EP1419969A1

EP1419969A1 - A device and method for picking up and erecting carton blanks

Info

Publication number: EP1419969A1
Application number: EP02425698A
Authority: EP
Inventors: Giuseppino Naldi
Original assignee: Romaco SRL
Current assignee: Romaco SRL
Priority date: 2002-11-15
Filing date: 2002-11-15
Publication date: 2004-05-19
Anticipated expiration: 2022-11-15
Also published as: DE60204469T2; EP1419969B1; DE60204469D1; ATE296757T1

Abstract

The device (7) for picking up and erecting carton blanks (2) in a line (1) for packing products in containers made from flat blanks (2) comprises an arm (11) that swings about an axis (A1), the swing arm (11) mounting a first and a second suction cup (15, 20). Each of the suction cups (15, 20) engages with one of the two substantially planar, parallel and opposite faces (5, 6) of a flat blank (2) in such a way as to erect the blank (2).

Description

The present invention relates to a device and method for picking up and erecting carton blanks.
In particular, but without restricting the scope of the inventive concept, the invention refers to a device and a method for picking up flat carton blanks made of cardboard or stiff paper, erecting them to a tubular shape and placing them on a conveyor forming part of a packaging line.
In the packaging sector, many types of products are packed in containers consisting of tubular blanks made from specially shaped flat sheets of cardboard or stiff paper. The flat shape of the blanks enables large quantities of the containers to be stored in a small space prior to use, but means that the blanks must be erected, that is to say, opened out into tubular form before the products are inserted into them.
There are many prior art devices for erecting flat blanks. These comprise suction pickup means, such as suction cups or similar means, which extract the blanks one by one from a feed magazine where the blanks are stacked flat, and contact elements designed to erect each blank by moving relative to the blank itself. These devices also place the substantially erect blank on a conveyor, normally a conveyor belt, which transfers it to the next station on the packaging line where the container is given its final shape and filled with products.
These prior art devices have several disadvantages. One disadvantage is due to the complex linkage and large number of actuators necessary to perform all the movements to pick up, erect and then release the carton.
Another disadvantage of prior art devices is that the contact elements may damage the surface of the blank during erection. Especially when handling the blanks of containers with a square cross section, whose side panels are all substantially the same size, the erection of the blanks using contact elements may present problems, sometimes leading to an unwanted extra fold being made in the blank.
Yet another disadvantage of prior art devices is the difficulty of changing over to blanks of different sizes, mainly on account of the contact elements.
The aim of the present invention is to overcome the above mentioned disadvantages.
The invention accordingly provides a device as described in claim 1, for picking up and erecting carton blanks.
Another aim of the present invention is to provide a method for picking up and erecting carton blanks, that is functional, practical and easy to implement.
The invention accordingly provides a method as described in claim 12, for picking up and erecting carton blanks.
The technical characteristics of the invention, with reference to the above aims, are clearly described in the claims below and its advantages are apparent from the detailed description which follows, with reference to the accompanying drawings which illustrate a preferred embodiment of the invention provided merely by way of example without restricting the scope of the inventive concept, and in which:

Figure 1 is a perspective view from above of a device for picking up and erecting carton blanks according to the present invention;
Figures 2 to 5 are schematic side elevation views, with some parts cut away in order to better illustrate others, of a succession of steps in the working cycle of the device of Figure 1;
Figure 6 is a schematic plan view, with some parts cut away and others in cross section, of the device of Figure 1.

With reference to the accompanying drawings, the numeral 1 denotes in its entirety a part of a line for packing products into containers (not illustrated) made from blanks 2. More specifically, but without restricting the scope of the invention, the blanks 2 are made of cardboard or stiff paper.
As shown in Figure 1, the line 1 comprises a feed station 3 where the blanks 2 are stacked flat in a magazine 4. The magazine 4 is of the known type and therefore not described in detail.
The flat blanks 2 present a lower first face 5 and an upper second face 6, which are substantially planar, parallel and opposite to each other, each of the faces 5, 6 having two main panels 5a, 5b, 6a, 6b, respectively, which will form the side walls of the finished container.
The line 1 comprises a device 7 for picking up and erecting the blanks 2, the device being designed to extract the blanks 2 from the magazine 4, to erect them into a tubular shape and to transfer them, at a transfer station 8, to respective pickup elements 9 of a conveyor belt 10, which is of known type and therefore not described in detail.
The pickup and erection device 7 comprises a swing arm 11 keyed at one end of it 11a to a first shaft 12 having a respective axis A1.
The first shaft 12 is fitted inside a hole 13 in the centre of a first disc 14 that is coaxial with the first shaft 12 itself, the first disc 14 being fixed relative to the axis A1.
At a second end 11b of it, longitudinally opposite the first end 11a, the arm 11 comprises a first suction cup 15 mounted on a block 16 attached to the arm 11.
Close to the second end 11b, the arm 11 also mounts a mobile member 17 which is slidably engaged between two idle rollers, labelled 18 and 19, which are pivoted on respective pins 18a and 19a attached to the arm 11. The mobile member 17 has the shape of a crown wheel sector whose teeth 22 extend along a perimetric portion of it 17a.
The mobile member 17 engages with the rollers 18, 19 in such a way as to swing about a second axis of rotation A2, parallel to the first axis of rotation A1, positioned on the outside of the arm 11 at the centre of the crown wheel of which the mobile member 17 constitutes a sector.
At a second end 17b of the mobile member 17, there is a second suction cup 20 mounted on a block 21 attached to the member 17.
The pickup and erection device 7 further comprises a toothed wheel 23 mounted on the arm 11 and pivoted on a third axis A3 parallel to the first axis A1. The wheel 23 is designed to mesh with the teeth 22 of the mobile member 17.
Part of a peripheral surface 14a of the first disc 14 has looped around it a toothed belt 24 whose toothed inside face is in contact with the peripheral surface 14a itself. The toothed belt 24 is attached to the first disc 14 by a fixing element 25.
The toothed belt 24 is looped around the first disc 14 and around a pulley 26 that is keyed to a second shaft 27 mounted on the arm 11 and rotatable about a fourth axis A4 parallel to the first axis A1.
Close to the pulley 26, the arm 11 mounts two idle rollers 26a, 26b which press the toothed belt 24 inwards so that the toothed belt 24 is held well against the pulley 26.
The second shaft 27 has a second disc 28 keyed to it longitudinally opposite the pulley 26 and coaxial with the latter.
A first link 29 is eccentrically pivoted to the second disc 28 by a first end of it 29a.
At a second end of it 29b, longitudinally opposite the first end 29a, the first link 29 is eccentrically pivoted to the toothed wheel 23.
The second disc 28 and the first link 29 together form a crank mechanism 30 where the second disc 28 constitutes the crank.
With reference to Figure 2, the line 1 also comprises a device 31 for driving the pickup and erection device 7. The device 31 comprises a four-point linkage 32 defined by an upper arm 33, a lower arm 34 and a second link 35 connecting the two arms.
The upper arm 33 and the lower arm 34 are connected by their ends 33a, 34a, respectively, to the first shaft 12, to which the arm 11 is keyed, and to a third shaft 36 that is parallel to the shaft 12 and positioned below it.
The third shaft 36 is also rigidly connected to a drive rod 37. Through the third shaft 36, the rod 37 transmits to the four-point linkage 32 a reciprocating drive motion provided through a rod-like element 38 by a motor which is neither illustrated or described since it is well within the knowledge of one of ordinary skill in the art.
The first suction cup 15 and the related block 16 mounted on the arm 11 constitutes, for the pickup and erection device 7, first suction means 40 for holding the carton blank 2.
The second suction cup 20 and the related block 21 mounted on the mobile member 17 constitutes, for the pickup and erection device 7, second suction means 41 for holding the carton blank 2.
The suction cups 15, 20 are connected by respective conduits 42 to a vacuum source represented symbolically as a block 43 in Figure 1.
The aforementioned conveyor belt 10 and the respective pickup elements 9 constitute, for the packing line 1, means 44 for transferring the carton blanks 2 after they have been erected to tubular form.
During use, as illustrated in Figures 2 and 5, the drive device 31 causes the swing arm 11 to turn alternately in both directions about the axis A1, between a first end position, where it picks up a carton blank 2 from the feed station 3, and a second end position, where it releases the blank 2 onto the transfer station 8.
with reference to Figures 1, 2 and 6, the first disc 14, the toothed belt 24, the pulley 26, the second disc 28, the first link 29, the toothed wheel 23 and the mobile member 17 together constitute a kinematic chain which, when the arm 11 swings about the axis A1, causes the simultaneous swinging of the mobile member 17 according to a defined transmission ratio.
In other words, an angular movement of the swing arm 11 about its axis A1 is transmitted by the toothed belt 24 to the pulley 26 which rotates and thus causes the second disc 28 attached to it to rotate about the axis A4. The first link 29, actuated by the second disc 28, transmits a swinging motion to the toothed wheel 23 which meshes with the mobile member 17 and thus causes it to slide on the idle rollers 18, 19 according to a swinging motion about the second axis A2.
At the aforementioned first end position of the arm 11 illustrated in Figure 2, the first suction cup 15, which is fixed to the arm 11, moves into contact with the lower face 5 of the carton blank 2 and, following activation of the vacuum source 43 by a control unit that is not illustrated, grips the main panel 5a of the carton blank 2.
Figure 3 illustrates a first intermediate position of the arm 11 between the aforementioned first and second end positions. At this first intermediate position of the swing arm 11, the suction cups 15, 20 are as close together as possible and the second cup 20 is in contact with the upper face 6 of the carton blank 2, which is still flat. More specifically, the second cup 20 grips the main panel 6a adjacent to the panel 5a of the lower face 5 and connected to the latter by a crease 39.
Figure 4 illustrates a second intermediate position of the arm 11 between the aforementioned first and second end positions. At this second intermediate position of the swing arm 11, the suction cups 15 and 20, which are both gripping the respective main panels 5a, 6a, have started moving away from each other, thus causing the panels 5a, 6a to rotate about the crease 39. This movement of the suction cups 15, 20 is achieved by the sliding of the mobile member 17 on the idle rollers 18, 19 as a result of the clockwise rotation, indicated by the arrow F1 in the drawings, of the toothed wheel 23 that meshes with the mobile member 17 itself.
As illustrated in Figure 5 and as mentioned above, when the swing arm 11 reaches its second end position, it releases the carton blank 2, which is now erect in a fully open, tubular configuration, and transfers it to the conveyor belt 10 between two gripping elements 9 on the conveyor belt 10 itself.
During the passage from the second intermediate position illustrated in Figure 4 to the second end position illustrated in Figure 5, the sliding of the mobile member 17 completely erects the carton blank 2, which, once inserted into the space between the two gripping elements 9, reaches the fully open, tubular configuration, with each of the main panels 5a, 5b, 6a, 6b at right angles to the adjacent one. As soon as the carton blank 2 reaches its final, tubular, erect configuration the above mentioned control unit, which is not illustrated, deactivates the fluid connection between the second suction cup 20 and the vacuum source 43.
Next, when the carton blank 2 is securely held between the gripping elements 9 of the conveyor 10, the fluid connection between the first suction cup 15 and the vacuum source 43 is also deactivated.
The drive device 31 then rotates the swing arm 11 back in an anticlockwise direction, indicated by the arrow F2 in Figure 5, to the first pickup position, illustrated in Figure 2, and another cycle in which the next carton blank 2 is extracted, erected and released is started.
The present invention therefore advantageously achieves the aim of providing a compact device for picking up and erecting the carton blanks 2.
Advantageously, the pickup and erection device 7 according to the present invention does not require any adjustments to erect carton blanks 2 of many different sizes, since it acts on two adjacent main panels 5a, 6a of the carton blank 2 and erects the carton through a positive action.
Advantageously, the action by which the carton blanks 2 are erected by the device 7 according to the invention is positive and no contact elements need to be used.
It will be understood that the invention can be subject to modifications and variations without thereby departing from the scope of the inventive concept. Moreover, all the details of the invention may be substituted by technically equivalent elements.

Claims

A device for picking up and erecting carton blanks (2), in a line (1) for packing products in containers made from these flat blanks (2), comprising a swing arm (11) that pivots about a first axis of rotation (A1) and is mobile, relative to the first axis (A1), at least between a first end position, where it picks up a carton blank (2) from a feed station (3), in which the carton blanks (2) are stacked flat and present two substantially planar, parallel and opposite faces (5, 6), each of the faces (5, 6) having at least two main panels (5a, 5b, 6a, 6b), which will form the side walls of a finished container, and a second end position, where it releases the blank (2), after erecting it to a tubular configuration, and transfers it to corresponding transfer means (44), the device being characterised in that the swing arm (11) comprises and mounts first and second suction means (40, 41), the first and second suction means (40, 41) engaging with the flat carton blank (2) at each of its two opposite faces (5, 6), respectively.
The device according to claim 1, characterised in that the first and second suction means (40, 41) engage with and hold the carton blank by two of its main panels (5a, 6a), the panels (5a, 6a) being adjacent to each other and connected by a crease (39) made in the carton blank (2) itself, the crease (39) being substantially parallel to the axis of rotation (A1) of the swing arm (11).
The device according to claim 1 or 2, characterised in that, between the first end position of gripping and the second end position of releasing the carton blanks (2), the first and second suction means (40, 41) move relative to each other according to a swinging motion about a second axis of rotation (A2) parallel to the first axis of rotation (A1) of the swing arm (11).
The device according to claim 3, characterised in that the second axis of rotation (A2) substantially coincides with the crease (39) between the adjacent main panels (5a, 6a) of the carton blank (2).
The device according to any of the foregoing claims from 1 to 4, characterised in that the first suction means (40) are attached to the swing arm (11) and the second suction means (41) comprise a mobile member (17) that slides relative to the swing arm (11).
The device according to claim 5, characterised in that the mobile member (17) has the shape of a crown wheel sector whose teeth (22) extend along a perimetric portion of it (17a).
The device according to claim 6, characterised in that the swing arm (11) comprises a toothed wheel (23) pivoted on a third axis (A3) parallel to the first axis (A1) and designed to mesh with the teeth (22) of the mobile member (17).
The device according to claim 7, characterised in that the toothed wheel (23) is driven by a crank mechanism (30), the crank (28) being designed to swing about a fourth axis (A4).
The device according to claim 8, characterised in that the crank (28) is driven by a toothed belt (24) looped at least partly around a disc (14) that is coaxial with the first axis (A1) and fixed relative to it.
The device according to claim 1, characterised in that each of the first and second suction means (40, 41) comprises a suction cup (15, 20) that is fluidly connected to a vacuum source (43).
A method for picking up and erecting carton blanks (2) comprising the following steps:

picking up the carton blanks (2) from a feed station (3), in which the blanks are stacked flat and each presents two substantially planar, parallel and opposite faces (5, 6), each of the faces (5, 6) having at least two main panels (5a, 5b, 6a, 6b), which will form the side walls of a finished container;

erecting the carton blanks (2) to a fully open, tubular configuration;

transferring the carton blanks (2) from the feed station (3) to a transfer station (8);

releasing the carton blanks (2), after erecting them to a tubular configuration, so as to transfer them to corresponding transfer means (44);

the method being characterised in that the step of erecting the carton blanks (2) comprises the further steps of:

using the first suction means (40) to grip a first main panel (5a) of one of the faces (5, 6);

using the second suction means (41) to grip a second main panel (6a) of the other of the faces (5, 6), the second main panel (6a) being adjacent to the first main panel (5a).
The method according to claim 11, characterised in that the step of erecting the carton blanks (2) comprises the further step of:

moving the first and second suction means (40, 41) relative to each other according to a substantially swinging motion.
The method according to claim 12, characterised in that the step of moving the first and second suction means (40, 41) relative to each other is performed by swinging the first or the second suction means (40, 41) about an axis (A2) that substantially coincides with a crease (39) made between the two adjacent main panels (5a, 6a) of the carton blank (2).
The method according to any of the foregoing claims from 11 to 13, characterised in that the steps of erecting the carton blanks (2) and of transferring them from the feed station (3) to the transfer station (8) are performed by mechanically driving the suction means (40, 41) using a single motor.