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(11) | EP 2 610 191 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Distributor device of a vacuum drum system for labelling machines |
| (57) A distributor device (11) is arranged in a fixed position below a vacuum drum (14),
which is rotatable about a vertical axis (A); the distributor device (11) is connectable
to vacuum and/or pressure sources and has an upper body (49) defining at least two
concentric circular grooves (55), which are continuous and house a plurality of blocks
(58), so as to form arc-shaped groove portions (60) communicating with at least some
of the inlets (39) and open at the top for communicating, in use, with passages (15)
of the vacuum drum (14); the angular positions of the blocks (58) are adjustable in
the circular grooves (55) to allow length adjustment and/or position adjustment of
the arc-shaped groove portions (60).
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TECHNICAL FIELD
[0001] The present invention relates to a distributor device of a vacuum drum system for labelling machines.
BACKGROUND ART
[0002] As it is generally known, labelling machines are used to transport, prepare and apply labels to containers, such as bottles, or articles of all sort.
[0003] Typically used with beverage bottles or vessels are tubular labels (commonly called "sleeve labels"), which are obtained by:
- cutting the web unwound from a supply roll into a plurality of rectangular or square labels;
- bending each label in a cylindrical configuration such that the opposite vertical edges overlap one another; and
- welding the overlapped edges of each cylindrical label.
[0004] Also widespread used are gluing labels, which, after being cut from a web at appropriate lengths, are glued by gluing means, such as a gluing roller, spray and injector systems or the like, and are finally transferred to respective containers or articles.
[0005] In both cases, the labels are retained on a vacuum drum, or transfer roller, by means of vacuum applied on the labels. In particular, a conventional vacuum drum has an approximately cylindrical lobed configuration and receives a succession of labels at an input station and, after a given rotation about its axis, transfers the labels to the labelling machine at an output station, so that they can be applied to respective articles or containers.
[0006] The vacuum drum is typically mounted, in a rotatable manner about its axis, on a stationary distributor device having first air passages connected to a vacuum source and a pressurized air source. On the other hand, the vacuum drum is provided with second air passages, which communicate with the first air passages at certain angular positions of the drum about its axis and exit into a plurality of side ports formed through an outer lateral surface of the vacuum drum.
[0007] In a known solution, the distributor device is defined by a single distributor plate having arc-shaped passages that distribute the air pressure. The length of some arc-shaped passages can be adjusted by means of suitable blocks, in order to adapt the vacuum drum system to a specific label length.
[0008] Notwithstanding this adjustment, different distributor plates must be provided, in relation to the configuration chosen for the labeling machine. With reference with
[0009] Figures 1a-1d, a labeling machine is schematically shown in plan view and is indicated by reference number 1. The labeling machine 1 has a carousel 2, i.e. a rotating structure which transfers the containers 3 towards the vacuum drum 4. The carousel 2 rotates about its axis with an angular speed Vc. In the meantime, the vacuum drum 4 rotates about its axis with an angular speed Vd. The labeling machine 1 can operate with a "positive spin" or a "negative spin", and can be "right hand" or "left hand", so that four possible settings or configurations are possible.
[0010] The "right hand" feature (fig. 1a and 1c) and the "left hand" feature (fig. 1b and 1d) identify the rotation direction of the vacuum drum 4.
[0011] With a positive spin (fig. 1a and 1b), each container 3 has an angular speed Vp about its axis, and the carousel 2 and the container 3 have the same rotation direction. Therefore, the tangential speeds of the carousel 2 and the vacuum drum 4 at the container 3 are oriented in the same direction.
[0012] With a negative spin (fig. 1c and 1d), each container 3 has an angular speed Vn about its axis with a rotation direction opposite to the one of the carousel 2. The angular speed Vn of the container 3 has to be greater than the angular speed Vp in order to wrap the label around the container 3. This is due to the fact that the tangential speeds of the carousel 2 and the vacuum drum 4 at the container 3 are oriented in opposite directions.
[0013] As four different configurations or settings can be provided, also four correspondent distributor plates have to be manufactured, with different constructional features for defining their air passages. Therefore, for each distributor plate, a correspondent die has to be designed and manufactured, so that long time and high costs are necessary to design and obtain all the four distributor plates by molding.
DISCLOSURE OF INVENTION
[0014] It is an object of the present invention to provide a distributor device of a vacuum drum system for labelling machines, which allows to overcome the above drawback in a straightforward and low-cost manner, trying to obtain a compact design in order to leave the same layout of the transmission driving the vacuum drum and the same layout of the pipes connecting to distributor device to the vacuum source and to the pressurized air source.
[0015] This object is achieved by a distributor device of a vacuum drum system for labeling machines, as defined in claim 1.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which:
- Figures 1a-1d are schematic plan views, showing a labeling machine in respective configurations;
- Figure 2 is a cross-section of a distributor device of a vacuum drum system for labelling machines, in accordance with the teachings of the present invention;
- Figure 3 is a perspective top view of the distributor device of Figure 2; and
- Figure 4 shows, in an exploded view and an enlarged scale, the distributor device of Figure 3.
BEST MODE FOR CARRYING OUT THE INVENTION
[0017] Number 10 in Figure 2 indicates, as a whole, a vacuum drum system (partially shown) adapted to be used for handling and transferring labels along an arc-shaped path about a vertical axis A towards a labelling machine (of known type, and not shown in Figures 2-4) for applying the labels to respective articles, more specifically to containers, such as bottles (not shown).
[0018] In particular, vacuum drum system 10 is adapted to receive a succession of labels at an input station and to transfer the labels to the labelling machine at an output station, located at a given angular distance from the input station about axis A. At the output station, the labels are applied to respective articles on the labelling machine.
[0019] Vacuum drum system 10 basically comprises a stationary distributor device 11 provided with air passages 12 connected to a vacuum source 13 (schematically shown) and to a pressurized air source (not shown). Vacuum drum system 10 further comprises a vacuum drum 14, or transfer roller, which is arranged on distributor device 11, is rotatable about axis A and is provided with air passages 15 (partially shown) communicating, at one end, with air passages 12 at certain angular positions of the drum 14 and, on the another end, with a plurality of side ports (not shown) made through an outer lateral surface 18 of the drum 14. In particular, surface 18 has an approximately cylindrical lobed shape.
[0020] In practice, when air connection is established between source 13 and one of the passages 15, air is suctioned from the correspondent side ports, so as to produce an attractive force on a label towards surface 18. Such label is then released at the output station, by stopping the communication of the side ports with the vacuum source 13, and preferably by putting such side ports in communication with the pressurized air source, in order to wrap the label onto the respective article.
[0021] Drum 14 is driven by a motor, such as a brushless motor or the like, placed below the distributor device 11. In an another embodiment (not shown), drum 14 is driven by the motor of the labelling machine through suitable gears or transmissions.
[0022] Always with reference to Figure 2, drum 14 comprises a hub 21, connected to the motor by means of a vertical transmission member 22, which is housed in a tubular upright 23 and is coupled to upright 23 by means of rolling bearings 24 (schematically shown).
[0023] Drum 14 further comprises a lower plate 26, arranged in contact with an upper horizontal surface 27 of distributor device 11 and provided with a plurality of apertures 28, which define the inlets of passages 15, extend along vertical axes, and communicate with air passages 12 at certain angular positions of the drum 14. Plate 26 has an annular shape, so as to have a central through hole 29 extending along axis A and engaged by an upper end portion 30 of upright 23 with clearance.
[0024] Distributor device 11 is coaxial with plate 26 and also has an annular shape, so as to define a central through hole 31 coaxial with hole 29 and engaged by portion 30. Distributor device 11 is supported in fixed position in a known and not shown manner, and comprises a lower body or ring 35 coupled by means of fittings 36 to the vacuum source 13 and to the pressurized air source.
[0025] Preferably, body 35 comprises a bottom wall 37 having a plurality of apertures engaged by fittings 36, which preferably extend along vertical axes and define respective inlets 39 of passages 12. With reference with Figure 4, body 35 comprises an inner annular wall 40, an outer annular wall 41, and inner walls 42, projecting upwardly from wall 37. Walls 40,41,42 are made in one piece with wall 37 and define a plurality of chambers 43, which permanently communicate with inlets 39 and are open at the top. Walls 42 separate chambers 43 in airtight manner and have a lower height in relation to the upper edges of walls 40,41, so that the upper edges of walls 40,41 define an annular recess 44 above walls 42.
[0026] Other divider elements 45 can be added and fixed to body 35 in order to obtain a different number and/or a different shape for the chambers 43. Preferably, body 35 is symmetric with respect to a vertical diametrical plane P, in order to have a symmetric layout for the chambers connected to the vacuum source 13 and a symmetric layout for the chambers connected to the pressurized air source.
[0027] Body 35 is provided with holes 47 engaged by releasable fastening devices 48, connecting body 35 in a fixed position and in releasable manner to a body or ring 49, which defines the upper part of distributor device 11.
[0028] Body 49 is coaxial with body 35 along axis A and comprises a horizontal bottom wall 50, having an inner edge and an outer edge which are coupled to the upper edges of walls 40,41. In particular, wall 50 has a lower projection 51, which engages recess 44 to center body 49 in relation to body 35. Body 49 further comprises a plurality of vertical walls 53, which project upwardly from wall 50. Walls 53 and 50 define at least two (and preferably three) concentric circular grooves 55, which are continuous about axis A and have, each, a constant width in radial direction.
[0029] Wall 50 has a plurality of vertical through holes 56 adapted to put grooves 55 in communication with the below chambers 43. In each groove 55, at least some of the holes 56 are arranged in evenly spaced positions about axis A and are provided with respective threads in order to screw fastening devices 57, which connect a plurality of inserts or blocks 58 to body 49 in releasable manner.
[0030] Blocks 58 are housed in grooves 55, are provided with through holes or slots 59 adapted to be engaged by the fastening devices 57, and divide grooves 55 into arc-shaped groove portions 60 in airtight manner (Fig. 3). The upper surfaces of blocks 58 and walls 53 are coplanar and are arranged in contact with plate 26, so as to define the above mentioned surface 27. The arc-shaped groove portions 60 define the end of passages 12 and are open at the top, in order to communicate with apertures 28.
[0031] Blocks 58 are arc-shaped and have the same width and the same radius of curvature of the correspondent grooves 55, so that they can be moved along grooves 55 during assembly of the distributor device 11, in order to adjust and set the desired positions. In this way, the position and/or the length of the arc-shaped groove portions 60 can be chosen and adjusted as a function of the kind of the labeling machine, as a function of its configuration, and as a function of the length of the labels to be applied.
[0032] In particular, all other conditions being equal, it is possible to select two different positions for the blocks 58, in order to configure the distributor device 11 for a labeling machine operating with a positive spin (Fig. 1a and 1b) or, respectively, for a labeling machine operating with a negative spin (Fig. 1c and 1d).
[0033] For changing the layout of passages 12 and adapting them to different configurations of the labeling machine, distributor device 11 further comprises a horizontal ring plate 61, which is housed in recess 44 and is sandwiched in fixed position between bodies 35,49 by the fastening action of devices 48.
[0034] Ring plate 61 has two parallel faces 62,63, which are airtight coupled respectively to the upper face of inner walls 42 and to the lower face of projection 51. Ring plate 61 substantially has the same shape and area of projection 51, closes some holes 56 and some chambers 43, and has through apertures 64 defining ports to put selected holes 56 into communication with the below chambers 43, in order to define the desired passages 12. Preferably, face 62 and/or face 63 are covered by a sealing layer (not shown), such as a sponge rubber layer.
[0035] Plate 61 can be placed in a first position or a second position, which is turned upside-down with respect to the first position about a diametrical axis B lying on plane P: therefore, in the second position the layout of the apertures 64 is symmetric to their layout in the first position, with respect to axis B. These two positions are used to adapt distributor device 11 to a labeling machine configuration which is right-hand or, respectively, left-hand.
[0036] Therefore, considering the adjustment given by both the devices defined by the blocks 58 and the plate 61, it is possible to adapt the distributor device 11 to four different configurations of the labeling machine (a "positive" and "right-hand" configuration, a "positive" and "left-hand" configuration, a "negative" and "right-hand" configuration, and a "negative" and "left-hand" configuration) without the need of designing and molding additional distributor devices.
[0037] Considering the adjustment given only by the blocks 58, the latter can be arranged about axis A at different locations along the continuous circular grooves 55, in order to adapt the distributor device 11 to different labelling machines ("flexible" machine, "matrix" machine, etc...) and to different length of the labels to be received and applied.
[0038] Indeed, the variable locations for the blocks 58 all over the circumference of body 49 allow a high degree of freedom in configuring the distributor device 11 with respect to the prior art solutions that do not have circular continuous grooves, so that distributor device 11 has significantly lower manufacturing time and costs.
[0039] Below body 49, distributor device 11 comprise body 35, that is designed to be connected the already installed vacuum source 13 and pressurized air source, without changing their layout. In the meantime, between bodies 35,49 plate 61 defines interface ports that connect the vacuum source 13 and to the pressurized air source to the desired areas about axis A and can be possibly changed. Therefore, the elements of distributor device 11 can be configured with a high range of options.
[0040] Furthermore, bodies 35,49 and plate 61 are separate parts that are easy to be disassembled for cleaning and/or for re-configuring the distributor device 11.
[0041] Finally, thanks to the constructional features of the bodies 35,49, the distributor device 11 can be assembled in a simple manner, takes up relatively small room, and do not change the layout of the transmission driving drum 14.
1. A distributor device (11) of a vacuum drum system (10) for labelling machines, the
distributor device being adapted to be arranged in a fixed position below a vacuum
drum (14), which is rotatable about a vertical axis (A), and comprising:
• first passages (12), which have inlets (39) connectable to a vacuum source (13) and to a pressure source and, in use, communicate with second passages (15) of said vacuum drum (14) at certain angular positions of said vacuum drum (14);
• configuration means (58,61) comprising a plurality of blocks (58);
characterized by comprising an upper body (49) defining at least two circular grooves (55), which
are concentric and are continuous about said vertical axis (A); said blocks (58) being
housed in said circular grooves (55) so as to separate arc-shaped groove portions
(60), which are in communication with at least part of said inlets (39); the angular
position of said blocks (58) being adjustable in said circular grooves (55).
2. Distributor device according to claim 1, characterized in that said blocks (58) are arc-shaped and have the same radius of curvature of the correspondent
circular grooves (55).
3. Distributor device according to claim 1 or 2, characterized in that said upper body (49) comprises a horizontal wall (50) defining the bottom surface
of said grooves (55) and having through holes (56) to put said arc-shaped groove portions
(61) into communication with said inlets (39).
4. Distributor device according to claim 3, characterized by further comprising a lower body (35) defining a plurality of chambers (43) permanently
communicating with said inlets (39); said configuration means (58,61) further comprising
an intermediate plate (61), which is arranged between said upper and lower bodies
(35,49) and defines through apertures (64) that put some of said holes (56) into communication
with said chambers (36).
5. Distributor device according to claim 4, characterized in that said intermediate plate (61) can be placed in a first position or a second position,
which is turned upside-down with respect to the first position about a diametrical
axis (B).
6. Distributor device according to claim 4 or 5, characterized in that at least one face of said intermediate plate (61) is covered by a sealing layer.
7. Distributor device according to anyone of claims 4 to 6, characterized by comprising releasable connecting means (48) that connect said upper and lower bodies
(35,49) and said intermediate plate (61) in fixed position and in releasable manner.
8. Distributor device according to anyone of claims 3 to 7, characterized in that at least some of said through holes (56) are provided with respective threads; fastening
means (57) being screwed to said threads in order to fix said blocks (58) to said
upper body (49) in releasable manner.
9. Distributor device according to anyone of claims 3 to 8, characterized in that, in each said circular groove (55), said through holes (56) are evenly spaced about
said vertical axis (A).
10. Vacuum drum system (10) for labeling machines, comprising:
• a vacuum drum (14), which is rotatable about a vertical axis (A),
• a distributor device (11), which is coaxial with said vacuum drum (14), is arranged in a fixed position below said vacuum drum (14), and is made according to anyone of the previous claims.