[0001] The present invention relates to a deposit group of the type specified in the preamble
of the first claim.
[0002] In particular, the subject matter of the invention introduces an innovative device
for depositing a liquid (such as a glue or a dye, a perfume/essence) on a suitably
continuous sheet.
[0003] The sheets can be made either of a paper material (corrugated, preferably smooth),
a polymeric material, or a cellulose hydrate such as cellophane.
[0004] As is well known, the deposit group, also known as gluer, is suitable to place a
gluing liquid on a sheet, allowing its gluing to an additional sheet, thus providing
a processed sheet. Alternatively, it is used to deposit a dyeing liquid on a continuous
sheet so as to colour it entirely or preferably to reproduce thereon an image or a
writing.
[0005] To date, the deposit group consists of a tank, also called chamber, containing the
liquid to be deposited on the sheet; a roller for withdrawing the liquid from the
tank; a laying roller interposed between the drawing roller and the paper/polymer
sheet, which is suitable to withdraw the liquid from the drawing roller and to place
it on the sheet; a contrast cylinder on which the laying roller rests, coming into
contact with the sheet and ensuring the laying down of the liquid on the sheet; and
a crankcase supporting the laying roller, the drawing roller and the contrast cylinder.
[0006] The tank and the drawing and laying rollers are mounted on a support structure hinged
to the crankcase, and the deposit group comprises a pneumatic cylinder for controlling
the rotation of the tank and the rollers with respect to the contrast cylinder between
a working position, in which the laying roller is close to the contrast cylinder,
and a machine stop position, in which the tank and the rollers are moved away from
the cylinder at a predetermined distance from the contrast cylinder.
[0007] This distance is important in the case of gluing for preventing, during machine stoppage,
the sheet, when in contact with the laying roller, from sticking to the same laying
roller and/or to the contrast cylinder. Such distance is equal to 25-50 mm so that,
irrespective of the thickness of the sheet, said contact between the sheet and the
laying roller is prevented.
[0008] The above-mentioned prior art has a few major drawbacks.
[0009] A first drawback is the complex execution of the maintenance or repair operations
on the deposit groups known to date.
[0010] In fact, in order to access it, it is necessary to remove the pneumatic control cylinder
from the support structure, rotate and overturn said support structure together with
the tank, the drawing roller and the laying roller, moving these elements away from
the contrast cylinder.
[0011] The above-mentioned overturning of the tank, the drawing roller and the laying roller
defines a free area of limited size, which ensures a limited freedom of movement to
the operator.
[0012] Another drawback is that, at each restart of production, the pneumatic cylinder takes
a few seconds to bring back the laying roller into the working position, and consequently
part of the sheet slides along the contrast cylinder before the liquid can be laid
down thereon.
[0013] This drawback is important when considering the high feed rate of the sheet and the
presence of many metres of unglued/uncoloured sheet.
[0014] The above drawback is further penalising since distributors often reject a lot thus
produced due to the presence of non-perfectly glued/coloured rolls.
[0015] This rejection therefore results in a considerable waste of paper and, especially,
in a substantial increase in costs.
[0016] In this context, the technical task underlying the present invention is to devise
a deposit group, which is capable of substantially obviating the above-mentioned drawbacks.
[0017] Within the scope of said technical task, a major object of the invention is to provide
a deposit group, which allows maintenance and repair operations to be performed in
a simple and quick way.
[0018] Another important object of the invention is to obtain a deposit group, which avoids
the presence of long sections of sheet devoid of gluing, dyeing or other liquid to
be deposited.
[0019] The technical task and the specified objects are achieved by means of a deposit group
as claimed in the appended claim 1.
[0020] Preferred embodiments are set forth in the dependent claims.
[0021] The features and advantages of the invention will be apparent from the detailed description
of a preferred embodiment of the invention, with reference to the accompanying drawings,
in which:
Fig. 1 shows a deposit group according to the invention;
Fig. 2a shows a section of the deposit group according to the invention;
Fig. 2b shows the deposit group in a different configuration;
Fig. 2c shows a further configuration of the deposit group;
Fig. 3a shows an assembly in section of the deposit group;
Fig. 3b shows the assembly of Fig. 3a in a different position; and
Fig. 4 shows a detail of the deposit group.
[0022] In the present document, the measures, values, shapes and geometric references (such
as perpendicularity and parallelism), when associated with words like "about" or other
similar terms such as "almost" or "substantially", are to be understood as unless
measurement errors or inaccuracies due to production and/or manufacturing defects
and, especially, unless a slight difference from the value, the measure, the shape,
or the geometric reference with which it is associated. For example, these terms,
if associated with a value, preferably indicate a difference of not more than 10%
of the value itself.
[0023] Furthermore, when used, terms such as "first", "second", "higher", "lower", "main"
and "secondary" do not necessarily identify an order, a priority relationship or a
relative position, but can simply be used to distinguish more clearly the different
components from each other.
[0024] With reference to the aforementioned figures, the deposit group according to the
invention, as a whole, is indicated by the numeral
1.
[0025] It is used to deposit a fluid, preferably a liquid (e.g. a glue or a colour) on a
raw, preferably continuous sheet 1a, thus obtaining a processed sheet
1b also preferably continuous.
[0026] It should be noted that the expression "raw sheet" simply identifies the sheet before
the liquid is deposited thereon by the deposit group 1. The raw sheet differs from
the processed sheet 1b, which in fact comprises the raw sheet 1 a and the liquid deposited
thereon.
[0027] The deposit group 1 can deposit a (fluid, in detail liquid) glue on the raw sheet
1a, allowing its gluing to at least an additional, preferably continuous sheet
1c. It is therefore capable of gluing together two or more sheets 1a and 1c, forming
a processed sheet 1 b comprising said at least two sheets 1 a and 1 c, hence with
two or more layers.
[0028] It should be noted that one or more of the sheets 1 a, 1b and 1 c can also have two
or more layers.
[0029] Alternatively, the deposit group 1 can be used to deposit a (fluid, in detail liquid)
dye on the raw sheet 1 a so as to form a single processed sheet 1 b exhibiting a writing
and/or a coloured image.
[0030] The sheets 1 a, 1b and 1 c can be made either of a paper material (corrugated, or
preferably smooth), a polymeric material, or a cellulose hydrate such as cellophane.
In detail, they are made of paper and the liquid is a glue.
[0031] The group 1 may be part of a processing line of continuous sheets. This line can
comprise multiple deposit groups 1, so as to deposit several liquids and, for example,
obtain a processed sheet 1b with more than two layers or exhibiting a multi-coloured
reproduction.
[0032] The deposit group 1 is suitable to define a sliding path (highlighted with arrows
in Fig. 2b) of at least one sheet and therefore may comprise one or more cylinders
(described below) suitable for defining the sliding path, and preferably at least
partly motorised, so as to control the movement of the at least one sheet along said
sliding path.
[0033] The deposit group 1 may comprise a contrast cylinder
2 along which at least one raw sheet 1a slides; at least one laying block
3 for depositing at least one liquid on the raw sheet 1a; and, suitably, a control
unit suitable to control the operation of the group 1 based on a command given by
the operator.
[0034] The contrast cylinder 2 defines a preferably substantially horizontal rotation axis
2a. The contrast cylinder 2 can be motorised.
[0035] The contrast cylinder 2 can have on its outer surface a reproduction suitable to
be reproduced on the raw sheet 1a. This reproduction is identifiable as a bas/high
relief reproducing, for example, dots and/or figures.
[0036] In a further alternative, the outer surface of the contrast cylinder 2 is smooth.
[0037] At least in the case of gluing of the raw sheet 1a to the additional sheet 1c, the
deposit group 1 may comprise a slide cylinder
4 along which the additional sheet 1c slides before joining the raw sheet 1a downstream
of the laying block 3 with respect to the raw sheet 1a.
[0038] It should be noted that in this document the expressions "downstream" and "upstream"
are to be understood in relation to the feed directions of the sheets 1a, 1b and 1c
shown in Fig. 2b.
[0039] The slide cylinder 4 can be motorised.
[0040] The slide cylinder 4 may comprise an additional reproduction formed on the outer
surface for the sliding of the additional sheet 1c, which is suitable to be reproduced
on the additional sheet 1c. This additional reproduction can be somewhat similar to
that of the contrast cylinder 2.
[0041] Alternatively, the outer surface of the slide cylinder 4 is smooth.
[0042] The deposit group 1 may comprise a support structure
5 for the contrast cylinder 2, the at least one laying block 3 and the slide cylinder
4, if present. It should be noted that the various cylinders are associated with the
structure 5 in a resolvable manner so as to allow its replacement.
[0043] Said support structure 5 comprises two side panels
51 suitable to enclose and support the contrast cylinder 2, the at least one laying
block 3 and the slide cylinder 4, if present.
[0044] The side panels 51 are substantially perpendicular to the rotation axis 2a, and suitably
vertical.
[0045] The side panels 51 can be anchored to the ground, and in particular they define the
only points of anchorage/support of the deposit group 1 to the ground. Consequently,
the laying block 3 is spaced from the ground.
[0046] The deposit group 1 may comprise at least one laying block 3 (preferably only one)
for depositing at least one liquid, suitably a glue or dye, on at least part of the
raw sheet 1a when it slides on the contrast cylinder 2.
[0047] The laying block 3 comprises, for each liquid to be deposited, a dispenser
31 suitable to dispense the liquid; and at least one roller suitable to withdraw the
liquid from the dispenser 31 and to deposit it on the raw sheet 1a; and suitably a
feeding apparatus suitable to withdraw the liquid from a tank and bring it to the
dispenser 31.
[0048] In particular, for each liquid to be deposited, the laying block 3 may comprise a
dispenser 31; a drawing roller
32 for withdrawing the liquid from the dispenser 31; and a laying roller
33 interposed between the drawing roller 32 and the contrast cylinder 2, which is suitable
to receive the liquid from the drawing roller 32 and place it on the raw sheet 1a
when it slides on the contrast cylinder 2.
[0049] The dispenser 31 may comprise a chamber containing the liquid, and preferably at
least partially filled by the feeding apparatus; and one or more blades suitable to
ensure the correct dosage and distribution of the liquid on the at least one roller.
[0050] Each roller 32 and 33 defines an additional rotation axis substantially parallel
to the rotation axis 2a.
[0051] The drawing 32 and the laying 33 rollers are, at least when the group 1 is in operation,
in mutual contact so as to allow the passage of liquid between said rollers 32 and
33.
[0052] The drawing cylinder 32 can be screened and preferably identifiable as an anilox
cylinder.
[0053] The laying roller 33 can have on its outer surface a reproduction suitable to be
reproduced on the raw sheet 1a. This reproduction is identifiable as a bas/high relief
reproducing, for example, dots and/or figures. For example, the outer surface of the
laying roller 33 can have radial protrusions (identifiable as rings equally spaced
along axis 2a, figures or writings) substantially constituting the only deposit points
of the liquid on the raw sheet 1a.
[0054] Alternatively, the outer surface of the laying roller 33 is smooth.
[0055] The laying block 3 may comprise a support frame
34 for the dispenser 31 and the at least one roller 32 and 33, which can allow said
dispenser 31 and the at least one roller 32 and 33 to be moved simultaneously, as
described hereinafter.
[0056] The support frame 34 comprises two walls
341 suitable to enclose and support the dispenser 31 and the at least one roller 32 and
33.
[0057] The walls 341 are substantially perpendicular to the additional axis of the at least
one roller 32 and 33 and hence to the rotation axis 2a. Preferably, the walls 341
are vertical.
[0058] It is noted that the walls 341 are substantially parallel to the side panels 51.
[0059] The distance between the walls 341 is substantially different from the distance between
the panels 51 so that they can slide reciprocally, and in particular so as to superimpose
the walls 341 onto the side panels 51 with respect to the rotation axis 2a. Conveniently,
the distance between the walls 341 is substantially greater than the distance between
the panels 51.
[0060] Said distances are calculated along the rotation axis 2a.
[0061] In addition, the laying block 3 may comprise a distance-adjusting member.
[0062] The adjusting member is suitable to vary the distance between the rollers 32 and
33, thus moving the assembly of the drawing roller 32 and dispenser 31 with respect
to the laying roller 33 preferably along a direction perpendicular to the rotation
axis 2a, and more preferably to the gravitational gradient.
[0063] Alternatively, the adjusting member is suitable to move the dispenser 31 with respect
to the drawing roller 32 by varying the distance between the dispenser 31 and the
drawing roller 32, preferably along a direction perpendicular to the rotation axis
2a, and more preferably to the gravitational gradient.
[0064] Preferably, the adjusting member is adapted to move both said assembly with respect
to the laying roller 33 and the dispenser 31 with respect to the drawing roller 32.
[0065] The deposit group 1 may comprise at least one pressure member
6 for pressing the sheets 1 a and/or 1 c on the cylinders 2 and/or 4.
[0066] The deposit group 1 can comprise a pressure member 6 arranged, with respect to the
raw sheet 1 a, upstream of the laying block 3 and adapted to press the raw sheet 1
a against the contrast cylinder 2.
[0067] Alternatively, the deposit group 1 can comprise a pressure member 6 arranged, with
respect to the additional sheet 1c, upstream of the slide cylinder 4 and adapted to
press the additional sheet 1c against the said cylinder 4.
[0068] In a further alternative, the deposit group 1 can comprise a pressure member 6 arranged
downstream of the laying block 3 and adapted to press any additional sheet 1c against
the contrast cylinder 2 and hence the raw sheet 1 a, ensuring the gluing of the sheets
1a and 1c.
[0069] Preferably, the deposit group 1 comprises two of said pressure members 6, and in
detail all of the above described three pressure members 6.
[0070] Each pressure member 6 comprises a pressure cylinder
61 adapted to press said sheet 1a and/or 1c against said cylinder 2 and/or 4; and a
kinematic mechanism for moving the pressure cylinder 61 adapted to move the pressure
cylinder 61 with respect to the cylinder 2 and/or 4 and thus to adjust the pressure
exerted by the pressure cylinder 61 on the cylinder 2 and/or 4.
[0071] The rotation axis of the pressure cylinder 61 of each pressure member 6 is parallel
to and advantageously coplanar with the rotation axis of the cylinder 2 and/or 4.
Suitably, the plane on which the rotation axes of the pressure cylinder 61 and of
the cylinder 2 and/or 4 lie, against which the pressure cylinder 61 presses the sheet
1a, 1b and/or 1c, is transverse to the gravitational gradient as can be easily understood,
for example, from Fig. 2b.
[0072] The pressure kinematic mechanism may comprise a thrust piston 62 that moves the pressure
cylinder 61 with respect to the cylinder 2 and/or 4; and an L-shaped lever 63 of the
first kind, the ends of which are hinged to the pressure cylinder 61 and the thrust
piston 62, which is pivoted to the support structure 5.
[0073] The deposit group 1 may comprise a mover 7 adapted to move reciprocally the laying
block 3 and the contrast cylinder 2, defining for the deposit group 1a working configuration
(Fig. 2b), in which the working distance between the cylinder 2 and the block 3 is
substantially not greater than the thickness of the raw sheet 1a; and a maintenance
configuration (Fig. 2a) in which the maintenance distance between the contrast cylinder
2 and the laying block 3 is greater than the working distance.
[0074] The working distance is not greater than 0.1 mm.
[0075] The maintenance distance is substantially equal to at least 0.5 m, preferably substantially
comprised between 0.5 m and 1 m, and more preferably substantially equal to 0.7 m.
[0076] The working and maintenance distances are calculated between the contrast cylinder
2 and the laying roller 33 perpendicularly to the rotation axis 2a.
[0077] Advantageously, the mover 7 is engaged with the support structure 5 and support frame
34, more in particular with the walls 341 and the side panels 51, mutually constraining
the block 3 and the structure 5.
[0078] It is adapted to move the laying block 3 with respect to the contrast cylinder 2
suitably by means of a translation along a movement axis
7a preferably substantially perpendicular to the rotation axis 2a.
[0079] The mover 7 comprises at least one actuator
71 adapted to reciprocally move the block 3 and the cylinder 2.
[0080] The actuator 71 may be linear and its ends may be constrained to the walls 341 and
the panels 51, so that it operates said reciprocal motion by varying its elongation.
[0081] The actuator, and therefore the mover 7, are suitable to define stable positions
between the laying block 3 and the contrast cylinder 2 almost exclusively at its end
and start of travel, i.e. at its maximum and\or minimum extension.
[0082] They define a stable working configuration in which the mover 7 and, precisely, the
actuator 71 exert a force to maintain the working configuration, which orders the
maintenance of the working distance, i.e. a variation in the reciprocal distance between
the laying block 3 and the contrast cylinder 2, ensuring the correct deposit of the
liquid.
[0083] Preferably, the mover 7 and, precisely, the actuator 71 define a stable maintenance
configuration in which they exert a force to maintain the maintenance configuration.
The actuator 71 can be pneumatic, electronic or hydraulic.
[0084] Preferably, the mover 7 comprises two actuators 71, each subtended between a wall
341 and the adjacent side panel 51.
[0085] The mover 7 may comprise at least one abutment against which the deposit block 3
abuts when the group 1 passes into the working configuration.
[0086] Said abutment is adjustable by varying the distance between the deposit roller 33
and the contrast cylinder 2 on the basis of the thickness of the sheet.
[0087] To support the weight of the laying block 3, the mover 7 may comprise at least one
guide
72 integral with the support structure 5, and more precisely with the side panels 51;
and for each guide 72, at least one slider
73 integral with the laying block 3, and in particular with the walls 341, and suitable
to slide along the guide 72. Preferably, the mover 7 comprises two guides 72 for each
side panel 51; and two sliders 73 for each guide 72.
[0088] The guide 72 defines a sliding axis for the slider 73 substantially parallel to the
movement axis 7a.
[0089] The deposit group 1 may comprise at least one limiter
8 suitable to limit the stroke of the mover 7 by reducing the possible mutual spacing
between the contrast cylinder 2 and the laying block 3 and preventing the maintenance
configuration from being reached.
[0090] The limiter 8 enables the group 1 to vary its own configuration between the working
configuration and a stationary machine configuration interposed between the working
and maintenance configurations, thereby defining a machine stop distance (between
the contrast cylinder 2 and the laying block 3) intermediate between the working and
maintenance distances.
[0091] In particular, the limiter 8 defines an active position in which it limits the stroke
of the mover 7 and the group 1 varies its configuration, suitably exclusively between
the working and the stationary machine configurations; and a passive position in which
the limiter 8 does not limit the stroke of the mover 7 and the group 1 varies its
configuration, suitably exclusively between the working and the maintenance configurations.
[0092] It should be noted that the machine stop distance is calculated between the contrast
cylinder 2 and the laying roller 33 perpendicularly to the rotation axis 2a.
[0093] Suitably, the limiter 8 is adapted to define a machine stop distance ranging between
a maximum value and a minimum value.
[0094] The limiter 8, by preventing at least a further distancing between the laying block
3 and the contrast cylinder 2, allows the mover 7 to define a stable stationary machine
configuration wherein, in fact, the limiter 8, by preventing a further distancing
between the block 3 and the cylinder 2, causes the mover 7 to exploit the blockage
provided by the limiter 8 in order to exert a force to maintain the stationary machine
configuration opposing a variation in the distance between the laying block 3 and
the contrast cylinder 2.
[0095] The limiter 8 can be mechanical and, for example, limit the stroke of the mover 7
by engaging the contrast cylinder 2 with the laying block 3, and precisely the support
structure 5 with the support frame 34.
[0096] Preferably, the deposit group 1 comprises two limiters 8, each of which suitable
to engage a side panel 51 with the adjacent wall 341.
[0097] A limiter 8 may comprise a slot
81 and a stop
83, one of which is integral with the support structure 5 and the other with the support
frame 34.
[0098] Preferably, the slot 81 is integral with the support structure 5, and in particular
with a side panel 51. The stop 83 is suitable to be integral with the support frame
34, and precisely with a wall 341.
[0099] The slot 81 has an axis extending substantially parallel to the movement axis 7a.
[0100] The slot 81 may have a length, as calculated along the axis 7a, at least equal to
the maximum value of the machine stop distance so that the stop 83 is able to slide
therein along the movement axis 7a over a length substantially equal to the maximum
value of the machine stop distance.
[0101] It may be formed in the side panel 51 or in a plate integral with it.
[0102] Additionally, the limiter 8 may comprise an additional slot 82 integral with the
support frame 34, and more precisely with a wall 341.
[0103] The additional slot 82 has an axis extending substantially parallel to that of the
slot 81.
[0104] The additional slot 82 may have a length, as calculated along the axis 7a, at least
equal to the difference between the maximum and minimum values of the machine stop
distance so that the stop 83 can slide therein along the movement axis 7a over a length
substantially equal to said distance.
[0105] The stop 83 is connected to the control unit so as to be controlled by the same and
thus it places the limiter 8 in the passive or active position based on a command
coming from the control unit as described below.
[0106] It is suitable to place the limiter 8 into the active position by fitting into the
slot 81 and into the passive position by coming out of the slot 81. In particular,
in the active position the stop 83 is inserted in both of the slots 81 and 82 and
in the passive position the stop 83 comes out of the slot 81 and is inserted only
in the additional slot 82.
[0107] The stop 83 comprises a pin
831 suitable to fit into the slots 81 and 82 and a shifter
832 suitable to move the pin 831 with respect to the slots 81 and 82, defining said active
position (Fig. 3a) and passive position (Fig. 3b).
[0108] In the active position, the pin 831 is inserted in both of the slots 81 and 82. In
the passive position, it is not inserted in at least one of the slots 81 and 82 (suitably
it is inserted only in the additional slot 82).
[0109] The shifter 832 is suitable to move the pin 831 along a translation axis 83a substantially
perpendicular to the movement axis 7a, and in particular substantially parallel to
the rotation axis 2a.
[0110] The stop 83 may comprise an anchor plate
833 for anchorage to the wall 341 through constraining means, which are releasable, or
in detail resolvable and define a passage hole for the pin 831.
[0111] The anchor plate 833 can thus have screws or bolts.
[0112] Said passage hole is substantially shaped against the pin 831, and in particular
the shifter 832.
[0113] Moreover, the limiter 8 may comprise a regulator
84 adapted to enable adjustment, suitably in a continuous manner, of the machine stop
distance between a minimum value, greater than the working distance, and a maximum
value, smaller than the maintenance distance.
[0114] The maximum value is substantially less than 10% of the maintenance distance. It
is substantially less than 5 cm, and in detail less than 3 cm. More in detail, it
is substantially equal to 2.5 cm.
[0115] The minimum value of the machine stop distance is at least less than 15 times the
working distance. It is substantially less than 1 cm, and in detail less than 0.5
cm, and more in detail less than 0.2 cm, and conveniently equal to 0.1 mm. Preferably,
the machine stop distance has a minimum value at least equal to 0.1 mm and a maximum
value of less than 5 cm.
[0116] To adjust the machine stop distance, the regulator 84 is suitable to vary the position
of anchorage of the stop 83 to the laying block 3, and in particular to move the stop
83 along the movement axis 7a by adjusting the position of the stop 83 with respect
to the slots 81 and 82, and in particular to the additional slot 82.
[0117] The regulator 84 may comprise, at each of the resolvable constraining means of the
anchor plate 833, an adjustment slot extending substantially parallel to the movement
axis 7a, i.e. to the slots 81 and 82.
[0118] Said adjustment slots are suitable to adjust the machine stop distance on the basis
of the position of the passage hole and therefore of the pin 831 with respect to the
additional slot 82, by modifying the stroke of the pin 831 in the slot 81.
[0119] In particular, the operator constrains the stop 83 so that the pin 831 is at the
end of the additional slot 82 distal to the cylinder 2, and so as to have the minimum
value of the machine stop distance. On the contrary, if the maximum value of the machine
stop distance is required, the operator places the pin 831 at the end of the additional
slot 82 proximal to the contrast cylinder 2. Finally, for any intermediate value of
the machine stop distance, the operator places the stop 83, and in particular the
pin 831, in an intermediate position between those described above.
[0120] Finally, alternatively or additionally, it should be stressed that the regulator
84 can vary the position of at least one of the slots 81 and 82 by changing the extension
of the overlapping portions of the slots 81 and 82.
[0121] Lastly, the deposit group 1 may comprise at least one monitoring station 9 for monitoring
at least one sheet 1 a, 1b and 1 c, and in detail at least the raw sheet 1 a along
the sliding path.
[0122] The monitoring station 9 is suitable to detect an error in the sliding of at least
one of the sheets 1 a, 1 b and/or 1 c and, according to it, command the transition
to the stop configuration in which the mover 7 does not exert the maintenance force,
thereby defining a stop configuration for the deposit group 1 and, advantageously,
the limiter 8 is in the passive position.
[0123] The sliding error can identify an error due to non-feeding and/or absence of at least
one sheet 1 a, 1 b and/or 1 c. In the first case, the sliding error may be due to
a sheet jam, and the monitoring station 9, by detecting its presence but not its feed,
sends a sliding error signal. In the second case, the monitoring station 9 sends a
sliding error signal if it detects the absence of at least one sheet for example due
to a breakage thereof.
[0124] Another possible sliding error, precisely in the case of a multilayer sheet 1 a,
1b and/or 1 c, is the breakage of only some of the layers which, by not sliding any
more along the sliding path, accumulate causing spacing between two components of
the group 1 (in detail between the contrast cylinder 2 and the deposit roller 33 and/or
between the walls 341 and the side panels 51) detected by the station 9. It is pointed
out that the monitoring station 9 can detect distance variations of the order of tenths
of mm.
[0125] The monitoring station 9 monitors the passage of the sheet at a point/area of the
sliding path, detecting an error in the sliding of at least one of the sheets 1 a,
1b and/or 1 c and/or an undesired variation of the distance between the components
of the group 1. It may comprise one or more of an optical/magnetic sensor and a camera.
[0126] The monitoring station 9 is in data connection with the control unit so as to send
said sliding error to said unit and therefore command the transition of the deposit
group 1 to the stop configuration.
[0127] In the stop configuration, the mover 7 is ordered not to exert the aforesaid maintenance
force, the limiter 8 is arranged in the passive position and, suitably, the feeding
of the sheets along the sliding path is stopped.
[0128] In this stop configuration, the mover 7 does not lock the deposit group 1 in the
working configuration and allows a mutual spacing between the laying block 3 and the
contrast cylinder 2, and in particular a distancing of the laying block 3 from the
contrast cylinder 2 at a distance greater than the working distance. In detail, as
the limiter 8 is in the passive position, the distancing of the laying block 3 from
the contrast cylinder 2 can define a distance equal to the maintenance distance.
[0129] The monitoring station 9 can order the discharge of the mover 7, allowing an idle
distancing of the block 3. The mover 7 does not exert any force on the laying block
3 which is free to translate along the movement axis 7a and, as it is lifted from
the ground, can move away from the contrast cylinder 2 as a result of any force external
to the group, such as that of the operator and/or of the pressure of the sheets on
the contrast cylinder 2 or on another component of the group 1.
[0130] Alternatively, the monitoring station 9 can order the mover 7 to reverse its action
and to exert a force for moving the laying block 3 away from the contrast cylinder
2. Preferably, the monitoring station 9 can order the mover 7 to place the group 1
into the maintenance configuration.
[0131] To control the sliding of the processed sheet 1 b, the deposit group 1 may comprise
a monitoring station 9 located downstream of the contrast cylinder 2.
[0132] To monitor the sliding of the raw sheet 1a, the deposit group 1 may comprise a monitoring
station 9 located upstream of the contrast cylinder 2, and in particular of the corresponding
pressure cylinder 61.
[0133] To check the sliding of the additional sheet 1c, the deposit group 1 may comprise
a monitoring station 9 upstream of the slide cylinder 4.
[0134] Advantageously, the deposit group 1 can check the sliding of all the sheets 1a, 1b
and 1c and thus may comprise the aforementioned three monitoring stations 9.
[0135] In addition to or replacement of one or more of said three stations 9, the deposit
group 1 may comprise a monitoring station 9 adapted to measure a change in distance
between the contrast cylinder 2 and the block 3 and available at the contrast cylinder
2; and/or a monitoring station 9 adapted to measure a change in distance between the
rollers 33 and 32 and suitably located in the area of the deposit roller 33.
[0136] The operation of the deposit group, described above as regards structure, is described
below.
[0137] Initially, the group 1 is in the maintenance configuration (Fig. 2a) and the stop
83 is in the passive position (Fig. 3b).
[0138] The operator, by exploiting the regulator 84, constrains the stop 83 to the wall
341, placing the pin 831 into a position relative to the additional slot 82 such that,
with the limiter 8 in the active position, there is a certain machine stop distance.
[0139] Once the adjustment of the machine stop is completed, the operator orders the transition
to the working configuration (Fig. 2b) and arranges the stop 83 into the active position
(Fig. 3a).
[0140] In particular, the operator, thanks to the mover 7, brings the laying block 3 close
to the contrast cylinder 2, superimposing the additional slot 82 and the pin 831 onto
the slot 81, and commands the insertion of the pin 831 in both of the slots 81 and
82.
[0141] At this point, it orders the transition of the deposit group 1 to the stationary
machine configuration (Fig. 2c).
[0142] In particular, the actuator 71 extends, moving the laying block 3 away from the contrast
cylinder 2. The pin 831 slides in the slot 81 and, by abutting against the end of
the slot 81 distal to the contrast cylinder 2, blocks the extension of the actuator
71, thereby preventing a further advance of the laying block 3 and the reaching of
the maintenance configuration.
[0143] The deposit group 1 is in the stationary machine configuration (Fig. 2c).
[0144] At the beginning of the processing of the sheets 1a and 1c, the operator orders the
deposit group 1 to pass into the working configuration (Fig. 2b).
[0145] The sheets 1a and 1c slide and simultaneously the mover 7 brings the deposit roller
33 close to the contrast cylinder 2, allowing the deposit of the liquid on the raw
sheet 1a.
[0146] The transition to the working configuration brings the pin 831 close to the end of
the slot 81 proximal to the contrast cylinder 2.
[0147] The operator, when performing maintenance, brings the limiter 8 into the passive
position (Fig. 3b) causing the pin 831 to come out of the slot 81 so that it is only
inserted in the additional slot 82.
[0148] At this point, the operator orders the transition of the group to the maintenance
configuration (Fig. 2a).
[0149] The transition to the passive position causes the mover 7, since its stroke is not
limited by limiter 8, to fully extend and place the laying block 3 at the maintenance
distance from the contrast cylinder 2.
[0150] Lastly, if one or more of monitoring stations 9 does/do not detect the passage of
the sheet 1b 1a and/or 1c or the breaking of one or more of the layers of the sheet
1a, it/they sends/send a sliding error signal to the control unit. In response to
the signal, the control unit commands the transition to the stop configuration, and
in particular it orders the mover 7 to stop the maintenance force and the stop 83
to pass into the passive position.
[0151] The invention provides significant advantages.
[0152] A first advantage is the presence of the monitoring station 9 which, by detecting
an incorrect paper flow, blocks the group, thereby preventing breakdowns thanks to
the cessation of the maintenance force that moves the block 3 away from the contrast
cylinder 2, avoiding accumulations.
[0153] This aspect brings the deposit block 3 close to the contrast cylinder 2 in complete
safety, minimizing the machine stop distance, by adjusting it to the thickness of
the sheet being processed, and therefore the transition time from the stationary machine
configuration to the working configuration.
[0154] Another advantage is that the deposit group 1 reduces the ratio of liquid-free sheets,
thus avoiding waste from production by distributors.
[0155] A non-secondary advantage is that, in the maintenance configuration, the laying block
3, compared to the known groups, has an increased distance from the contrast cylinder
2, thus ensuring a large operating/intervention space.
[0156] Another advantage is that the deposit group 1, being fully anchored to the support
structure 5, is transportable already assembled.
[0157] The invention is susceptible of variations falling within the scope of the inventive
concept, as specified in the independent claims, and of the related technical equivalents.
In this context, all details are replaceable by equivalent elements and any type of
materials, shapes and dimensions may be present.