A labeling device for automatic net-packing machines

Abstract: The invention related to a labeling device for automatic net-packing machines comprising a net-packing station (27) for each container (7), supported by a car (18), on which car (18) a clipping and cutting group is fixed. The labeling device (4) is of a type equipped with a synchronising apparatus (8) for synchronising the labeling device (4) with the clipping and cutting group (6) and comprising at least one printing and feeding machine (1), and further comprises a mobile gripping mechanism (3) to grip at least one label (2) at a time from the printing and feeding machine (1) and take the label (2) to a clipping point, keeping it in a same position during transport.

Description: The invention relates to a labeling device for automatic net-packing machines. Over a period of years and in various stages, machines for packing containers of fruit and vegetable products have become more and more automatised. In 1983 a completely automatic machine was realised by the present applicant which was able to net-pack the containers of fruit and vegetable products and apply support and labeling strips on them. The machine in question, Italian Patent no. 1,168,656, and European Patent application EP-A-0 123 655, obtains its aim by placing several stations in a line: in particular, the machine comprises a container feeding station, with the containers transiting inside a net-bearing tube and being brought to a net-packing station for each container, whereat there is also a support-strip-application and labeling station, all operating in phase. In this way, the production rate was considerably increased, and the presence of operators almost completely obviated. In the intervening years various improvements have been made to single stations in the line, with the aim of further improving the machine's performance, improvements which have been protected by various patents. At present, machines of this kind apply only string-attached labels. To obtain other kinds of label, for example flag-type labels, up until now feeding devices bringing one end of the label directly to the clipping point have been used. Since, obviously, the latter activity cannot be performed at the same time as the clipping, and since between the printing of one label and the next there is a time-lapse which is longer than the machine cycle time, the production rhythm is determined by the printing time of the labels, penalising the packing production speed. Further, the machines supply the labels from below, where during operation considerable dirt collects, and what is more, the labels end up on the bottom of the containers and are less apparent to consumers. The aim of the invention is to eliminate the above-mentioned drawbacks. The invention, as it is characterised in the claims that follow, solves the problem by freeing the machine cycle from the no-string-attached label-printing device. One of the advantages obtained by the present invention consists in the fact that the no-string-attached label feeding and printing machine is removed to a cleaner zone, that is, a higher zone than the main functioning line of the automatic net-packing machine. A further important advantage is that the pause times of the no-string-attached label printing and feeding machine are drastically reduced, since the time necessary for the printing of one label is also exploited for the application of the preceding label: this leads to a relevant increase in the number of containers produced per time unit. A further advantage in favour of the present invention is that by positioning the no-string-attached label printer above, the meaningful part of the label is clearly in view to the consumer. Further characteristics and advantages of the present invention will better emerge from the detailed description that follows, of a preferred but non-exclusive embodiment here illustrated in the form of a non-limiting example in the accompanying drawings, in which: figure 1 shows the machine applying the invention in its entirety in perspective view; figure 2 shows the invention in perspective view; figures 3, 4 and 5 shows the invention respectively in a frontal view and in two sectioned lateral views of details evidencing some applicational characteristics. As can be seen in the figures, the invention concerns a labeling device for automatic net-packing machines. The device is particularly suitable for machines of this type comprising a net-packing station 17 of each container 7, supported by a carriage 18 bearing a clipping and cutting group 6. The labeling device 4 is of the type equipped with a synchronising apparatus 8 with the clipping and cutting group 6 and comprises at least one no-string-attached label printing and feeding machine 1; it also has a mobile gripping mechanism 3 to take at least one no-string-attached label 2 at a time from the said label printing and feeding machine 1 and to transport it to the clipping point, keeping it in the same position during the transport. In this way, the no-string-attached label printing and feeding machine 1 does not have significant dead times, as the time necessary for printing a new label 2 corresponds to that required by the mobile gripping mechanism 3 to transport the preceding label 2 to the clipping point and to return to the label 2 feeding point. At the feeding moment, the no-string-attached labels 2 are curved as they have been peeled off a roll of like labels 2, so first stabilising means 9 of the label position are provided, synchronised with the movement of the mobile gripping mechanism 3 and aimed at guaranteeing a correct gripping of the label 2 from the said label printing and feeding machine 1. The clipping phase is also a very delicate moment. Just as in previous machines, the operation takes place on a horizontal plane, and the label 2 must also be absolutely horizontal. Second stabilising means 12 of the label position are provided for this reason, synchronised with the movement of the mobile gripping mechanism 3 and aimed at permitting a closing of the net and at least the application of the label 2 with one single clipping operation. In the embodiment shown, the first and the second stabilising means 9 and 12 comprise respectively a first blowing element 10 acting on the no-string-attached label 2 during the ascending run of the mobile gripping mechanism 3 so as to predispose the end tract of the label 2 vertically, and a second blowing element 13 solid to the mobile gripping mechanism 3 and acting on the label 2 during the clipping phase so as to keep the end tract of the label 2 in a substantially horizontal lie. Other embodiments are, however, possible: for example, the first stabilising means 9 might comprise a mechanical guide 11 for the label 2, represented by a broken line in figure 5, synchronised with the mobile gripping mechanism 3 in such a way as to pass from a first advanced position, in which the end tract of the label 2 is kept in a vertical position, up until the interaction of the label 2 with the mobile gripping mechanism 3, to a second, retracted position in order to avoid interference with the mobile gripping mechanism 3, which is rising, and to follow the appearance of the next label 2. The embodiment described herein relates to the case in which a guillotine 19 is stationed on the carriage 18, which guillotine 19 comprises a first pair of fixed V-conformed elements 20, arranged identically transversely to the advancement direction of the containers 7 and distanced parallel to them so as to receive, inferiorly and at the vertex of the V, a clipping and cutting head 6a which is part of the group 6; a second pair of mobile elements 21, conformed in an identical upturned V shape, and cooperating with the first elements 20 but located above them and slightly out of alignment with respect to them. The second elements 21 are slidably supported by at least one pair of columns 23, solid to the carriage 18 and vertically translating in two directions from a first, raised position, wherein the two pairs of elements 20 and 21 create a rhomboidal opening 22 through which the container 7 can transit, to a second, lowered position, in which the two pairs of elements 20 and 21 grip the strip of net which is acted upon by the clipping and cutting head 6a. In this case, the mobile gripping mechanism 3 is solid to the second pair of mobile elements 21, the first stabilising means 9 of the label 2 position being solid to the label printing and feeding machine 1 and the second stabilising means 12 being solid to the same second pair of mobile elements 21. The mobile gripping mechanism 3 comprises: pliers 14 constituted by a curved appendix 15 fixed to an element 21a of the second pair of mobile elements 21 and to a contrast element 16 solid to the same element 21a, the appendix 15 being free to rotate with respect to the contrast element 16; a pneumatic piston 17 for controlling the movement of the appendix 15 acting at a superior level to the level of the horizontal rotation axis 5 of the appendix 15; a recall spring 25 of the curved appendix 15, visible in figure 3, representing a detail in frontal view, aimed at leaving the pliers 14 open when the pneumatic piston 17 is not activated. The synchronising apparatus 8 to regulate the functioning of the pneumatic piston 17, the label printing and feeding machine 1, the mobile gripping mechanism 3, the clipping and cutting group 6 and the first and second stabilising means 9 and 12, comprises electrical devices 30a and 30b which signal when the lower and upper dead points have been reached in the run of the mobile gripping mechanism 3. The device functioning can be schematised as follows. During the rising of the second pair of mobile elements 21, to which the mobile gripping mechanism 3 is solid, the pneumatic pistol 17 is released, while the first blowing element 10 keeps the label 2 disposed vertically so that it can be correctly met and subsequently gripped between the curved appendix 15 and the contrast element 16. When the second pair of mobile elements 21 reaches the upper dead point a first electrical device 30a is activated, which commands the cutting of the label 2 by the label printing and feeding machine 1, the end of the action of the first blowing element 10 and the contemporaneous beginning of the action of the pneumatic piston 17 which, acting on the curved appendix 15, determines the gripping of the pliers 14, previously open, due to the presence of the recall spring 25 associated to the curved appendix 15 itself. During the lowering, the pneumatic piston 17 continues to act, keeping the pliers closed. Similarly to the above, a second electrical device 30b is activated when the second pair of mobile elements 21 reaches the lower dead point. In sequential order, the following are activated: the second blowing element 13, which keeps the free end of the label 2 horizontal, resisting its tendency to curl back on itself and permitting of realising an optimal clipping, the clipping operation, the deactivating of the second blowing element 13 and the arresting of the pneumatic piston 17 action on the curved appendix 15. Once all this is achieved, a new cycle begins with the rising of the second mobile elements 21.

Claims: A labelling device for automatic net-packing machines of the type comprising: a net-packing station (27) for containers (7), supported by a carriage (18); a clipping and cutting group (6) being fixed on the carriage (18); a device (19) also fixed on said carriage (18) comprising means movable between a first retracted position and a second position for cooperating with said group (6) for holding back the strip of net acted upon by the clipping and cutting head (6a); a synchronising apparatus (8) to synchronise the labelling device with the clipping and cutting group (6); at least a label printing and feeding machine (1); characterised in that: the movable means of the device (19) comprise a mobile gripping mechanism (3) arranged to receive at least a no string label (2) from said label printing and feeding machine (1), arranged at said first retracted position, and to transport it to the second position for attachement to the net, keeping it in the same attitude during transport from the first to the second position. A labeling device as in claim 1, characterised in that a first stabilising means (9) of a position of the label (2) are provided, synchronised to a movement of the mobile gripping mechanism (3), to allow the mobile gripping mechanism (3) correctly to receive the label (2) from the label printing and feeding machine (1). A labeling device as in claim 1, characterised in that a second stabilising means (12) of the label (2) position are provided, synchronised with a movement of the mobile gripping mechanism (3) and aimed at permitting of closing a net and at least applying the label (2) with a single clipping operation. A labeling device as in claim 1, of a type wherein a guillotine device (19) is also fixed on the said carriage (18), which guillotine (19) comprises a first pair of fixed V-conformed elements (20), arranged identically transversely to the advancement direction of the containers (7) and distanced parallel to them so as to receive, inferiorly and at the vertex of the V, a clipping and cutting head (6a) which is part of the group (6); a second pair of mobile elements (21), conformed in an identical upturned V shape, and cooperating with the first elements (20) but located above them and slightly out of alignment with respect to them which second elements 21 are slidably supported by at least one pair of columns (23), solid to the carriage (18) and vertically translating in two directions from a first, raised position, wherein the two pairs of elements (20) and (21) identify a rhomboidal opening (22) in which the container (7) can transit, to a second, lowered position, in which the two pairs of elements (20 and 21) hold back the strip of net acted upon by the clipping and cutting head (6a), the labeling device (4) being characterised in that the mobile gripping mechanism (3) is solid to the second pair of mobile elements (21), a first stabilising means (9) being solid to the no-string-attached label printing and feeding machine (1) and a second stabilising means (12) being solid to the second pair of mobile elements (21), the mobile gripping mechanism (3) comprising: pliers (14) constituted by a curved appendix (15) fixed to an element (21a) of the second pair of mobile elements (21) and to a contrast element (16) solid to the same element (21a), the appendix (15) being free to rotate with respect to the contrast element (16); a pneumatic piston (17) for controlling movement of the appendix (15) acting at a superior level to a level of a horizontal rotation axis (5) of the appendix (15); a recall spring (25) of the curved appendix (15), aimed at leaving the pliers (14) open when the pneumatic piston (17) is not activated. A labeling device as in claim 2, characterised in that the first stabilising means (9) comprise a first blowing element (10), acting on the label (2) during an ascendent run of the mobile gripping mechanism (3), in such a way as to dispose an end tract of the label (2) vertically. A labeling device as in claim 2, characterised in that the first stabilising means (9) comprise a mechanical guide (11) of the label (2), synchronised to the mobile gripping mechanism (3) in such a way as to pass from a first advanced position wherein the mechanical guide 11 keeps the end tract of the label (2) vertical up until an interaction of the end tract with the mobile gripping mechanism (3), to a second retracted position to avoid interference with the mobile gripping mechanism (3) which is rising, and to follow the appearance of a successive label (2). A labeling device as in claim 3, characterised in that the second stabilising means (12) comprise a second blowing element (13), solid to the mobile gripping mechanism (3) and acting on the label (2) during a descendent run of the mobile gripping mechanism (3), in such a way as to keep the end tract of the label (2) in a horizontal position. A labeling device as in claim 4, characterised in that it provides a synchronising apparatus (8) to regulate functioning of the pneumatic piston (17), the label printing and feeding machine (1), the mobile gripping mechanism (3), the clipping and cutting group (6), and the first and second stabilising means (9 and 12). A labeling device as in claim 8, characterised in that the synchronising apparatus (8) comprises a plurality of electronic devices (30) to signal when an upper and a lower dead points have been reached in the mobile gripping mechanism (3) run.

Inventors: BOLOGNESI BRUNO, BOLOGNESI, BRUNO
Applicants: SORMA SRL, SORMA S.R.L.
Application year: 1993
Main classification: B65C7
IPC codes: B65C7, B65B51