EP3362274B1

EP3362274B1 - Folding unit, forming machine and method for folding

Info

Publication number: EP3362274B1
Application number: EP16801562.6A
Authority: EP
Inventors: Pierpaolo CALDERONI
Original assignee: Teco SRL
Current assignee: Teco SRL
Priority date: 2015-10-14
Filing date: 2016-10-12
Publication date: 2019-09-04
Anticipated expiration: 2036-10-12
Also published as: WO2017064630A1; HRP20191752T1; PL3362274T3; ITUB20154680A1; EP3362274A1; PT3362274T; RS59620B1; ES2752562T3

Description

The present invention relates to a forming machine. In particular, the present invention relates to a forming machine for forming trays made of cardboard or similar materials. In more detail, the present invention relates to a forming machine for forming cardboard trays provided with reinforced corners or produced with similar materials.

BACKGROUND TO THE INVENTION

In the field of industrial production of trays with reinforced corners, the use is well known of forming machines provided with one or more folding stations for folding flat die-cut panels made of cardboard or other similar materials, wherein each stations provided with a respective folding unit. The reinforced corners are obtained by folding folds of the panels that are adequately shaped and usually have weakening lines; the folding operation is performed by using (folding) bars arranged along a panel feeding path where they operate in a direction transverse or parallel to the feeding direction, with the panel usually (although without limitation) stopped in the corresponding folding station, moved by means of an actuating device with respect to the frame of the folding unit. This device is provided with an interface (movable with respect to the frame) supporting the bar. In particular, assuming that the bars are arranged parallel to the panel feeding direction, the folding step is performed, as well known, along a trajectory transverse to the panel feeding direction, by actuating these bars in succession through a pair of linear actuating devices (of the fluid-dynamic type or activated in any other way), each of which moves, directly or indirectly, the bar transversally to the panel feeding direction. In particular, a first actuator is carried by the interface and carries the bar, and a second actuator activates the interface with respect to the frame. A folding unit with the features of the preamble of claim 1 is known from US 4 022 116 .
In the industry, it is usual to receive orders for the production of trays of different format to be produced in succession, with reinforced corners of different dimensions (to which correspond flaps and weakening lines of different dimensions), produced by using panels made of different materials and thickness that have, therefore, different elastic features and therefore different mechanical reactions to the folding operations. Therefore, time and care are necessary in order to set the strokes of the first and of the second actuators by expert operators, who will adjust the stroke of the two actuators just by means of repeating attempts.
Moreover, if the trays to be formed are asymmetrical in shape, it is necessary to double the actuating devices with which the folding unit is provided, and therefore it is necessary to furthermore complicate the step of adjusting the machine members destined to the folding of the flaps of the die-cut panels.
In view of the above description, the problem of forming trays by means of a forming machine provided with folding units of simple conformation, equipped with few actuation elements and practical to be used in the format change operations and to manage panels of asymmetrical conformation is still unsolved, and represents an interesting challenge for the Applicant, who wants to modify the market of forming machines to its own benefit.
In view of the above description, it would be desirable to have available a folding unit for a machine for forming trays with reinforced corners that, in addition to allow limiting and possibly overcoming the drawbacks of the prior art, is easy to be used and defines a new standard in the industry, is reliable over the time, is easy to be maintained, and require minimal transport and recovery costs.

SUMMARY OF THE PRESENT INVENTION

The present invention relates to a forming machine. In particular, the present invention relates to a forming machine for forming trays made of cardboard or similar materials. In more detail, the present invention relates to a forming machine for forming cardboard trays provided with reinforced corners or produced with similar materials.
An object of the present invention is to provide a folding unit for folding die-cut panels, that is provided with at least one folding bar actuatable by means of an actuating device comprising at least two linear actuating members, is easily to be adjusted in order to control the movement of the at least one bar along so optimized paths that the folding of the flaps of each die-cut panel can be easily adjusted and repeated, in order to solve the drawbacks described above and to satisfy a plurality of requirements that to date have still not been addressed; therefore, a folding unit capable to represent a new and original source of economic interest for the Applicant.
According to the present invention it is provided a folding unit for die-cut panels with the features of claim 1.
According to the present invention it is also provided a forming machine comprising a folding unit as described above.
A further object of the invention is to provide a method for folding die-cut panels by using a folding unit as described above.
According to the invention, a folding group is provided comprising a frame that extends along a given direction and supports a first folding bar directed according to said direction through the interposition of an actuating unit designed to move said first bar along a curvilinear trajectory transverse to said given direction to fold flaps of a die-cut panel; said actuating unit comprising a first actuating device and a second actuating device carried by said frame and associated with said first bar to move this latter along said trajectory; said first actuating device being provided with a first transmission actuated by means of a first rotary motor mechanically coupled to said first bar to move this latter with a rectilinear motion; said first transmission comprising a first flexible member mechanically coupled to said first rotary motor through a first pulley.
According to a variant of the invention, said first actuating device of said folding unit comprises a first support member, provided with rectilinear guiding means directed transversally to said given direction, and a first slide, coupled to said rectilinear guiding means in a freely sliding manner; said first slide carrying said first bar through a first bracket coupled to said first flexible member so as to be movable with respect to said first support member through said first rotary motor.

BRIEF DESCRIPTION OF DRAWINGS

Further characteristics and advantages will be more apparent from the description below, set forth with reference to the attached drawings, that illustrate some examples of embodiment, where identical or corresponding parts of the system are identified by the same reference numbers. In particular:

figure 1 is a schematic perspective view of a folding unit of a forming machine for forming trays provided with reinforced corners according to the present invention;
figure 2 is a schematic perspective view of a portion of figure 1, in enlarged scale and with some parts removed for the sake of clarity;
figure 3 is a schematic perspective view of figure 2, rotated by 90° and in enlarged scale;
figure 4 is a schematic perspective view of figure 1, in enlarged scale and with some parts removed for the sake of clarity; and
figure 5 is a plan view of a panel that can be processed by means of the folding unit of figure 1;
figure 6 is a schematic perspective view of an example of tray provided with reinforced corners that can be produced by means of the unit of figure 1; and
figures 7a)-7b) are plan views of some examples of reinforced corners that can be produced by means of the unit of figure 1.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

In figure 1, number 100 indicates, in its entirety, a forming machine for forming trays with reinforced corners that is provided with a frame 101 and with a folding station 110. The machine 100 comprises (in this station 110) a folding unit 1 that can be used to fold flaps L of flanks F of die-cut panels P, a specimen of which can be seen only in figure 5, to be transformed in the reinforced corners of a tray V, a specimen of which is shown only in figure 6, where the respective corners may be any one of the three types A, A' and A" of prismatic corners, a plan view of which is shown only in figures 7a)-7b). In particular, in these figures the first two specimens of corners A and A' have triangular cross-section and the third corner A" has L-shaped cross-section, all the three corners being produced by folding a flap L provided with two weakening lines I on a respective flank F, according to three different ways of forming the respective folding steps, but always according to trajectories T transverse to the direction D.
The unit 1 comprises a frame 10, delimited, transversally to the direction D, by two side portions 11 and 13 that are arranged transversally to the direction D and are better shown in figure 4 and are connected together through beams 14 and 15, aligned with the direction D and better shown in figure 4. The frame 10 is carried vertically sliding (in figure 1) by means of two slide- guide devices 16 and 17, one for each side portion 11 and 13, and engages the folding station 110.
With particular reference to figure 2, the frame 10 furthermore supports at least one folding bar 22 directed according to the direction D through the interposition of an actuating unit 20 designed to move the first bar 22 along a curvilinear trajectory T to fold flaps L of a die-cut panel P. The actuating unit 20 comprises a first actuating device 24 and a second actuating device 26 carried by the frame 10 and associated with the first bar 22 in order to move this latter so as to generate the trajectory T, which is transverse to the direction D and is schematically shown in figure 2 with a dot dash line. As it is known, each plane curvilinear motion can be subdivided into segments, each of which can be generated by composing adequately modulated rectilinear displacements.
With particular reference to figure 2, the first actuating device 24 is provided with a first transmission 240 comprising a first flexible member 242 mechanically coupled to a first rotary motor 244 through a first pulley 246 and mechanically coupled to the first bar 22 in order to move this latter with rectilinear motion, as it will be better explained below.
The first device 24 comprises a first support member 241 provided with a rectilinear guide 2410 directed transversally to the given direction D and a first slide 2412 coupled to the rectilinear guide 2410 in a freely sliding manner. The first slide 2412 carries the first bar 22 through a first bracket 220 coupled to the first flexible member 242 so as to be movable with respect to the first support member 241 through the first rotary motor 244. With reference to figure 2 again, the first flexible member 242 is annular in shape and has a first and a second transport branches 2421 and 2422 that are parallel to the first rectilinear guide 2410, and the first bracket 220 is rigidly coupled to the first transport branch 2421 of the first flexible member 242.
The first support member 241 has an elongated portion 2414 arranged transversally to the first rectilinear guide 2410, and in particular vertically in figure 1. The elongated portion 2414 is coupled in a sliding manner transversally to the given direction D through a slide-guide device 30; the second device 26 is designed to move the elongated portion 2414 longitudinally with respect to the frame 10 transversally to the first device 24.
With reference to figure 2, the second device 26 comprises a second rotary motor 260 carried by the frame 10 and a second transmission 262 provided with a second flexible member 264 wound around a second pulley 266 keyed on a drive shaft of the second rotary motor 260; the second flexible member 264 is provided with a first end portion 268 rigidly connected to the first support member 241 for moving along a rectilinear path directed transversally to the rectilinear path of the bracket 220 with respect to the frame 10, and therefore with respect to the frame 101 of the forming machine 1.
With reference to figure 3, the first actuating device 24 comprises a second slide 2416 coupled to the first linear guide 2410 in a freely sliding manner and carrying a second bar 23 through a second bracket 221 rigidly coupled to the second transport branch 2422 of the first flexible member 242. Therefore, the two slides 2412 and 2416 move symmetrically (travelling equal and opposite spaces in equal times) and transversally to the direction D through the first flexible member 242.
With particular reference to figures 1 and 4, the folding unit 1 comprises a balancing device 40 comprising a linear actuator 41, whose armour 42 (figure 1) is rigidly connected to the frame 101 of the machine 100 and is arranged above the unit 1, in an intermediate position between the side portions 11 and 13 of the frame 10. The actuator 41 is provided with a stem 44 that is aligned with the direction D and has a free end 45 to which an arm 46 is hinged that is, in turn, keyed on the centre of a beam 47 with circular cross-section supported by the frame 101 in a rotating manner around an axis 102, parallel to the direction D through a pair of connecting rods 103 and 104, shown only in figure 4.
In view of the above description, the balancing device 40, and, more in particular, the actuator 41, supports the first rectilinear guide 2410, so as to prevent the unit 1 from vertically moving on a plane 12 for feeding the panels P crossing the folding station 110 and extending along the direction D.
It should be noted that at least one of the first rotary motor 244 and the second rotary motor 260 comprises a brushless motor and that the unit 1 comprises a control unit 50, to which the two rotary motors 244 and 260 are electronically connected. The choice of this kind of actuation system, and the combination thereof with the unit 50 allows, through a data processing device 52, usually a personal computer or a tablet, to manage, remotely and point-to-point, the movement of the first and of the second flexible members 242 and 264, therefore the position of the bars 22 and 23 in the directions transverse to the direction D and to modulate the movement thereof at will as regards speed and acceleration separately. The presence of the data processing device 52 allows to store the settings of the first and the second actuating devices 24 and 26. On the other hand, the balancing device 40 may be considered as a safety device, as it ensures that the bars 22 and 23 are always above the plane 12, without interfering with the feeding of the panels P.
The use of the folding unit 1 is clearly apparent from the description above and does not require further explanations. However, it should be specified that the choice of using brushless motors allows to manage, remotely and point-to-point, the movement of the first and of the second flexible members 242 and 264, through a computerized device thanks to the presence of the unit 50. Therefore, thanks to this electronic equipment, it is possible to modulate the movement of the bars 22 and 23 at will as regards speed and acceleration separately, in the directions transverse to the direction D in order to prepare the unit 1 for changing the format of the panels P without the need for accessing the same unit 1 and acting on the settings of the mechanical transport and transmission members.
On the other hand, the presence of the balancing device ensures that the bars 22 and 23 are always above the plane 12 without interfering with the feeding of the panels P also in the steps of regulating the kinematic and dynamic parameters controlling the operation of the first actuating device 24 and of the second actuating device 26.
In view of the above description, the folding unit 1 is suitable to form each of the three models of reinforced corners A, A' and A", according to pre-set trajectories T followed by the first and the second bars 22 and 23, managing in a combined manner the operation of the first and of the second actuating devices 24 and 26 and, substantially, the rectilinear movement of the first bracket 220 and of the first support member 241 through the activation of the first rotary motor 244 and the second rotary motor 260 according to what illustrated, both during the step of setting (of the folding unit 1) and during the production step.
Therefore, the unit 1 allows to provide a folding method for folding die-cut panels P through the use of the forming machine 100 wherein the method comprises a first step of feeding each panel P along the direction D; a second step of folding, in succession, a flap L of each panel P through the bar 22 along the curvilinear trajectory T. The second step comprises a third step of actuating a first rotary motor 244 of the first actuating device 24 to move the first bar 22 with rectilinear motion transversally to the direction D through a first transmission 240, comprising a first flexible member 242 mechanically coupled to the first rotary motor 244.
The method furthermore comprises a fourth step of actuating the second rotary motor 260 of the second actuating device 26 carried by the frame 10 and the second transmission 262 provided with the second flexible member 264 rotoidally coupled to the second rotary motor 260 through the second pulley 266.
It should be specified that the fact that the first actuating device 24 and the second actuating device 26 are independent of each other as regards mechanics and actuation allows to perform the second and the fourth steps in an independent way both during the change of the settings for the format change and during the execution of the folding steps for folding the flaps L of the panels P.
Moreover, the use of the data processing device 52 of the folding unit 1 allows to prepare the machine 100 for the format change of the panels P practically instantaneously, for instance taking, from a library of information corresponding to a plurality of different formats of panels P of the data processing device 52, a specific piece of information on the regulation of the first and of the second actuating devices 24 and 26, or significantly shortening the step of regulating the unit 1 for the new format, thanks to the possibility of performing the changes starting from a format similar in shape and/or dimensions.
Moreover, the fact that the actuating unit 20 is provided with actuating devices dedicated to move each bar 22/23 respectively along distinct directions and electronically controlled through the unit 50, together with the data processing device 52, allows to fold easily panels P of asymmetrical shape, i.e. having asymmetrical portions, in succession, in different times, by means of a single folding unit. This can be done by adapting to each folding step the setting of the actuating unit 20 and therefore of the first and the second actuating devices 24 and 26, through the unit 50 and the processing device 52. It is therefore possible to affirm that the unit 1 is a folding unit provided with a simplified mechanical equipment, that can be set differently in real time so as to treat differently distinct portions of the panels P to be folded, and, therefore, to produce trays V with reinforced corners A having different shapes (for instance, although without limitation, as in figure 7) for each panel P.
In view of the above description, each folding unit shaped similarly to the unit 1 allows to control the movement of the two bars 22 and 23 along optimized paths so that the folding of the flaps of each die-cut panel P can be easily adjusted and repeated, thus solving the drawbacks of the prior art and thus representing a new and original source of economic interest for the Applicant.

Claims

Folding unit (1) comprising a frame (10) that extends along a given direction (D) and supports a first folding bar (22) directed according to said given direction (D) through the interposition of an actuating unit (20); said actuating unit (20) comprising a first actuating device (24) and a second actuating device (26) carried by said frame (10) and associated with said first bar (22) to move this latter along a curvilinear trajectory (T) that is transverse to said given direction (D) in order to fold flaps (L) of a die-cut panel (P); wherein said first actuating device (24) and second actuating device (26) are provided each with a first transmission (240) and a second transmission (262), respectively, actuated by means of a first rotary motor (244) and a second rotary motor (260), respectively mechanically coupled to said first bar (22) to move it with a rectilinear motion; characterized in that said first transmission (240) comprises a first flexible member (242) mechanically coupled to said first rotary motor (244) through a first pulley (246), and in that said first actuating device (24) comprises a first support member (241), provided with rectilinear guiding means (2410) directed transversally to said given direction (D), and a first slide (2412), coupled to said rectilinear guiding means (2410) in a freely sliding manner; said first slide (2412) carrying said first bar (22) through a first bracket (220) coupled to said first flexible member (242) so as to be movable with respect to said first support member (241) through said first rotary motor (244).
Folding unit according to claim 1, characterized in that said first flexible member (242) is annular and has a first and a second transport branches (2421) (2422) parallel to said first rectilinear guiding means (2410); said first bracket (220) being rigidly coupled to said first transport branch (2421) of said first flexible member (242).
Folding unit according to any one of claims 1 to 2, characterized in that said first support member (241) has an elongated portion (2414) arranged transversally to said first rectilinear guide (2410) and coupled in a sliding manner transversally to said given direction (D) through a slide-guide device (30); said second device (26) being designed to move said elongated portion (2414) longitudinally with respect to said frame (10) transversally to said first device (24).
Folding unit according to claim 3, characterized in that said second device (26) comprises a second rotary motor (260) carried by said frame (10) and a second transmission (262) provided with a second flexible member (264) rotoidally coupled to said second rotary motor (260) through a second pulley (266) and provided with a first end portion (268) rigidly connected to said first support member (241) to move it with respect to said frame (10).
Folding unit according to any one of claims 2-4, characterized in that said first actuating device (24) comprises a second slide (2416) coupled to said linear guiding means (2410) in a freely sliding manner and carrying a second bar (23) through a second bracket (221) rigidly coupled to said second transport branch (2422) of said first flexible member (242).
Folding unit according to claim 5, characterized in that said elongated portion (2414) extends vertically; a balancing device (40) being arranged between said frame (10) and said first support member (241) to modulate the vertical movement of said first support member (241) in combination with said second rotary motor (260).
Folding unit according to any one of claims 4 to 6, characterized in that at least one of said first rotary motor (244) and second rotary motor (260) comprises a brushless motor.
Folding unit according to claim 7, characterized by comprising a control device (50) connected to each said first rotary motor (244) and second rotary motor (260) to modulate the rotation of the respective first and second pulleys (246) (266) differently; a data processing device (52) being provided to control, independently, said first rotary motor (244) and second rotary motor (260) in real time.
Forming machine (100) provided with a folding station to fold die cut panels (P); characterized in that said folding station (110) comprises a folding unit (1) according to one of claims 1 to 8.
Method for folding die cut panels (P) by means of a forming machine according to claim 9; said method comprising a first step of feeding each said panel (P) along said given direction (D); a second step of folding, in succession, a said flap (L) of each said panel (P) through said first bar along said curvilinear trajectory (T); characterized in that said first step comprises a third step of actuating said first rotary motor (244) of said first actuating device (24) to move said first bar (22) with rectilinear motion transversally to said given direction (D) through said first transmission (240) comprising a first flexible member (242) mechanically coupled to said first rotary motor (244), and by comprising a fourth step of actuating said second rotary motor (260) of said second actuating device (26) carried by said frame (10) and said second transmission (262) provided with a second flexible member (264) rotoidally coupled to said second rotary motor (260) through a second pulley (266).
Method according to claim 10, characterized in that said second and fourth steps can be performed contemporaneously or not, at will.