wall (18); a plurality of retaining teeth (21, 22) projecting into the removal opening (16) to prevent the blank (1) from slipping out, attached to the receiving wall (18) and in particular connected to the support bracket (20); The supply unit (13) according to any one of aspects 1 to 20, comprising: [Aspect 22] A method for performing a die type change in a supply unit (13) according to any one of aspects 1 to 21 to adjust the supply unit (13) from a first die type of the blanks (1) to a second die type of the blanks (1), comprising: At the end of a mould type change, the method comprises the step of changing the configuration of the supply unit (13) which holds the reference element in the same position relative to the frame (14). [Aspect 23] The supply unit (13) according to one or more of aspects 1 to 21; a packaging unit that receives a single blank (1) from the supply unit (13) and folds the blank (1); A packaging machine comprising: [Aspect 24] 22. An apparatus for the supply unit (13) according to one or more of aspects 1 to 21, comprising: The apparatus comprises a plurality of different interchangeable hoppers (15), each hopper (15) associated with a corresponding type of blank (1). [Explanation of symbols]

[0054] 1 blank material 2 Vertical fold lines 3 Horizontal fold line 4 Panels 5 Panel 6 Panels 7 Panels 8 Panels 9 Lid 10 Feathers 11 Feather 12 Vertices 13 Supply Unit 14 frames 15 Hopper 16. Removal opening 17 Belt conveyor 18 Containment Wall 19 Through hole 20 Support bracket 21 Fixed retainer teeth 22 Movable retainer teeth 23 Criteria Elements 24 Criteria Elements 25 Support 26 Carriage 27 Slide Guide 28 Locking device 29 The top seat 30 Lower Seat 31 pin 32 Latching mechanism 33 Handle 34 Handle 35 Conveyor Belt 36 Carriage 37 Slide Guide 38 Seat area 39 Elastic Elements 40 Position Sensor 41 Control Unit P Movement route D1 Adjustment direction D2 Adjustment direction

Claims

1. A feeding unit (13) for feeding blanks (1) in a packaging machine, comprising: A frame (14); a hopper (15) supported by the frame (14), the hopper (15) being designed to hold a stack of blanks (1) and having a removal opening (16) through which one blank (1) at a time can be removed from the stack of blanks (1); a conveyor (17) supported by the frame (14) for moving the blanks (1) along a path of movement (P) that ends in the hopper (15); To accommodate blanks (1) having different mould types, the supply unit (13) can be adjusted by a mould type change operating means, which involves changing the supply unit (13) from a first configuration suitable for accommodating a first mould type of the blanks (1) to a second configuration suitable for accommodating a second mould type of the blanks (1); the hopper (15) is provided with a first reference element (23), which, in use, is placed in contact with the stack of blanks (1) to establish a positional reference for the blanks (1) in the stack of blanks (1), and which is in the same position relative to the frame (14) regardless of the type of the blanks (1), and thereby does not move relative to the frame (14) for a type-type change operation; Each blank (1) is Two vertical creases (2), a plurality of horizontal fold lines (3) defining a plurality of panels (4-7) between the two vertical fold lines (2); two first wings (10) connected to the first longitudinal fold line (2); two second wings (11) connected to the second longitudinal fold line (2); the two first wings (10) define between them a triangular void space having a vertex (12) in the region of the first longitudinal crease line (2); The first reference element (23) is arranged and shaped so that the position reference is located in the region of the apex (12) of the free space defined between the two first blades (10).

2. 2. The supply unit (13) of claim 1, wherein the position reference established by the first reference element (23) is configured to contact the same point on each blank (1) regardless of the type of the blank (1).

3. 3. A supply unit (13) according to claim 1 or 2, wherein the first reference element (23) has a triangular cross-section and has an upper apex that establishes the position reference and is in direct contact with the stack of blanks (1).

4. A feeding unit (13) according to any one of claims 1 to 3, wherein said first reference element (23) is integral with said hopper (15).

5. 5. The supply unit (13) according to claim 1, further comprising a second reference element (24) which is aligned with the first reference element (23) so as to establish an extension direction of the first reference element (23), the hopper (15) and the first reference element (23) being separate and independent, arranged along the movement path (P) in the area of ​​the conveyor (17), and mounted on the frame (14) at the same position regardless of the type of the blank (1), so that the supply unit (13) does not move relative to the frame (14) during a type type change operation.

6. a plurality of different interchangeable hoppers (15) are provided, each hopper (15) being associated with a corresponding die type of said blank (1); 6. The supply unit (13) of claim 1, wherein each hopper (15) is removably secured to the frame (14) so ​​as to be exchanged during a mould type change operation, the mould type change operation involving exchanging a first hopper (15) associated with the first mould type for a second hopper (15) associated with the second mould type.

7. 7. A supply unit (13) according to claim 6, wherein the frame (14) comprises a support (25) having a seat designed to accommodate the hopper (15).

8. The supply unit (13) according to claim 7, wherein the support (25) is movable on the frame (14) and moves between a working position where the hopper (15) housed in the support (25) is coupled to and aligned with the conveyor (17) during a mold type change operation, and an exchange position where the hopper (15) housed in the support (25) is separated from and unaligned with the conveyor (17).

9. The frame (14) comprises at least one first carriage (26) carrying the support (25); 9. The supply unit (13) of claim 8, further comprising a first horizontally oriented slide guide (27) along which the first carriage (26) slides to move the support (25) between the working position and the exchange position.

10. 10. A supply unit (13) according to claim 8 or 9, comprising a locking device (28) operable to lock the support (25) to the frame (14) when the support (25) is in the working position.

11. The support (25) has two upper seats (29) and two lower seats (30), Each hopper (15) is provided with two pins (31) configured to be inserted into a corresponding lower seat (30); A supply unit (13) according to any one of claims 7 to 10, wherein each hopper (15) is configured to be inserted into a corresponding upper seat (29) and comprises two latching mechanisms (32) that function to lock the hopper (15) to the support (25).

12. A feeding unit (13) according to any one of the preceding claims, wherein each hopper (15) has a series of handles (34) which are grasped by an operator to manually move said hopper (15).

13. the conveyor (17) comprises at least one conveyor belt (35), the at least one conveyor belt (35) being attached to the frame (14) and positioned below the blank (1) to support the blank (1); The supply unit (13) according to any one of claims 1 to 12, wherein the conveyor belt (35) is movably mounted on the frame (14) and moves during a mould type change operation along two adjustment directions (D1, D2) that are perpendicular to each other and perpendicular to the movement path (P).

14. The conveyor (17) at least one second carriage carrying said conveyor belt (35); a second slide guide that is parallel to the adjustment direction (D1) and along which the second carriage slides to move the conveyor belt (35); 14. A supply unit (13) according to claim 13, comprising:

15. The supply unit (13) according to any one of claims 1 to 14, wherein the conveyor (17) is movably attached to the frame (14) and moves between a working position where it is connected to the hopper (15) and an exchange position where it is not connected and is at a certain distance from the hopper (15) during a mold type change operation.

16. 16. A supply unit (13) according to claim 15, wherein the hopper (15) comprises a support bracket (20) which projects towards the conveyor belt (35) of the conveyor (17) and supports the stack of blanks (1) along the end segment of the movement path (P), and which has a "U" shape defining a seat (38) in its centre into which the leading end of the conveyor belt (35) is inserted.

17. the hopper (15) supports at least two movable retaining teeth (22) projecting into the discharge opening (16) to prevent the blank (1) from escaping through the discharge opening (16); each movable retaining tooth (22) is movable between a dispensed position in which it projects to a greater extent into said dispense opening (16) and a retracted position in which it projects to a lesser extent into said dispense opening (16); For each movable retaining tooth (22) there is provided a resilient element (39) which urges said movable retaining tooth towards the removal position, Each movable retainer tooth (22) is associated with a position sensor (40) configured to detect the position of said movable retainer tooth (22); A supply unit (13) according to any one of claims 1 to 16, further comprising a control unit (41) configured to adjust the speed of movement of the conveyor (17) depending on information received from the position sensor (40).

18. The conveyor (17) comprises at least two conveyor belts (35) which are independent and parallel to each other; 18. The feeding unit (13) according to claim 17, wherein the control unit (41) is configured to adjust the speed of movement of the two conveyor belts (35) so that the two movable holding teeth (22) move synchronously during removal of the blanks (1).

19. A supply unit (13) according to any one of claims 1 to 18, wherein the hopper (15) supports a plurality of fixed holding teeth (21) projecting into the removal opening (16) to prevent the blanks (1) from slipping out.

20. The hopper (15) a containing wall (18) that is perforated at its center so as to be crossed by the stack of blanks (1); a plurality of support brackets (20) configured to support the stack of blanks (1) and attached to the containing wall (18); a plurality of retaining teeth (21, 22) protruding into the removal opening (16) to prevent the blank (1) from slipping out, attached to the receiving wall (18) and connected to the support bracket (20); A supply unit (13) according to any one of the preceding claims, comprising:

21. 21. A method for performing a mould type change in a feed unit (13) according to any one of claims 1 to 20, for adjusting the feed unit (13) from a first mould type of the blanks (1) to a second mould type of the blanks (1), comprising: At the end of a mould type change, the method comprises the step of changing the configuration of the supply unit (13) which holds the reference element in the same position relative to the frame (14).

22. The supply unit (13) according to any one of claims 1 to 20, a packaging unit that receives a single blank (1) from the supply unit (13) and folds the blank (1); A packaging machine comprising:

23. An arrangement for the supply unit (13) according to any one of claims 1 to 20, comprising: The apparatus comprises a plurality of different interchangeable hoppers (15), each hopper (15) associated with a corresponding type of said blank (1).

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