CUTTING DRUM FOR A LABELING MACHINE

Abstract

A cutting drum for a labeling machine, comprising a main drum body (2) that can be rotated about its own axis (2a) and is designed to receive in adhesion on its own lateral surface a label tape (120) on which multiple labels are printed in succession, along the perimeter of the main drum body (2), wherein there is at least one cutting device (4) comprising a respective suction chamber (5) that is open to the outer lateral surface of the drum and houses at least one blade (6), wherein the suction chamber (5) can be connected to air suction means (7) to draw the label tape (120) into an interior of the suction chamber (5) and against said blade (6) to produce the cutting of the label tape (120),wherein the cutting device (4) comprises a respective box-like body (8) for supporting the blade (6) which internally forms the suction chamber (5) and is detachably supported by said main drum body (2), wherein said blade (6) is coupled to the box-like body (8) by means of detachable retaining means.

Description

CUTTING DRUM FOR A LABELING MACHINE DESCRIPTIVE MEMORANDUM The present invention relates to a cutting drum for a labeling machine. As is known, labeling machines are used that allow the application of labels to containers obtained by cutting a continuous tape of labels that are wound on a reel or may be provided with portions of glue on the face of the labels designed to come into contact with the containers or may not have glue and, in this case, the machine is equipped with an assembly adapted to apply the glue to the labels. Labeling machines typically have a conveyor belt for the containers, usually consisting of a rotating carousel peripherally equipped with plates to hold the individual containers, which allow the containers to be rotated around the corresponding axes. At least one labeling unit is arranged along the perimeter of the carousel and normally has an unwinding assembly that is designed to unwind the label tape from its reel and feed it to a cutting drum that is provided with suction ports on its side surface to ensure retention of the label tape in adhesion to the side surface of the cutting drum and is provided with blades, which are fixed to the drum and operate in cooperation with a fixed contrast blade, to cut the label tape in the region between two consecutive labels. The labels separated after cutting are then released by the cutting drum to a transfer drum, which attaches them to the respective container arriving on the carousel. The cutting drum described above has the disadvantage of requiring precise adjustment of the position of the blades that are fixed to the cutting drum and the fixed blade to ensure the correct execution of the label cutting. Labeling machines are also known in which the cutting drum is provided with blades that are moved by means of respective drive cylinders, to allow the cutting of the label tape without requiring the presence of the fixed contrast blade. This type of solution, although valid, has a certain complexity in its construction. To overcome this and other drawbacks of the prior art, a cutting drum has been proposed, described in U.S. Patent US10343808 in the name of this same applicant, which is designed to receive, on its lateral surface, the label tape fed by the unwinding assembly and is provided, around its lateral surface, with a plurality of cutting devices, each of which comprises a blade that is integrally fixed to the cutting drum and accommodated in a respective suction chamber, which is formed in the cutting drum and opens into the lateral surface of said cutting drum. The suction chamber of each cutting device can be connected to air suction means, which allow the label tape to be pulled towards the inside of the suction chamber, to push it against the blade, thus cutting it. Although the cutting drum described above does not require precise adjustment of the blade position to cut the label tape correctly, and although it is quite simple to provide, in terms of its construction, it brings with it laborious operations to remove the worn blades and replace them with new ones. The objective of the present invention is to provide a cutting drum for a labeling machine that is capable of improving the prior art in one or more of the aforementioned aspects. To this end, it is an objective of the invention to provide a cutting drum that allows the replacement of worn blades to be carried out in a very simple and practical manner. Another objective of the invention is to provide a cutting drum for a labeling machine that is simple to provide, in terms of its construction. Another objective of the present invention is to provide a cutting drum for a labeling machine, which is capable of offering the broadest guarantees of reliability and safety in its operation. An additional objective of the present invention is to overcome the disadvantages of the prior art in an alternative manner to any existing solution. It is a no less important objective of the invention to provide a cutting drum that is also competitive from a purely economic point of view. This objective and this and other objectives, which will become more apparent from here on, are achieved by means of a cutting drum for a labeling machine in accordance with claim 1, optionally provided with one or more of the features of the dependent claims. Other features and advantages of the present invention will become more apparent from the description of some preferred, but not exclusive, embodiments of the cutting drum for a labeling machine according to the invention, which are illustrated by way of non-limiting example in the accompanying drawings, in which: Figure 1 is a perspective view of a cutting drum according to the invention; Figure 2 is a perspective view of the cutting drum according to the invention with an extended cutting device; Figure 3 is an exploded perspective view of a cutting device extracted from the cutting drum in accordance with a first embodiment; Figure 4 is a schematic top plan view of an accommodating seat formed in the cutting drum to accommodate a cutting device; Figure 5 is a perspective view of a second embodiment of the cutting drum device according to the invention; Figure 6 is an exploded front view of the cutting device in Figure 5; Figure 7 is a cross-sectional view, taken along plane VII-VII of Figure 6; Figure 8 is an exploded perspective view of the modality in Figure 5; Figure 9 is a perspective view of a third embodiment of the cutting drum device according to the invention; Figure 10 is a rear view of the cutting device of Figure 9; Figure 11 is a slightly exploded front view of the cutting device in Figure 9; Figure 12 is a cross-sectional view, taken along plane XII-XII of figure ii; Figure 13 is an exploded perspective view of the modality in Figure 9; Figure 14 is a perspective view of a fourth embodiment of the cutting drum device according to the invention; Figure 15 is a schematic top plan view of the accommodating seat formed in the cutting drum to accommodate the cutting device of Figure 14; Figure 16 is a front view of the cutting device of Figure 14; Figure 17 is a cross-sectional view, taken along plane XVII-XVII of Figure 16; Figure 18 is an exploded perspective view of the cutting device in Figure 14; Figure 19 is a schematic diametral sectional view of a portion of the cutting drum according to the invention; Figure 20 is a top plan view of the application of the cutting drum according to the invention to a labeling machine. Referring to the figures, the cutting drum for labeling machines according to the invention, generally designated by reference number 1, comprises a main drum body 2, which is substantially cylindrical, rotatably driven about its own axis 2a, and designed to receive adhesively on its own lateral surface a label tape 120, on which multiple labels are printed in succession and which can be fed to the main drum body 2 by means of an unwinding assembly 130, which is provided, for example, with a pair of traction rollers 130a and 130b, which pick up the roller tape 120 from a reel. In particular, suction ports 3 are provided on the side surface of the main drum body 2 in a known manner and are allowed to retain the label tape 120, as well as the labels separated after cutting, on said side surface of the main drum body 2. Along the perimeter of the main drum body 2 there is at least one cutting device 4, comprising a respective suction chamber 5, which is open on a lateral surface of the drum and in which at least one blade 6 is accommodated, conveniently arranged substantially along the diametral plane of the main drum body 2. The suction chamber 5 can be connected to air media 7, so that the label strip 120 can be pulled into the suction chamber 5 and against the blade 6 to produce the cutting of the label strip 120 in the separation region between two consecutive labels. It should be mentioned that multiple cutting devices 4 may also be provided, which are arranged along the peripheral region of the main drum body 2 and are spaced at a mutual circumferential distance that is at least equal to the length of the labels. According to the invention, the cutting device 4 comprises a respective box-like body 8 to support the blade 6, which internally forms the suction chamber 5. Also in accordance with the invention, the box-like body 8 is detachably supported by the main drum body 2, so that it can be removed from the main drum body 2 in case of maintenance or if it is necessary to remove the blade 6. What is more, the blade 6 is, in turn, attached to the body as a box 8 by means of removable retaining means, so that it can be detached from the body as a box 8 in order to be replaced with a new blade 6 if it is damaged or worn out. Advantageously, the box-like body 8 can be coupled or uncoupled with respect to the main drum body 2 by means of a relative sliding motion between the box-like body 8 and the main drum body 2 along a sliding direction 100. Preferably, the detachable retention means of the blade 6 extend along at least one retention direction that is substantially perpendicular to the arrangement plane of the blade 6 and are adapted to counteract the exit of the blade 6 from the body as of the case 8. Advantageously, the sliding direction 100 along which the relative sliding motion occurs, which allows the coupling or uncoupling of the box-like body 8 with respect to the main drum body 2, has at least one component that is substantially perpendicular to the direction along which the centrifugal force acts on the blade 6, i.e., substantially radial with respect to the axis 2a of the main drum body 2. Preferably, the sliding direction 100 is, in practice, substantially parallel to the rotation axis 2a of the main drum body 2. Conveniently, the detachable retaining means of the blade 6 are provided with at least one locking bolt 9 that detachably engages with a corresponding coupling passage opening 10 formed in the blade 6. Preferably, there are multiple locking bolts 9 that engage with respective engagement passage openings 10 formed along the longitudinal extension of the blade 6. It should be mentioned that, conveniently, in the peripheral region of the main drum body 2 there is, for the box-like body 8 of or of each cutting device 4, at least one fitted seat 11 formed, which is conveniently open on the surface of the main drum body 2. Advantageously, the box-like body 8 can, in practice, be extracted from or inserted into the accommodating seat 11, conveniently through an access opening formed on an axial face of the main drum body 2 by a relative sliding motion. Conveniently, a suction opening 12 is formed on the face of the box-like body 8 which is designed to face outwards, communicates with the suction chamber 5 and allows the label tape 120 to be pulled into the suction chamber 5 to allow the blade 6 to cut it. Conveniently, with the box-like body 8 inserted into the accommodated seat 11, the suction opening 12 is substantially disposed on the side surface of the main drum body 2. It should be mentioned that it is advantageously possible to provide means for the detachable snap-lock of the box-like body 8 in the accommodating seat 11, which can be automatically activated when the box-like body 8 is inserted into the accommodating seat 11. Preferably, the box-like body 8 is provided with at least one coupling portion 13 that can be coupled as at least one respective coupling seat 14 having a corresponding shape, formed in the main drum body 2 and communicating with the accommodating seat 11, to facilitate the sliding movement of the box-like body 8 that allows coupling or uncoupling with respect to the main drum body 2 and at the same time prevents the possibility of movement of the box-like body 8 with respect to the main drum body 2 along at least one direction that is substantially perpendicular to the sliding direction 100 along which the relative sliding movement occurs that allows coupling or uncoupling of the box-like body 8 with respect to the main drum body 2. Advantageously, the trailer portion 13 can have a substantially dovetail shape. More particularly, the coupling portion 13 comprises at least one rib 15 projecting from the outer surface of the box-like body 8 and extending substantially parallel to the sliding direction 100 along which the sliding motion occurs that allows coupling and uncoupling of the box-like body 8 with respect to the main drum body 2. In particular, rib 15 can be inserted into a corresponding notch 16 formed in the coupling seat 14. Advantageously, the coupling portion 13 further comprises, at the free end of the rib 15, at least a lateral expansion 17, which can couple a respective region 18 that is wider with respect to the notch 16 and is also formed in a coupling seat 14. Optionally, it is also possible to provide a pair of mutually opposing side expansions 17a and 17b, each of which couples with a respective wider region 18a, 18b of the coupling seat 14. Conveniently, the coupling portion 13 is arranged on the box-like body side opposite the side where the suction opening 12 is located. According to a first embodiment, shown in particular in Figure 3, to allow the deactivation of the removable retaining means of the blade 6, each locking bolt 9 can be axially removed from the housing body 8, so that once the housing body 8 has been removed from the accommodating seat 11 it is possible to release the coupling passage openings 10 of the blade 6 from the coupling with the locking bolts 9 simply by removing the locking bolts 9 from the housing body 8, so that it is possible to subsequently remove the blade 6 from the suction chamber 5 through the suction opening 12, allowing its easy replacement. In a second embodiment, shown in Figures 5 to 8, the box-like body 8 comprises at least two parts 8a and 8b, which can be separated from each other, once the box-like body 8 has been removed from the accommodating seat 11, in order to release the blade 6 from the coupling with the removable retaining means and, more particularly, from the coupling with the locking bolts 9. Conveniently, in this case, one of the two parts 8a, 8b of the body as a box 8, for example, the one designated 8a, has the locking bolts 9 integrally formed therein and forms at least a portion of the suction chamber 5, while the other part 8b forms the remaining portion of the suction chamber 5 and acts as a retaining splice for the blade 6. Advantageously, the two parts 8a and 8b of the box-like body 8 can be separated along a plane that is substantially parallel to a diametral plane of the main drum body 2. Figures 9 and 13 show a third modality, in which the only difference with respect to the second modality is that the parts 8a and 8b that make up the box-like body 8 are connected to each other by elastic return means 19, which are constituted, for example, by elastic flexible portions provided in the box-like body 8 or by elements made of rubber or other similar material. In this case, once the box-like body 8 has been removed from the accommodating seat 11, it is sufficient to move the two parts 8a and 8b of the box-like body 8 away from each other, overcoming the force applied by the elastic return means 19, to allow the release of the blade 6 from the coupling with the locking bolts 9 integrally formed in one of the two parts 8a and 8b. In accordance with a fourth embodiment, the blade 6 is kept in coupling with said detachable retaining means by contact of at least a portion of these with at least a region of the main drum body 2. In this case, preferably in the box-like body part 8 that faces the axis of the main drum body 2, an open rear region 20 is formed lateral to the blade 6, so that the rear portion 6a of the blade 6, opposite its cutting edge, can come into contact with a region of the inner wall of the accommodating seat 11 of the coupling seat 14, when the box-like body 8 is inserted into the accommodating seat, so that the blade 6 is held in a locked position between the main drum body 2 and the box-like body 8 and engaged with the locking bolts 9. In this case, once the box-like body 8 has been removed from the accommodating seat 11, the blade 6, since it is no longer held locked by contact with the main drum body 2, can be rotated, causing its rear portion 6a to come out of the open rear region 20 defined in the box-like body 8, to uncouple the locking bolts 9 from the coupler passage openings 10, thus allowing the possibility of removing the blade 6 from the suction chamber 5 through the suction opening 12. It should be noted that the air suction means 7 are conventionally provided by a vacuum distribution unit 21, on which the main drum body 2 is rotatably mounted. In the vacuum distribution unit 21 there is a vacuum chamber 22 connected to a vacuum pump 23 and provided with a vacuum inlet opening 24 formed on the face of the vacuum distribution unit 21 directed towards the main drum body 2. Conveniently, in the box-like body 8 there is, on one face thereof, a communication opening 25, connected to the suction chamber 5 and capable of fitting itself into a passage port 25a formed in the main drum body 2, so that, with the box-like body 8 inserted into its own fitting seat 11, when the corresponding cutting device 4 passes, during the rotation of the main body 2 about its own axis, through the vacuum inlet opening 24 formed in the vacuum distribution unit 21, the connection is created between the suction chamber 5 of the box-like body 8 and the vacuum chamber 22 and thus the vacuum pump 23. It should be mentioned that on the main drum body 2 in front of the housing seat 11 of the body as a box 8 of each cutting device 4 along the direction of rotation of the main drum body 2, it is possible to conveniently provide a corresponding slider 26, slightly raised with respect to the remaining part of the lateral surface of the main body 2, which allows, in cooperation with a glue roller, not shown and designed to be arranged laterally to the main drum body 2, the application of glue to the front and rear edges of the labels obtained from cutting the label tape 120, as already described, for example, in US10343808. The use of the cutting drum according to the invention is as follows. It is necessary to replace one of the blades 6 of the cutting devices 4 of the cutting drum in accordance with the invention, provided, with the main body 2 stationary, the decoupling of the corresponding box-like body 8 from the main body of drum 2 by means of a relative sliding movement between the box-like body 8 and the main body 2 along the sliding direction, until the extraction of the box-like body 8 from the corresponding accommodating seat 11 formed in the main body of drum 2 is obtained. Once the box-like body 8 has been removed from the accommodating seat 11, the blade 6 is detached from the box-like body 8. To do this, the removable retaining means of the blade 6 are first deactivated, thereby uncoupling the locking bolts 9 from the coupling passage openings 10 formed in the blade 6. The uncoupling of the locking bolts 9 is carried out, depending on the modalities, by extracting the locking bolts 9 from the body as a box 8, as in the first modality, or by separating the two parts 8a and 8b that make up the body as a box 8, as in the second and third modalities, or by rotating the blade 6, so that its rear portion 6a, which is opposite the cutting edge, comes out of the open rear region 20 of the body as a box 8, as in the fourth modality. Once the blade 6 has been released from the coupling with the locking bolts 9, the blade 6 is removed from the suction chamber 5, for example, through the suction opening 12. At this point, a new blade 6 can be inserted into the suction chamber 5 of the body as box 8 and locked to the body as box 8 by virtue of the removable locking means. In particular, in the case of the first mode, to lock the new blade 6 of the body as a box 8, after inserting the new blade 6 into the suction chamber through the suction opening 12, the locking bolts are reattached to the body as a box 8, so that they engage with the respective coupling passage openings 10 formed in the new blade 6. In the case of the second and third modes, instead, the new blade 6 is inserted between the two parts 8a and 8b that make up the box-like body 8, so that the coupling passage openings 10 of the new blade 6 engage with the block bolts 9 that are integral with one of the two parts 8a and 8b, and are joined together to again make up the box-like body 8. It should be mentioned that, in the case of the third modality, the joining of the two parts 8a and 8b occurs due to the elastic force applied by the elastic return means. In the case of the fourth modality, however, the new blade 6 is inserted into the suction chamber 5 in a position that is inclined with respect to the suction opening 12, so that the portion of the new blade 6 comes out of the rear open region that is present in this case in the box-like body 8, and then the blade is rotated to position it at right angles to the suction opening and to couple its coupling passage openings 10 with the locking bolts 9. At this point, the box-like body 8 can be further coupled to the main drum body 2 by relative sliding motion along the sliding direction, to insert the box-like body 8 into the corresponding accommodating seat 11. In practice, the invention has been found to achieve the intended goal and objectives, providing a cutting drum that allows maintenance of the cutting drum blades to be carried out with a small number of simple operations. The invention thus conceived is subject to numerous modifications and variations, all of which are within the scope of the appended claims; all details may also be replaced with other technically equivalent elements. In practice, the materials used, as well as the contingent shapes and dimensions, may be in accordance with the requirements and the state of the art. The descriptions in Italian Patent Application No. 102020000022891, from which this application claims priority, are incorporated herein by reference. Where the technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the clarity of the claims and, consequently, such reference signs have no limiting effect on the interpretation of each element exemplified by such reference signs.

Claims

1. A cutting drum for a labeling machine, comprising a main drum body (2) movable by rotating about its own axis (2a) and designed to receive in adhesion on its own lateral surface a label tape (120) on which multiple labels are printed in succession, along a perimeter of said main drum body (2), wherein there is at least one cutting device (4) comprising a respective suction chamber (5) open on an outer lateral surface of the drum and housing at least one blade (6), wherein said suction chamber (5) can be connected to air suction means (7) to draw said label tape (120) into an interior of said suction chamber (5) and against said blade (6) to produce a cut of said label tape (120),characterized in that said at least one cutting device (4) comprises a respective box-like body (8) for supporting said blade (6) internally forming said suction chamber (5), wherein said box-like body (8) is detachably supported by said main drum body (2), wherein said blade (6) is coupled to said box-like body (8) by means of detachable retaining means.

2. The cutting drum according to claim 1, further characterized in that said box-like body (8) can be coupled or uncoupled with respect to said main drum body (2) by means of a relative sliding motion between the box-like body (8) and said main drum body (2) along a sliding direction (100).

3. The cutting drum according to one or more of the preceding claims, further characterized in that said detachable retaining means extend along at least one retaining direction that is substantially perpendicular to a plane of arrangement of said blade (6).

4. The cutting drum according to one or more of the preceding claims, further characterized in that said sliding direction (100) has at least one component that is substantially perpendicular to a direction that is substantially radial with respect to the axis (2a) of said main drum body (2).

5. The cutting drum according to one or more of the preceding claims, further characterized in that said sliding direction (100) is substantially parallel to the axis (2a) of rotation of said main drum body (2).

6. The cutting drum according to one or more of the preceding claims, further characterized in that said detachable retaining means comprise at least one locking bolt (9) that is detachably coupled to a corresponding coupling passage opening (10) formed in said blade (6).

7. The cutting drum according to one or more of the preceding claims, further characterized in that, in the peripheral region of said main body (2), there is, for the box-like body (8) of said at least one cutting device (4), at least one complementaryly formed accommodating seat (11), wherein said box-like body (8) can be extracted from and inserted into said accommodating seat (11) by said relative sliding motion.

8. The cutting drum according to one or more of the preceding claims, further characterized in that a suction opening (12) is formed in the face of said box-like body (8) which is designed to face outwards and communicates with said suction chamber (5), with said box-like body (8) inserted in said accommodating seat (11), wherein said suction opening (12) is substantially disposed on the lateral surface of said main drum body (2).

9. The cutting drum according to one or more of the preceding claims, further characterized in that it comprises means for the detachable snap-lock of the housing body (8) in said accommodating seat (11), which can be automatically activated when said housing body (8) is inserted into said accommodating seat (11).

10. The cutting drum according to one or more of the preceding claims, further characterized in that said box-like body (8) is provided with at least one coupling portion (13) that can be coupled with at least one respective coupling seat (14) having a corresponding shape, formed in said main body (2) and communicating with said coupling seat (11).

11. The cutting drum according to one or more of the preceding claims, further characterized in that said coupling portion (13) has a substantially dovetail shape.

12. The cutting drum according to one or more of the preceding claims, further characterized in that said coupling portion (13) comprises at least one rib (15) projecting from the outer surface of said box-like body (8) and extending substantially parallel to said sliding direction (100), wherein said at least one rib (15) can be inserted into a corresponding notch (16) formed in said coupling seat (14).

13. The cutting drum according to one or more of the preceding claims, further characterized in that said coupling portion (13) comprises, at a free end of said at least one rib (15), at least one lateral expansion (17) that can couple a respective wider region (18), with respect to said notch (16), formed in said coupling seat (14).

14. The cutting drum in accordance with one or more of the preceding claims, further characterized in that said coupling portion (13) is disposed on the side of said box-like body (8) that is opposite with respect to the side on which said suction opening (12) is formed.

15. The cutting drum according to one or more of the preceding claims, further characterized in that said box-like body (8) comprises at least two parts (8a, 8b) that can be separated from each other to release said blade (6) from said detachable retaining means.

16. The cutting drum according to one or more of the preceding claims, further characterized in that said parts (8a, 8b) are connected to each other by elastic return means (19).

17. The cutting drum according to one or more of the preceding claims 15, characterized in that said blade (6) is kept in coupling with said detachable retaining means by contact of at least a portion thereof with at least a region of said main drum body (2).

Images