[0001] The present invention relates to a device for cutting labels for labeling machines
with sleeve labels.
[0002] Labeling machines are known in which the labels, which are sleeve-shaped, are fitted
around the containers to be labeled and subsequently heat-shrunk, in order to make
them adhere to the containers.
[0003] Such machines have, usually, a cutting device that makes it possible to obtain the
labels to be applied on the containers by way of cutting a continuous tubular element,
made of an adapted plastic material, which is unrolled, in a flattened condition,
from a coil and which is opened, by way of an adapted spreader element, before the
cutting is performed.
[0004] The cutting devices have, typically, a base frame that supports means for the entrainment
of the tubular element in the open condition, and on which a supporting element is
mounted for a plurality of cutting blades that are distributed around a passage area
that is defined in the supporting element and is intended to be axially crossed by
the tubular element that is moved by the entrainment means.
[0005] In particular, such supporting element is actuated rotationally by motor means, with
respect to the base frame, about a rotation axis that is substantially parallel to
the axis of the tubular element, in order to allow the blades to cut the tubular element
along a circumferential line, so as to remove from it, in succession, the sleeve labels
which are, thus, fitted over the containers below which are in transit on a conveyor.
[0006] Each cutting blade is mounted on a respective blade holder arm that can move rotatably,
with respect to the supporting element, about a corresponding rotation axis, which
is substantially parallel to the axis of the tubular element, in order to move the
cutting blades from a retracted rest position, in which they do not engage the tubular
element, to an extended position for work, in which they are in contact with the tubular
element, so as to perform the cut on it, and vice versa.
[0007] In particular, each blade holder arm is fixed to a corresponding supporting shaft
that is substantially parallel to the axis of the tubular element to be cut and which,
in turn, is rotatably supported by the supporting element about its own axis.
[0008] The rotation of the blade holder arms from the retracted position to the extended
position is obtained by way of conical drive wheels, which are connected to one end
of respective movement levers, which are fixed, at their other end, to the shafts
for supporting the blade holder arms, and which engage, with their lateral surface,
on the complementarily shaped outer surface of an annular cam, which is substantially
coaxial to the axis of the tubular element and is translationally moved along its
axis by adapted pneumatic cylinders, so that the sliding of the complementarily shaped
outer surface of the annular cam on the lateral surface of the conical drive wheels
can produce a movement of the movement levers with consequent rotation, about their
axis, of the shafts for supporting the blade holder arms.
[0009] The angular motion of the blade holder arms returning from the extended position
for work to the retracted rest position is instead obtained by way of adapted elastic
means of return.
[0010] Typically, the locking of the blade holder arms to the corresponding supporting shaft
is carried out by way of a clamp that is tightened against the supporting shaft by
way of a locking bolt that is screwed in the corresponding blade holder arm.
[0011] This way of executing the locking of the blade holder arms to the corresponding supporting
shafts has not however been found to be capable of preventing, following the impacts
and torque moments involved, the blade holder arms from being subjected to unwanted
angular slippages with respect to their supporting shafts, with consequent compromising
of the correct operation of the cutting device.
[0012] The aim of the present invention is to provide a valid solution to the problem described
above, by devising a device for cutting labels for labeling machines with sleeve labels
in which the blade holder arms are locked stably and safely to the corresponding supporting
shafts.
[0013] Within this aim, another object of the invention is to provide a device for cutting
labels for labeling machines with sleeve labels which makes it possible to execute
the fixing of the blade holder arms to the respective supporting shafts with the ability
to adjust their relative position, as a function of the dimensions.
[0014] Another object of the invention is to provide a device for cutting labels for labeling
machines with sleeve labels which offers a high level of reliability of operation.
[0015] This aim and these and other objects which will become better apparent hereinafter
are achieved by the device for cutting labels for labeling machines with sleeve labels,
according to the invention, as defined in claim 1.
[0016] Further characteristics and advantages of the invention will become better apparent
from the description of a preferred, but not exclusive, embodiment thereof, which
is illustrated by way of non-limiting example in the accompanying drawings wherein:
Figure 1 is a side elevation view of the control device according to the invention;
Figure 2 is a sectional view taken along the line II-II in Figure 1;
Figure 3 is a plan view from below of the device according to the invention;
Figure 4 shows an enlarged-scale detail of Figure 3;
Figure 5 shows an enlarged-scale detail of Figure 2;
Figures 6, 7 and 8 show different steps of the operation of the device according to
the invention.
[0017] With reference to the figures, the device for cutting labels for labeling machines
with sleeve labels, according to the invention, generally designated with the reference
numeral 1, comprises a base frame 2, with which a supporting element 3 is associated
on which a plurality of blades 4 are mounted.
[0018] In particular, the blades 4 are arranged about a passage area 5, through which a
tubular element 6 to be cut in order to obtain sleeve labels 6a is made to pass, and,
as will be better explained hereinafter, they are moved about the axis of the tubular
element 6 in order to execute the cut.
[0019] In particular the tubular element 6 is fed to the cutting device by entrainment means,
which comprise, conveniently, a guide shaft 7, which passes through the passage area
5 and on which the tubular element 6 is made to slide by movement rollers 8.
[0020] Upstream of the guide shaft 7, with respect to the direction of advancement of the
tubular element 6 on the guide shaft 7, there is, advantageously, a spreader element
9, which is constituted, for example, by an elongated body with mutually opposite
walls that mutually diverge as they proceed along a direction in keeping with the
direction of advancement of the tubular element 6. The spreader element 9 makes it
possible to take the tubular element 6 from a flattened condition, in which it is
found when it originates from a feed reel, not shown, to a widened or open condition,
so as to be able to slide onto the guide shaft 7, assuming a substantially cylindrical
shape structure with circular cross-section.
[0021] Preferably, the guide shaft 7 is arranged substantially vertically and, below it,
the containers 10 to be labeled are made to pass, which receive the sleeve labels
6a that are cut in each instance from the tubular element 6, by way of, conveniently,
a pair of entrainment wheels 11, which make it possible to entrain the sleeve labels
6a taken from the tubular element 6, so that they can be fitted over the containers
10 below.
[0022] Conveniently, the supporting element 3 is constituted by an annular body 3a, which
is arranged substantially coaxially to the axis of the shaft guide 7 and, therefore,
substantially coaxially to the axis of the tubular element 6 and which, in essence,
laterally delimits the passage area 5.
[0023] In particular, the supporting element 3 is mounted rotatably on the base frame 2,
about a rotation axis that is substantially parallel to the axis of the guide shaft
7 i.e. to the advancement direction of the tubular element 6 along the guide shaft
7, and can be actuated in rotation about the aforementioned rotation axis by way of
motor means that comprise, for example, an electric motor, not shown, which is functionally
connected to a pulley 12 with its axis substantially parallel to the axis of the guide
shaft 7, which engages a belt 13 that is wound around the supporting element 3.
[0024] Each blade 4 is mounted on a respective blade holder arm 14 that is fixed, by way
of locking means, to a respective supporting shaft 15, which is substantially parallel
to the advancement direction of the tubular element 6 along the guide shaft 7 and
is, in its turn, mounted rotatably, about its own axis, on the supporting element
3, in order to allow the angular movement of the blades 4 between a retracted rest
position, in which the blades 4 are disengaged from the tubular element 6, which is
arranged on the guide shaft 7, and an extended position for work, in which the blades
4 are in contact with the tubular element 6 in order to perform the cut on it.
[0025] According to the invention, the above mentioned means for locking the blade holder
arm 14 to the respective supporting shaft 15 comprise at least one lever locking body
16, which has a first portion 16a that is fixed to the supporting shaft 15 and a second
portion 16b that is fixed to the blade holder arm 14.
[0026] In particular, the first portion 16a is spaced apart from the second portion 16b
along a direction that is substantially perpendicular to the axis of the supporting
shaft 15.
[0027] In this manner, the lever locking body 16 can act positively between the supporting
shaft 15 and the blade holder arm 14 in order to prevent the possibility of unwanted
relative angular slippages between the supporting shaft 15 and the blade holder arm
14, during the operation of the cutting device.
[0028] In more detail, the lever locking body 16 can be constituted, as in the example shown,
by a plate and is, conveniently, fixed, with its first portion 16a, to one end 15a
of the supporting shaft 15 and, with its second portion 16b, to an area of the corresponding
blade holder arm 14 which is arranged laterally to the supporting shaft 15.
[0029] With particular reference to the embodiment shown, it can be seen that the end of
the supporting shaft 15 to which the lever locking body 16 is fixed, with its first
portion 16a, corresponds to the lower end of the supporting shaft 15, while the area
of the blade holder arm 14 to which the second portion 16b of the lever locking body
16 is fixed is arranged on the face of the blade holder arm 14 facing downwardly.
[0030] Advantageously, the fixing of the lever locking body 16 to the end 15a of the supporting
shaft 15 is performed by way of at least one fixing screw 18, substantially parallel
to and spaced apart from the axis of the supporting shaft 15, so as to be eccentric
with respect to the latter.
[0031] More preferably, the lever locking body 16 is fixed to the end 15a of the supporting
shaft 15 by way of at least a pair of fixing screws 18, which are substantially parallel
to the axis of the supporting shaft 15 and are arranged mutually opposite with respect
to the axis of the supporting shaft 15.
[0032] As illustrated, each fixing screw 18 is inserted in a respective reception hole 19,
defined in the lever locking body 16, in order to be screwed into a corresponding
female thread 18a, which is defined along the supporting shaft 15, and be engaged,
with a head 18b thereof, against the face of the lever locking body 16 which is directed
away from the corresponding blade holder arm 14.
[0033] Advantageously, the lever locking body 16 is associated with means of adjusting its
position with respect to the blade holder arm 14.
[0034] Conveniently, such adjustment means comprise an arc-like slot 20, with its center
substantially at the axis of the supporting shaft 15 and which is defined in the supporting
body 16 at the second portion 16b.
[0035] In particular, the arc-like slot 20 accommodates at least one locking screw 21, which
is fixed, by way of screwing in a corresponding threaded hole 21 a, to the blade holder
arm 14 and which extends substantially parallel to the axis of the supporting shaft
15, thus engaging, conveniently, with its abutment head 21b, the lateral edges of
the arc-like slot 20 which are arranged on the face of the lever locking body 16 that
is directed away from to the corresponding blade holder arm 14.
[0036] Conveniently, the means for locking each blade holder arm 14 to the corresponding
supporting shaft 15 can, optionally, also comprise a clamp, which is constituted,
advantageously, by a block 22, which is tightened laterally against the supporting
shaft 15 by way of a locking screw 22a that is screwed in the corresponding blade
holder arm 14.
[0037] As illustrated, at its opposite end 15b from the end 15a that is connected to the
lever locking body 16, the supporting shaft 15 of each blade holder arm 14 is connected
to a movement lever 23, which extends radially with respect to the supporting shaft
15 and makes it possible to execute the movement of the blade holder arms 14 in order
to move the blades 4 between their retracted rest position and their extended position
for work.
[0038] In particular, at one of its free ends, the movement lever 23 of each blade holder
arm 14 supports a respective control roller 24, which is mounted rotatably idle on
a rotation pin 24a with its axis substantially parallel to the supporting shaft 15.
[0039] As illustrated, each control roller 24 has lateral walls that have a progressively
convergent orientation toward the axis of that control roller, going in the opposite
direction to the movement lever 23, so as to give the control roller 24 a substantially
conical or frustum shape structure.
[0040] Resting against the lateral walls of each of the control rollers 24 is the outer
perimetric edge of an annular cam 25, which is supported by the base frame 2 substantially
coaxially to the axis of the guide shaft 7 and is, conveniently, arranged above the
supporting element 3.
[0041] In particular, the outer perimetric edge of the annular cam 25 has a shape that matches
the lateral walls of the control rollers 24 and, more specifically, has a profile
with an orientation that progressively approaches the axis of the annular cam 25,
going in the direction of the movement levers 23.
[0042] The annular cam 25 is mounted on the base frame 2 with the ability to perform a translational
motion axially towards and away from the supporting element 3.
[0043] The translational movement of the annular cam 25 is driven by actuators 26, which
are constituted for example by pneumatic cylinders which act between the supporting
frame 2 and the annular cam 25.
[0044] The sliding of the outer perimetric edge of the annular cam 25 on the lateral walls
of the control rollers 24, following a translational movement of the annular cam 25
along its axis toward the supporting element 3, causes the rotation of the movement
levers 23 about the axis of the supporting shaft 15 and the consequent angular movement
of the blade holder arms 14, again about the axis of the corresponding supporting
shaft 15, so as to bring the blades 4 from the retracted rest position to the extended
position for work.
[0045] Advantageously, there are elastic means of return of the blade holder arms 14, which
are adapted to precipitate the return of the blades 4 from the extended position for
work to the retracted rest position, following the movement of the annular cam 25
away from the supporting element 3, and which are constituted, for example, by radial
springs 27, which are interposed between the control rollers 24 and the movement levers
23 of the blade holder arms 14.
[0046] For completeness, it should be noted that the blades 4 can be, conveniently, fixed
to the corresponding blade holder arms 14 by way of protective plates 30 that are
screwed to the blade holder arms 14.
[0047] Operation of the device according to the invention is the following.
[0048] The supporting element 3 is moved constantly in rotation by its motor means about
the axis of the guide shaft 7.
[0049] The tubular element 6 unrolls in flattened form from a spool and it arrives in this
form at the spreader element 9, which opens it by way of the sliding of the tubular
element 6 on the spreader element 9.
[0050] The tubular element 6 is, thus, entrained to slide on the guide shaft 7 by the movement
rollers 8 until it reaches and goes past, with its lower free edge 6b, the passage
area 5, where the blades 4 are in the retracted rest position, and is brought, again
with the lower free edge 6b, substantially at or below the area for contact with the
entrainment rollers 11.
[0051] At this point, the movement rollers 8 are deactivated, so as to keep the tubular
element 6 in the locked position during execution of the cut.
[0052] The annular cam 25 is, then, moved by its actuators 26 toward the supporting element
3 so as to cause a movement, with a radial motion component, of the control rollers
24, so as to determine the rotation of the corresponding movement levers 23 about
the axis of the corresponding supporting shaft 15 and the consequent angular movement
of the respective blade holder arms 14, so as to bring the blades 4 from their retracted
rest position to the extended position for work.
[0053] The motion of the blades 4 around the tubular element 6 by way of the rotation of
the supporting element 3 about the axis of the guide shaft 7 produces the cutting
of the tubular element 6, with consequent removal of a sleeve label 6a, which is entrained
by the entrainment wheels 11 along the lower part of the guide shaft 7, in order to
be fitted onto an underlying container 10 which is being transported below the cutting
device.
[0054] At this point, the annular cam 25 is brought by its actuators 26 to a position away
from the supporting element 3, so that the movement levers 23, under the thrust of
the elastic means of return, can produce the rotation of the blade holder arms 14
about the axis of the corresponding supporting shaft 15 and bring the blades 4 back
to the retracted rest position.
[0055] The cycle resumes with the activation of the movement rollers 8 which again entrain
the tubular element 6 by making it slide along the guide shaft 7 until its lower free
edge 6b is brought substantially at or below the area of contact with the entrainment
rollers 11.
[0056] The actuation of the annular cam 25, with consequent angular movement of the blade
holder arms 14 and the returning of the blades 4 to the retracted rest position, makes
it possible to execute a new cut of the tubular element 6 with removal of another
sleeve label 6a, which will be entrained by the entrainment rollers 7 in order to
be fitted over a successive container 10 that is being transported below the cutting
device.
[0057] In practice it has been found that the device according to the invention fully achieves
the set aim and objects and, in particular, attention is drawn to the fact that the
presence of the lever locking body makes it possible to ensure a solid locking of
the blade holder arms to the respective supporting shafts, thus preventing the possibility
of unwanted angular slippages between the blade holder arms and the corresponding
supporting shafts.
[0058] All the characteristics of the invention, indicated above as advantageous, convenient
or similar, may also be missing or be substituted by equivalent characteristics.
[0059] The individual characteristics set out in reference to general teachings or to specific
embodiments may all be present in other embodiments or may substitute characteristics
in such embodiments.
[0060] The invention, thus conceived, is susceptible of numerous modifications and variations,
all of which are within the scope of the appended claims.
[0061] In practice the materials employed, provided they are compatible with the specific
use, and the dimensions and shapes, may be any according to requirements.
[0062] Moreover, all the details may be substituted by other, technically equivalent elements.
[0063] The disclosures in Italian Patent Application No.
VR2013A000291 from which this application claims priority are incorporated herein by reference.
[0064] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly, such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. A device for cutting labels for labeling machines with sleeve labels which comprises
a base frame (2) that supports a supporting element (3) for a plurality of blades
(4) that are arranged around an area (5) for the passage of a tubular element (6)
to be cut which is fed by entrainment means, each one of said blades (4) being mounted
on a respective blade holder arm (14) that is fixed, by way of locking means, to a
respective supporting shaft (15) that is mounted rotatably, about its axis, on said
supporting element (3), in order to allow the angular movement of said blades (4)
between a retracted rest position, in which said blades (4) are disengaged from said
tubular element (6), and an extended position for work, in which said blades (4) are
in contact with said tubular element (6) in order to perform the cut on it and as
a consequence obtain, in each instance, a sleeve label (6a), characterized in that said locking means comprise at least one lever locking body (16) that has a first
portion (16a) that is fixed to said supporting shaft (15) and a second portion (16b)
that is fixed to said blade holder arm (14), said first portion (16a) being spaced
apart from said second portion (16b) along a direction that is substantially perpendicular
to the axis of said supporting shaft (15).
2. The device according to claim 1, characterized in that said lever locking body (16) is fixed, with said first portion (16a), to one end
(15a) of said supporting shaft (15) and, with the second portion (16b), to an area
of said blade holder arm (14) which is arranged laterally to said supporting shaft
(15).
3. The device according to one or more of the preceding claims, characterized in that said lever locking body (16) has means of adjusting its position with respect to
said blade holder arm (14).
4. The device according to one or more of the preceding claims, characterized in that said lever locking body (16) comprises a plate.
5. The device according to one or more of the preceding claims, characterized in that said lever locking body (16) is fixed to said end (15a) of said supporting shaft
by way of at least one fixing screw (18) that is substantially parallel to and spaced
apart from the axis of said supporting shaft (15).
6. The device according to one or more of the preceding claims, characterized in that said lever locking body (16) is fixed to said end (15a) of said supporting shaft
(15) by way of at least a pair of fixing screws (18) that are substantially parallel
to the axis of said supporting shaft (15) and are arranged mutually opposite with
respect to the axis of said supporting shaft (15).
7. The device according to one or more of the preceding claims, characterized in that said adjustment means comprise an arc-like slot (20), with its center substantially
at the axis of said supporting shaft (15), that is defined in said lever locking body
(16) at said second portion (16b) and which accommodates at least one locking screw
(21) that is fixed to said blade holder arm (14) and which extends substantially parallel
to the axis of said supporting shaft (15).