Technical field
[0001] The present invention relates to systems for stacking sheets, for example sheets
of corrugated cardboard or the like.
[0002] The invention also relates to a method for forming stacks or piles of sheets, in
particular although not exclusively sheets of corrugated cardboard, fed continuously
from a production line.
Prior art
[0003] The production of corrugated cardboard takes place by means of lines which operate
continuously. Continuous webs of cardboard fed from reels being unwound are joined
together, with a corrugated web interposed between two smooth sheets or webs, called
facings. For technical reasons, the production of corrugated cardboard takes place
at an essentially constant speed. A continuous web of corrugated cardboard is then
scored and cut longitudinally into strips of the desired width corresponding to the
width of the finished sheets to be obtained upon delivery from the production line.
Each strip is also divided crosswise to obtain the individual sheets which are fed
essentially continuously to the so-called stacker.
[0004] This section of the production line includes a first area, wherein the sheets are
partly overlapped with one another, i.e. disposed with a shingled arrangement. The
sheets thus arranged are fed along a series of conveyors, which can have a variable
feed speed, to a collection table. This collection table is gradually lowered as the
stack or pile of sheets forms thereon. Once the desired number of sheets has been
reached on the single pile or stack, the latter must be moved away to free the table
on which the subsequent stack forms.
[0005] This operation to remove the stack formed must not influence the feed speed of the
web of corrugated cardboard and, consequently, the production speed of individual
sheets. Therefore, in order to produce a temporary interruption in the flow of sheets
reaching the stacking area, the speed of advance of the individual conveyor belts
extending from the shingling area of the sheets to the stacking area is modified in
a controlled way. The last sheets to be collected on a stack being completed are moved
away from the sheets destined to form the start of the subsequent pile or stack due
to the difference in speed of the sheets along the path defined by the conveyors.
The sheets which slow down to produce this interruption in the flow are overlapped
with one another to a greater extent, so that the same quantity of sheets per unit
of time are essentially fed to the stacker, while at the exit side of the first section
of the stacker (where the sheets are disposed in a shingled arrangement) towards the
conveyors which convey the sheets to the stacking area, the sheets are slowed down
and overlapped with one another to a greater extent. This transient phase ceases when
the stack or pile formed has been removed and the stacking table has been returned
to the correct height to receive the first sheets of the subsequent stack.
[0006] Various systems have been produced to perform these operations, differing for example
in the sequence of speeds set on the conveyors, in the means to retain the sheets,
in the variation in the degree of shingling of sheets and in other specific characteristics
known to those skilled in the art.
[0007] For example,
US-A-5,415,389 describes a system in which the sheets destined to form the new pile or stack are
slowed down and lifted from the conveyor below by means of a gripper which travels
along the feed path of the sheets. For this purpose, the gripper is mounted on a carriage
or slide controlled with an alternate movement. A further system which uses a movable
gripper to control sheets is described in
US-A-5,829,951.
[0008] US-A-4,200,276 describes a different sheet shingling and stacking system.
[0009] US-A-4,313,600 describes a stacker in which the series of sheets destined to form a new pile is
temporarily slowed down and controlled by a chain conveyor device which raises the
sheets making them advance more slowly with respect to the feed speed of the conveyor
belt below, which finishes feeding the last sheets to the nearly completed pile.
[0010] EP-A-0427324 describes another stacker in which variable speeds of conveyors in line allow the
gap in the flow of sheets during the transient phase to complete a pile and start
forming the subsequent pile.
[0011] US-A-4,273,325 describes a stacker for sheets of corrugated cardboard characterized by a particular
arrangement of the members to control the sheets unloaded from the series of conveyor
belts onto the pile being formed.
[0012] US-A-4,598,901 describes a stacker characterized by a particular arrangement of the members which
perform shingling of the sheets, i.e., which positions them in a partially overlapped
arrangement to feed them on the series of conveyors that unload the sheets onto the
pile.
[0013] A further example of a device to perform shingling of sheets is described in
US-A-4,776,577.
[0014] Further examples of stackers are described in
US-A-4,188,861;
DE-AS-1148437;
EP-A-0802025;
US-A-3,834,288;
US-A-4,040,618;
US-A-3,938,674;
US-A-3,995,540;
US-A-4,133,523.
[0015] The type of speed sequence and of mechanisms used to obtain the variation in shingling
of the sheets during the transient phase to remove a pile or stack and start forming
the subsequent stack does not represent a specific aspect of the present invention,
as said invention can be applied to any type of stacker in which a variation in the
degree of shingling in the transient phase is required.
[0016] To obtain correct stacking of the sheets, preventing slippage of said sheets when
they are unloaded from the conveyor belts onto the pile or stack being formed, owing
for example to the cushion of air forming between the upper surface of the stack and
the lower surface of the sheet being unloaded onto said stack, it is necessary for
sheets unloaded from the last conveyor belt onto the pile being formed to have a specific
angle with respect to the horizontal, i.e. with respect to the upper surface of the
pile. For this purpose the unloading angle of the last conveyor belt is chosen specifically,
to unload the sheets correctly onto the pile or stack.
[0017] Nonetheless, once the unloading angle of the last conveyor of the stacker has been
set, the effective angle of incidence with which the sheet is unloaded onto the pile
being formed also depends on the degree of shingling, i.e. on the greater or lesser
reciprocal overlapping of the sheets on the conveyors. This means that in the transient
phase in which sheets are overlapped to a greater extent with one another on the feed
path to the stacking area, the angle of incidence with which the sheets are unloaded
on the pile no longer coincides with the optimal angle chosen when designing the stacker
and defined by the inclination of the final section of the last conveyor belt.
[0018] Consequently, there is a risk of slippage of the sheets at least in the initial transient
phase to form a pile or stack.
[0019] WO-A-8810227 discloses a stacker according to the preamble of claim 1, wherein the last conveyor
has an inclination which is adjustable as a function of the operating conditions of
the device, to reduce the variation of the angle of incidence of the sheets with respect
to the stacking table when the operating conditions vary.
Objects and summary of the invention
[0020] The object of the present invention is to produce a stacking device, which eliminates
or at least reduces the aforesaid drawbacks and makes stacking of the sheets more
uniform even in the transient phases, when the degree of overlapping, i.e. of shingling
of the sheets, varies with respect to the condition of overlapping at normal operating
speed.
[0021] This and further objects and advantages, which will be apparent to those skilled
in the art from reading the text hereunder, are in substance obtained with a device
according to claim 1. The dependent claim relate to advantageous further developments
of the invention.
[0022] In practice, with a device of this type it is possible to modify the arrangement,
i.e. the position, of the end section of the last conveyor so that the angle of incidence
of the sheets which are unloaded onto the pile being formed by said conveyor does
not undergo excessive variations with respect to an optimal angle when there is a
variation in the operating conditions of the stacking system, and in particular when
there is a variation in the degree of shingling, i.e. overlapping, of the individual
sheets.
[0023] In substance, according to the invention the stacker is designed so that the conveyor
has an optimal form and position for unloading of the sheets with the chosen angle
of incidence in normal operating conditions. When, on the other hand, during the transient
phase to remove the completed pile, it is necessary to produce a gap in the flow of
sheets on the series of conveyors, with a consequent increase in the degree of reciprocal
overlapping of the sheets, the invention allows the configuration of the last conveyor
to be adjusted to correct - by reducing it - the variation of the angle of incidence
with which the sheets are unloaded onto the pile due to this varied condition of reciprocal
overlapping of the sheets. The correction can be made continuously as a function of
the degree of overlapping of the sheets, or two or more predetermined positions can
be provided as a function of the degree of overlapping, with stepped adjustment.
[0024] Using one of the known systems to check the flow of sheets by means of variation
of the degree of shingling and variation of the feed speed of the individual conveyors,
the control unit of the stacker can know, at all times, the degree of overlapping
of the sheets in the unloading area from the last conveyor onto the pile being formed.
With this information it is possible to control the arrangement of the final conveyor,
i.e. the unloading conveyor. Alternatively, it would also be possible to provide sensor
means, such as optical sensors, which detect the position of the sheets (in particular
the thickness of the sheets which varies with the degree of shingling) in the unloading
area from the conveyor, with control of the arrangement of the last conveyor on the
basis of the signals coming from these sensors.
[0025] According to a possible embodiment of the invention, the last conveyor includes,
in a way known per se, a continuous flexible member (such as a belt) sliding on a
supporting surface. According to the invention the supporting surface, which can be
produced with an elastically deformable plate, has a variable conformation to modify
the configuration of said flexible member.
[0026] Advantageously, to maintain control of the belt or other flexible member, a guide
channel can be provided on the supporting surface, inside which said flexible member
engages, for example by means of a longitudinal projection or edge. To maintain flexibility
and, consequently, the capacity for elastic deformation of the supporting surface,
the guide channel can be produced in an area of the sheet forming the supporting surface
which is provided with a series of slots aligned along the direction of advance of
the flexible member. These slots allow the plate to deform elastically notwithstanding
the presence of bends to form the channel.
[0027] To obtain deformation of the plate or other mechanical element forming the supporting
surface for the flexible member forming the last conveyor of the stacker, it is advantageous
to provide a movable support which acts on the deformable supporting surface on the
opposite face from the one on which the flexible member slides. The movable support
can include a series of elongated elements according to the direction of advance of
the flexible member. These elongated elements can be integral with one another so
that a single actuator can control the movement of all the elongated elements, although
it would also be possible to use elements separate from one another. The movable support
advantageously has a curved supporting surface against which, as a consequence of
lifting of the support, the supporting and sliding surface of the flexible member
of the conveyor is deformed.
[0028] According to an advantageous embodiment of the invention, the movable support can
be oscillating about a transverse axis with respect to the direction of advance of
the flexible member. Advantageously, for improved control of the angle at which the
sheets are delivered from the last conveyor of the stacker, the axis of oscillation
of the movable support is placed in close proximity to, or coinciding with, the axis
of rotation of a delivery roller of the sheets, disposed downstream of the last conveyor
with respect to the direction of advance of said sheets.
[0029] Further and advantageous characteristics and embodiments of the device according
to the invention are indicated in the appended claims and will be better described
with reference to a particularly advantageous and currently preferred embodiment of
the invention.
Brief description of the drawings
[0030] The invention shall be better understood by following the description and accompanying
drawing, which shows non-limiting examples of embodiments of the invention. More specifically,
in the drawing:
Figures 1A and 1B show a side view of a stacker to which the invention is applied;
Figures 2 and 3 show the end portion of the last conveyor and the area for unloading
the sheets and forming the pile or stack, in two different arrangements of the conveyor;
Figure 4 shows a plan view according to IV-IV in Figure 3;
Figure 5 shows a local section according to V-V in Figure 3;
Figure 6 shows an enlarged detail of the part indicated with VI in Figure 2.
Detailed description of a preferred embodiment of the invention
[0031] Figure 1 shows in a side view a stacker, indicated as a whole with 1, to which the
present invention is applied. As a whole the stacker 1 is produced according to the
description in
US patent no. 5,415,389, which can be referred to for greater details of operation thereof, and therefore
is not described in detail herein.
[0032] The stacker 1 has an inlet section 3, in which sheets F of corrugated cardboard,
coming from a forming line, not shown, are partially overlapped with one another with
a degree of overlapping (shingling) which can vary during the forming cycle of an
individual pile of sheets. The inlet section has a conveyor 5 operated by a geared
motor 7. Disposed downstream of the conveyor 5 is a series of further conveyors 9,
11 and 13, each of which includes, for example, a belt or other continuous flexible
member. The conveyors 9, 11 and 13 are operated by respective geared motors 15, 17
and 19. Associated with the conveyor 9 is a carriage 21, mounted on which is a gripper
23, operated by a piston-cylinder actuator 25, which engages the first sheets of a
series of sheets F destined to form a new pile in the stacking area.
[0033] Operation of the gripper 23 and of the conveyors 5, 9, 11 and 13 is described in
the aforesaid
US patent no. 5,415,389 and will not be described herein in greater detail. It suffice to mention that the
individual sheets are fed to the section 3 at an essentially constant speed, while
upon delivery from the last conveyor 13 there must be intervals of time during which
no sheet is unloaded, to allow removal of a formed pile and repositioning of the storage
table at the correct height to start stacking the first sheets of a subsequent pile.
In fact, the stacking station, indicated as a whole with 31, is provided with a table
33 movable vertically according to the double arrow f33 along vertical guides 37.
The stacking table 33 must be at a distance that allows the sheets coming from the
last conveyor 13 to accumulate thereon correctly, being stopped by a stop 39 which
is adjustable according to the double arrow f39 as a function of the longitudinal
dimension of the sheets F. Therefore, as the pile forms the table 33 is lowered gradually.
[0034] When a pile has been completed on the table 33 and it is in the lower position thereof,
the pile must be removed and the table 33 returned to the height to start forming
the subsequent pile. This operation requires some seconds during which flow of the
sheets F is interrupted on the series of conveyors 9, 11 and 13. This gap is also
obtained by increasing the degree of reciprocal overlapping of the first sheets destined
for the new pile or stack being formed and with this increasing the overall thickness
of the sheets laid on the conveyors 5 - 13.
[0035] Figure 2 shows the end portion of the last conveyor 13, on which sheets F are overlapped
to a greater extent, typical of the transient phase which follows unloading of a completed
pile P. As can be seen in Figure 2, the first sheet F1 which is unloaded from the
conveyor 13 onto the horizontal surface defined by the sheet F2 previously unloaded
on the pile being formed is not optimal: the sheet F is inclined upwards thereby favoring
"floating" of said sheet on the cushion of air which forms between the sheets F1 and
F2. This cushion of air causes the risk of the sheet F1 slipping to the side and consequently,
of an untidy pile being formed of sheets which are not perfectly aligned. This phenomenon
is not controlled adequately even if brushes 40 (know per se) are provided to push
the sheets F1, unloaded in sequence from the conveyor 13, downwards.
[0036] To avoid the phenomenon of slippage of the sheets, the correct position in which
the sheets F must be unloaded from the conveyor 13 is the one illustrated in Figure
3, with the first sheet F1 horizontal or preferably inclined downwards with a slight
inclination in the order of 4° with respect to the horizontal. In substance, the front
edge of the sheet F1 points downwards. This greatly reduces the tendency of the sheet
F1 to "float" on the cushion of air which can form between the sheets F1 and F2. On
the other hand, in normal operating conditions, i.e. outside the transient phase to
unload a formed pile and start forming the subsequent pile, the arrangement of the
conveyor 13 represented in Figure 3 would lead to an excessively high angle of incidence
of the sheet F1. This is because in normal operating conditions, distant from the
transient phases, the sheets F disposed on the conveyor 13 are overlapped with one
another to a much lesser degree and therefore the overall thickness of the sheets
disposed on the conveyor is inferior. The optimal arrangement of the conveyor 13 in
operating conditions outside the transient phase is the one shown in Figure 2.
[0037] The invention provides for modifcation of the configuration of the end part of the
conveyor 13 from the arrangement in Figure 2 to the arrangement in Figure 3 and vice
versa as a function of the operating conditions of the stacker 1. In practice, in
the transient phases the conveyor 13 will have the configuration in Figure 3, while
in the normal operating phases said conveyor will have the configuration in Figure
2.
[0038] The members to modify the arrangement, i.e. the conformation of the end portion of
the conveyor 13 will be described in greater detail hereunder with reference in particular
to Figures 2 to 6.
[0039] In practice, the conveyor 13 includes a continuous flexible member, typically a belt
41, driven around a motorized end roller 43, and around an idle roller 44 (Figure
1) disposed upstream. The upper section of the conveyor strip or belt 41 is guided
on supporting and sliding surfaces formed by suitably shaped plates. The last of these
supporting surfaces is formed in part by a plate 45, the form and position of which
is modified according to the operating conditions of the stacker 1 to pass from the
arrangement in Figure 2 to the arrangement in Figure 3 and vice versa.
[0040] The plate 45 is fastened with the back edge 45A thereof to a fixed transverse crosspiece
47, integral with the load-bearing structure 49, which is also provided with sides
51 to contain the sheets F. The front edge 45B of the plate 45 is connected, by means
of an arrangement of brackets 45C (Figure 6), pins 45D and slots 51, to elongated
supporting elements 53. These elongated elements (see also Figure 4) extend in the
direction of movement of the conveyor 13 and have free ends 53A oriented towards the
area from which the sheets F are fed. The individual elements 53 are connected to
one another by means of a first crosspiece 55 and a second crosspiece 57, so as to
form a single support for the plate 45. The support formed of the elongated elements
53 and of the crosspieces 55, 57 is hinged about the axis A-A of rotation of a roller
59 to unload the sheets onto the table 33 on which the pile of sheets P forms. The
support 53, 55, 57 oscillates about the axis A-A controlled by a piston-cylinder actuator
61, the rod of which is hinged in 63 to the support and in 65 to the fixed structure
49.
[0041] The elongated elements 53 have a curved profile with the convexity facing upward,
forming a curved supporting surface for the plate 45. Consequently, as can be seen
by comparing Figures 2 and 3, by raising the support 53, 55, 57 with an oscillating
movement in a clockwise direction about the axis A-A, the extrados (i.e. the convex
surface) of the elongated elements 53 presses against the lower surface of the plate
45 to cause bending, i.e. an upward curvature. Coupling by means of pin and slot (51,
45C, 45D) with the backlash that this allows, facilitates deformation of the plate
45.
[0042] In an alternate position with respect to the elongated elements 53, integral with
the fixed structure 49 are elongated section bars 67, forming fixed supports for the
plate 45. The fixed supports 67 are carried by the crosspiece 47 and by a further
crosspiece 69.
[0043] The final section of the upper branch of the conveyor 13 is supported, downstream
of the front edge 45B of the plate with variable arrangement 45, by a further supporting
plate 71, preferably flat, connected rigidly to the elongated elements 53 and to the
crosspiece 57. While the plate 45 is arched, i.e. deformed as a consequence of raising
of the supports 53 when the conveyor 13 changes from the arrangement in Figure 2 to
the arrangement in Figure 3, the plate downstream 71 remains essentially flat, with
modification only of the angle with respect to the horizontal. Inclination of the
plate 71 defines the unloading angle of the sheets F from the conveyor 13 onto the
table for storage and formation of the pile P.
[0044] The motorized drive roller 43 of the strip or belt 41 is supported by the arched
end supporting elements 53, i.e. the outermost ones, so as to move therewith under
the thrust of the piston-cylinder actuator 61. The geared motor 19 is, on the other
hand, supported by the fixed structure 49. Motion is transmitted (see Figure 4) by
means of a constant velocity joint 20. The roller 59 for unloading or delivery of
the sheets from the conveyor 13 is made to rotate by means of the same geared motor
19 through a chain drive 60 and remains fixed in space when the supports 53 oscillate,
changing from the arrangement in Figure 2 to the arrangement in Figure 3 or vice versa,
as this movement is a movement of oscillation about the axis A-A of said roller.
[0045] Also represented in Figures 2 and 3 are an upper idle roller 81 which rests, oscillating
about an axis B, on the upper surface of the assembly of sheets F fed from the conveyor
13. The brush 40 is associated with the oscillating arm (indicated with 82) which
supports the idle roller 81.
[0046] To guide the belt 41 along the surface formed by the plate 45 and by the plate 71,
the-belt-has longitudinal projections, one of which is indicated schematically with
41A in Figure 5. The two projections, which are in proximity to the longitudinal edges
of the belt 41, are guided in corresponding channels 45E and 71E formed by the plate
45 and by the plate 71, which for this purpose are suitably folded along longitudinal
folding lines. To maintain the flexibility of the plate 45 it has a series of slots
produced aligned with one another at the level of the channels 45E, which are in practice
formed of sections of folded plate separated from one another by empty spaces.
[0047] It is understood that the drawing shows one an example provided purely as a practical
embodiment of the invention, which may vary in shapes and arrangements without however
departing from the scope of the claims. Any reference numbers in the appended claims
are provided for the purpose of facilitating the reading thereof, with reference to
the description and to the drawing and do not limit the scope of protection represented
by the claims.
1. A device for stacking sheets of cardboard or the like, including:
- an inlet section (3), in which the sheets are fed and disposed in a shingled arrangement,
with a variable reciprocal degree of overlapping;
- a stacking station (31), in which predetermined quantities of sheets are stacked
on a collection table (33) to form piles of sheets;
a series of conveyors (9, 11, 13) to convey the sheets from said inlet section to
said stacking station; wherein at least the unloading end of the last conveyor (13)
of said series has an inclination adjustable as a function of the operating conditions
of the device, to reduce the variation of the angle of incidence of the sheets with
respect to the stacking table (33) when said operating conditions vary;
characterized in that said last conveyor (13) includes a continuous flexible member (41), sliding on a
supporting surface (45), said supporting surface (45) having a variable conformation
to modify the configuration of said flexible member (41).
2. Device as claimed in claim 1, characterized in that it includes a control unit, programmed to regulate said inclination as a function
of the degree of shingling of the sheets being fed along said series of conveyors.
3. Device as claimed in claim 1 or 2, characterized in that said supporting surface (45) is formed by an elastically deformable plate.
4. Device as claimed in claim 1, 2 or 3, characterized in that said supporting surface (45) includes at least a guide channel (45E) for said flexible
member (41).
5. Device as claimed in claim 4, characterized in that said supporting surface (45) is formed by a folded plate to define said guide channel
(45E) which has a plurality of slots aligned along the direction of advance of said
sheets, to maintain the flexibility of said plate.
6. Device as claimed in one or more of to the preceding claims, characterized in that disposed under said supporting surface (45) with variable conformation is a movable
support, which acts on said surface from the opposite side to the side on which said
flexible (41) member slides.
7. Device as claimed in claim 6, characterized in that said movable support includes a series of elongated elements (53), oriented according
to the direction of advance of said flexible member (41).
8. Device as claimed in claim 7, characterized in that said elongated elements (53) are integral with one another.
9. Device as claimed in one or more of claims 6 to 8, characterized in that said movable support has a curved supporting surface, against which the sliding surface
of the flexible member (41) of the conveyor is deformed.
10. Device as claimed in one or more of claims 6 to 9, characterized in that said movable support oscillates about an axis (A-A) transverse with respect to the
direction of advance of said flexible member.
11. Device as claimed in claim 10, characterized in that said support oscillates about an axis (A-A) of rotation of a delivery roller (59)
of the sheets, disposed downstream of the last conveyor (13) with respect to the direction
of advance of the sheets.
12. Device as claimed in one or more of claims 6 to 11, characterized in that said movable support is controlled by an actuator (61).
13. Device as claimed in one or more of claims 6 to 12, characterized in that a first end (45A) of said surface is fastened to a fixed structure (47) supporting
said conveyors and a second end (45B) is connected to said movable support.
14. Device as claimed in claim 13, characterized in that a connection is provided between the second end (45B) of said surface (45) and said
movable support to allow a relative movement between said movable support and said
end (45B).
15. Device as claimed in one or more of claims 6 to 14, characterized in that said movable support is integral with another supporting surface (71) with variable
inclination, forming a continuation of the supporting surface (45) with variable conformation.
16. Device as claimed in claim 15, characterized in that said further supporting surfaces (71) is a flat surface.
17. Device as claimed in one or more of the previous claims, characterized in that said inclination is controlled so as to take a plurality of discrete values as a
function of the operating conditions of the device.
18. Device as claimed in one or more of the previous claims, characterized in that said inclination is controlled to be modified continuously as a function of said
operating conditions, maintaining the angle of incidence of the sheets with respect
to the stacking table (33) essentially constant.
1. Vorrichtung zum Stapeln von Bogen aus Wellpappe oder dergleichen mit
- einem Einlassabschnitt (3), in welchen die Bogen eingeführt und in einer geschuppten
Anordnung mit einem variablen Ausmaß der Überlappung angeordnet werden;
- eine Stapelstation (31), in welcher vorgegebene Mengen an Bogen auf einem Sammeltisch
(33) zur Bildung von Bogenpaketen gestapelt werden;
- eine Reihe von Förderern (9, 11, 13), um die Bogen von dem Einlassabschnitt zur
Stapelstation zu fördern; wobei wenigstens das Ausgabeende des letzten Förderers (13)
der Reihe eine Neigung hat, die als Funktion der Betriebsbedingungen der Vorrichtung
einstellbar ist, um die Veränderung des Einfallswinkels der Bogen bezüglich des Stapeltisches
(33) zu reduzieren, wenn die Operationsbedingungen sich ändern;
dadurch gekennzeichnet, dass der letzte Förderer (13) ein endloses flexibles Bauteil (41) aufweist, welches auf
einer Lagerfläche (45) gleitet, wobei die Lagerfläche (45) eine variable Ausbildung
besitzt, um die Konfiguration des flexiblen Bauteils (41) zu modifizieren.
2. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass sie eine Steuereinheit aufweist, die zur Steuerung der Neigung als eine Funktion
des Ausmaßes der Schuppung der Bogen, die längs der Reihe von Förderern angeliefert
werden, programmiert ist.
3. Vorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass die Lagerfläche (45) durch eine elastisch deformierbare Platte gebildet ist.
4. Vorrichtung nach Anspruch 1, 2 oder 3, dadurch gekennzeichnet, dass die Lagerfläche (45) wenigstens einen Führungskanal (45E) für das flexible Bauteil
(41) aufweist.
5. Vorrichtung nach Anspruch 4, dadurch gekennzeichnet, dass die Lagerfläche (45) durch eine gefaltete Platte gebildet ist, um den Führungskanal
(45E) zu definieren, welcher mehrere Schlitze aufweist, die längs der Vorschubrichtung
der Bogen ausgerichtet sind, um die Flexibilität der Platte aufrecht zu erhalten.
6. Vorrichtung nach einem oder mehreren der vorstehenden Ansprüche, dadurch gekennzeichnet, dass unterhalb der Lagerfläche (45) mit variabler Ausbildung ein beweglicher Support angeordnet
ist, der auf die Fläche von der gegenüber liegenden Seite zu derjenigen Seite, auf
welcher das flexible Bauteil (41) gleitet, einwirkt.
7. Vorrichtung nach Anspruch 6, dadurch gekennzeichnet, dass der bewegliche Support eine Reihe von langgestreckten Elementen (53) aufweist, die
entsprechend der Vorschubrichtung des flexiblen Bauteils (41) orientiert sind.
8. Vorrichtung nach Anspruch 7, dadurch gekennzeichnet, dass die langgestreckten Elemente (53) miteinander integral sind.
9. Vorrichtung nach einem oder mehreren der Ansprüche 6-8, dadurch gekennzeichnet, dass der bewegliche Support eine gebogene Supportfläche aufweist, gegen welche die Gleitfläche
des flexiblen Bauteils (41) des Förderers deformiert ist.
10. Vorrichtung nach einem oder mehreren der Ansprüche 6-9, dadurch gekennzeichnet, dass der bewegliche Support um eine Achse (A-A) oszilliert, die bezüglich der Vorschubrichtung
des flexiblen Bauteils sich quer erstreckt.
11. Vorrichtung nach Anspruch 10, dadurch gekennzeichnet, dass der Support um eine Drehachse (A-A) einer Ausgaberolle (59) der Bogen oszilliert,
die abstromseitig zu dem letzten Förderer (13) bezüglich der Vorschubrichtung der
Bogen angeordnet ist.
12. Vorrichtung nach einem oder mehreren der Ansprüche 6-11, dadurch gekennzeichnet, dass der bewegliche Support durch einen Betätiger (61) gesteuert ist.
13. Vorrichtung nach einem oder mehreren der Ansprüche 6-12, dadurch gekennzeichnet, dass ein erstes Ende (45A) der Fläche an einer festen Struktur (47) befestigt ist, welche
die Förderer hält, und ein zweites Ende (45B) mit dem beweglichen Support verbunden
ist.
14. Vorrichtung nach Anspruch 13, dadurch gekennzeichnet, dass eine Verbindung zwischen dem zweiten Ende (45B) der Fläche (45) und dem beweglichen
Support vorgesehen ist, um eine relative Bewegung zwischen dem beweglichen Support
und dem Ende (45B) zu ermöglichen.
15. Vorrichtung nach einem oder mehreren der Ansprüche 6-14, dadurch gekennzeichnet, dass der bewegliche Support mit einer weiteren Supportfläche (71) mit variabler Neigung
integral ist, die eine Fortsetzung der Supportfläche (45) mit variabler Ausbildung
bildet.
16. Vorrichtung nach Anspruch 15, dadurch gekennzeichnet, dass die weitere Supportfläche (71) eine ebene Fläche ist.
17. Vorrichtung nach einem oder mehreren der vorstehenden Ansprüche, dadurch gekennzeichnet, dass die Neigung derart gesteuert ist, dass sie als Funktion der Betriebsbedingungen der
Vorrichtung mehrere diskrete Werte annimmt.
18. Vorrichtung nach einem oder mehreren der vorstehenden Ansprüche, dadurch gekennzeichnet, dass die Neigung derart gesteuert ist, dass sie als Funktion der Betriebsbedingungen stufenlos
modifiziert werden kann, wobei der Einfallswinkel der Bogen bezüglich des Stapeltisches
(33) im Wesentlichen konstant bleibt.
1. Dispositif pour empiler des feuilles de carton ou analogues, comprenant :
- une section d'entrée (3) dans laquelle les feuilles sont amenées et disposées selon
un agencement superposé avec un degré réciproque variable de chevauchement ;
- un poste d'empilage (31) dans lequel des quantités prédéterminées de feuilles sont
empilées sur une table de collecte (33) pour former des piles de feuilles ;
- une série de transporteurs (9, 11, 13) pour acheminer les feuilles de ladite section
d'entrée audit poste d'empilage, dans lequel au moins l'extrémité de décharge du dernier
transporteur (13) de ladite série a une inclinaison réglable en fonction des conditions
de fonctionnement du dispositif pour réduire la variation de l'angle d'incidence des
feuilles par rapport à la table d'empilage (33) quand lesdites conditions de fonctionnement
varient ;
caractérisé en ce que ledit dernier transporteur (13) comprend un élément flexible continu (41) glissant
sur une surface de support (45), ladite surface de support (45) ayant une conformation
variable pour modifier la configuration dudit élément flexible (41).
2. Dispositif selon la revendication 1, caractérisé en ce qu'il comprend une unité de commande programmée pour réguler ladite inclinaison en fonction
du degré de superposition des feuilles amenées le long desdites séries de transporteurs.
3. Dispositif selon la revendication 1 ou 2, caractérisé en ce que ladite surface de support (45) est formée par une plaque élastiquement déformable.
4. Dispositif selon la revendication 1, 2 ou 3, caractérisé en ce que ladite surface de support (45) comprend au moins un canal de guidage (45E) pour ledit
élément flexible (41).
5. Dispositif selon la revendication 4, caractérisé en ce que ladite surface de support (45) est formée par une plaque pliée pour définir ledit
canal de guidage (45E), qui a une pluralité de fentes alignées le long de la direction
d'avance desdites feuilles, pour maintenir la flexibilité de ladite plaque.
6. Dispositif selon l'une ou plusieurs des revendications précédentes, caractérisé en ce qu'un support mobile est disposé sous ladite surface de support (45) avec une conformation
variable, lequel agit sur ladite surface à partir du côté opposé au côté sur lequel
l'élément flexible (41) coulisse.
7. Dispositif selon la revendication 6, caractérisé en ce que ledit support mobile comprend une série d'éléments allongés (53) orientés selon la
direction d'avance dudit élément flexible (41).
8. Dispositif selon la revendication 7, caractérisé en ce que lesdits éléments allongés (53) sont solidaires les uns des autres.
9. Dispositif selon une ou plusieurs des revendications 6 à 8, caractérisé en ce que ledit support mobile a une surface de support incurvée contre laquelle la surface
glissante de l'élément flexible (41) du transporteur est déformée.
10. Dispositif selon une ou plusieurs des revendications 6 à 9, caractérisé en ce que ledit support mobile oscille autour d'un axe (A-A) transversal par rapport à la direction
d'avance dudit élément flexible.
11. Dispositif selon la revendication 10, caractérisé en ce que ledit support oscille autour d'un axe (A-A) de rotation d'un galet de fourniture
(59) des feuilles, disposé en aval du dernier transporteur (13) par rapport à la direction
d'avance des feuilles.
12. Dispositif selon une ou plusieurs des revendications 6 à 11, caractérisé en ce que ledit support mobile est commandé par un dispositif d'actionnement (61).
13. Dispositif selon une ou plusieurs des revendications 6 à 12, caractérisé en ce qu'une première extrémité (45A) de ladite surface est fixée à une structure fixe (47)
supportant lesdits transporteurs et une deuxième extrémité (45B) est reliée audit
support mobile.
14. Dispositif selon la revendication 13, caractérisé en ce qu'une liaison est prévue entre la deuxième extrémité (45B) de ladite surface (45) et
ledit support mobile pour permettre un mouvement relatif entre ledit support mobile
et ladite extrémité (45B).
15. Dispositif selon une ou plusieurs des revendications 6 à 14, caractérisé en ce que ledit support mobile est solidaire d'une autre surface de support (71) avec une inclinaison
variable formant une continuation de la surface de support (45) avec une conformation
variable.
16. Dispositif selon la revendication 15, caractérisé en ce que ladite autre surface de support (71) est une surface plane.
17. Dispositif selon une ou plusieurs des revendications précédentes, caractérisé en ce que ladite inclinaison est commandée afin d'avoir une pluralité de valeurs distinctes
en fonction des conditions de fonctionnement du dispositif.
18. Dispositif selon une ou plusieurs des revendications précédentes, caractérisé en ce que ladite inclinaison est commandée pour être modifiée de façon continue en fonction
desdites conditions de fonctionnement en maintenant l'angle d'incidence des feuilles
par rapport à la table d'empilage (33) essentiellement constant.