[0001] The present Patent for Industrial Invention relates to an automatic unloading system
at the outlet of machines for producing paper bags or paper and plastic film bags.
[0002] The present automatic unloading system is the missing element in the production lines
of paper bags or also paper bags with a transparent strip; such a system performs
the automatic unloading in "packages" of desired dimensions or number of bags, generally
from 50 to 100 pieces each, automatically, i.e. without the presence of an operator.
Indeed, currently one or also two operators are to be present in line on the bag making
machine to remove the packages of bags produced and then bind them manually or with
manual strapping tools or with simple elastic rings of the traditional type.
[0003] Indeed, starting from the simple general paper tape or with a strip of transparent
plastic film, during the path that starts from the roll of paper to the formed bag,
bag making machines perform a series of processing operations of pre-perforation,
forming the tubular body, and both longitudinal and transverse gluing, up to the complete
production of the finished paper bag, then at the end of the processing path, the
finished bag is stacked according to a horizontal axis on an unloading plane in almost
radial direction with respect to the forming drum of the machine. Proceeding in the
unloading of the bags one after the other against a contrast abutment parallel to
the plane of the bag, a continuous stack of bags arranged orthogonally to the support
plane is formed with the opening of the bags upwards; to allow the successive taking
at the outlet by an operator, at the wanted number of bags, for example, every fifty
bags, the fifty-first, by means of a suitable preset counter, is released by the pliers
of the drum slightly in advance and is unloaded into the stacker, protruding from
the stack itself like a bookmark, the reason for which a characteristic horizontal
stack is formed with said "bookmarks" clearly visible to the operators appointed to
unloading, who remove them in packages equal to the distance between one bookmark
and the next, and equal, like in the example mentioned, to the number of fifty bags
each.
[0004] Since said machines are very fast, also up to productions equal to 800 bags per minute,
it is understood how often a single operator is not capable of dealing with said productions
by completing the binding or in any case a packaging, as required.
[0005] Another element of difficulty in packing the final production of these bags is the
presence in many current productions of long and narrow bags, such as for example
the ones intended for packaging bread such as traditional
baguettes, which are difficult to keep stacked also for very short stacking paths.
[0006] The present system resolves both the noted problem of high production speeds and
of the dimensions of said long bags with a single solution by operating both quickly
and while not undergoing any conditioning due to the length.
[0007] In the current art, there is no machine or equipment on the market intended to grip
packages outcoming from the production line of a bag making machine. The present automatic
unloading system is combined with a traditional bag making machine and in particular,
in the final area, immediately after the outlet drum of the bags, where normally a
plate with wheels with abutment pins is arranged, where the bags just formed are collected.
Applied on said outlet plate is a spreader equipped with two oscillating movements,
a primary one for positioning the whole system and a secondary one for opening two
shaped plates such as to separate the end of one package just produced from the beginning
of the following one, all during the continuous production of the bags outcoming from
the drum. The whole set carrying the spreader is also provided with a vertical movement
for allowing the cycle start repositionings. During the opening of the spreader, pliers
with shaped teeth are inserted into the spreader between two separate packages of
bags, i.e. the flat teeth of the pliers find room between similar alternate teeth
of the spreader so as to seize, from below, the stacked bags with glued bottom downwards.
Once a pre-counted package of bags is seized, the pliers begin spacing themselves
apart from the new package being formed by moving towards the outlet of the machine
with the pliers upwards, i.e. in the same direction towards which they were detached.
As soon as the pliers have travelled a few centimeters, they rotate by ninety degrees,
thus causing the last bag of the package to rest on a sliding plane or slide and then
said pliers pull the package towards the end of the machine, thus allowing to keep
it taught and supported on an almost continuous plane, whatever the length of the
model of the bag produced. From here, a transverse cylinder sends the package towards
an automatic binding device. Due to reasons of practicality in the successive handling
operations, said packages are made with a number of bags varying from 50 to 100 pieces,
generally the bags are made of paper or of paper and transparent film so the contents
may be viewed. During the movement towards the unloading of the pliers with their
package of bags, the spreader, passing below the package being produced, is repositioned
towards the drum where the bags produced continuously are formed and are outlet, waiting
for the set quantity to be made and also for the pliers, which are arranged on a linear
actuator, they also oscillating downwards, to return below the package being produced
in open position to seize the new package formed at the proper count.
[0008] The device herein referred to as a spreader is fundamental to the present unloading
system, which spreader divides two adjacent packages with certainty, the spreader
being provided with two oscillations which are fundamental to the whole assembly,
a primary one where the whole spreader is arranged towards the drum behind the first
bag of the package being produced, and a secondary one where at the end of the package,
moved forwards, it opens on itself like scissors to allow the gripping of the pliers.
[0009] As already mentioned, these machines have high productions which reach 800 pieces
produced per minute, with variable dimensions of the different types of bags which,
in a common machine, vary for example, from dimensions of 8cm x 18cm up to 30cm x
75cm. This apparatus formed by spreader and pliers may operate indifferently on all
the sizes.
[0010] The different indexes, generally numerical, in the accompanying drawings have been
attributed with the meanings hereinafter indicated for easier reading of said drawings.
[0011] 100 Assembly of the outlet set and automatic unloading system of a machine called a bag
making machine, said set is formed by the outlet drum of the finished bags, its load-bearing
structure formed by a pair of lateral sheets, the unloading set, with wheeled plate
and outlet plate, with following a spreader system
300, a gripping system
200 with sliding pliers for recovering and transporting the bags and the possible overturning
of the package of bags at the unloading stop.
[0012] 200 Assembly of the complete gripping system, provided with trolley sliding linearly
with pliers, rotating by 90°, for gripping bags produced in preset number and horizontally
transported, after said rotation of 90 degrees, up to unloading onto an unloading
plane with possible movement and lateral binding.
[0013] 300 Assembly of the mechanical set forming the spreader, i.e. the mechanism selected
for separating the packages of bags, which one-by-one are picked by the pliers to
be moved away from the unloading system, packages with a predetermined number of bags,
the present spreader depicts the operating fulcrum of the present automatic unloading
system because it decides on the order and operating frequency between the production
drum and the packages of bags outcoming from the machine.
[0014] 210 Mechanical pliers provided with two flat gripping teeth, a fixed one and a movable
one by means of a pneumatic actuator, mounted with a hinge on the sliding trolley
and provided also with rotation, always by means of a second pneumatic cylinder.
[0015] 211 Pneumatic cylinder with sliding axis parallel to the closing direction of the pliers
themselves.
[0016] 215 Linear sliding trolley anchored to the movable slide of actuator
221.
[0017] 215/A, 215/B and 215/C Three positions of the pliers holder trolley are indicated during the movement thereby
from the gripping area
A, in motion
B, and rotated at stop for unloading in
C.
[0018] 216 Cylinder for the rotation of the pliers in order to spread the package taken over
the sliding plane.
[0019] 220 Transport assembly, actuator with trolley.
[0020] 221 Electric linear actuator, system with speed, acceleration and stop that can be adjusted
by the user.
[0021] 222 Pneumatic actuator, raises and lowers actuator
221 with complete trolley and pliers.
[0022] 230 Sliding plane of the package of bags transported to the unloading system by the pliers
210.
[0023] 232 U-shaped tracks on plane
230 to facilitate the lateral right-hand or left-hand unloading of the package of bags
towards a possible external binding device such as e.g. a strapping tool.
[0024] 305 Vertical cylinders or actuators for completely lifting and lowering the spreader
set
300.
[0025] 310 Shaped plates or in any case opening planes of the spreader or in any case spacers
of two adjacent packages of bags outcoming from the plate of the forming drum.
[0026] 312 Cylinders or actuators for the oscillation of the spreader plates
310, oscillation with respect to the axis of the hinges
316 arranged at the lower end of
310.
[0027] 315 Cylinders or actuators for opening/closing the two shaped plates
310 in the manner of scissors.
[0028] 316 Oscillating and opening hinge of the spreader, i.e. of the plates
310.
[0029] 325 Cylinder or actuator for positioning the whole spreader set for the start and
end loading cycle of the bags in the package of desired measurement.
[0030] 326 Hinge with spreader supports, thereon oscillating the whole set
300, moved by cylinder 325, which positions, as mentioned, the set at packing cycle start.
[0031] 400 Indication of the general package of bags completed.
[0032] 410 Package of bags during the formation of
400 not yet completed.
[0033] 500 Machine or set for producing bags, in particular the outlet drum of the finished
bags, said bag making machine with guides and supports of the bags.
[0035] 511 General puller of the bags produced.
[0036] 520 Structure of machine
500.
[0037] 550 Outlet and unloading set with wheels, plate, belts and guides for vertically stacking
the bags.
[0038] 600 Mechanical feeler that contains the package of bags towards the outlet rack.
[0039] 650 Lateral extraction cylinder of the package of bags towards the strapping or binding
device.
[0040] Passing now to a first examination summary of the accompanying drawings, and in particular
to the meaning of the different figures therein which depict the following.
Fig. 1 - From a comprehensive view of machine 500 which produces bags of various measures, with drum 510 and the unloading system 550 to which spreader 300 was applied, which separates package 400 of bags outcoming from that under production 410 and allows the pliers 210 to accompany it with the transport to the unloading system and to a possible packing.
Fig. 2 - View of device 300 as a whole.
Fig. 3 - Views, in the orthogonal projections, again of 300 with the detail of the various functional components operating the operating movements
of the spreader.
Fig. 4 - Side view of the transport system of the package of bags 400 pulled by the pliers 210 applied on the trolley of actuator 211 and perspective view of 220.
Fig. 5 and Fig. 6 - Describe the operating steps in sequence of the automatic unloading system of the
package of bags 400 operated by spreader 300 and pliers 200.
[0041] Starting again in detail with Fig. 1, from this first assembly, the operating principle
and concept of the subject of the present Patent may be traced back to, which, arranged
in line with machine
500 that produces the bags (herein depicted only in the final area, i.e. at the end of
the production of the bags themselves) on the unloading drum
510 where there are arranged the pliers of the drum itself which squeeze, transversely
to the tubular body, the glued and closed bottom of the bag, up to the collection
guides and table. As already mentioned, said machines may work with productions which
reach even 800 bags per minute, unloading them continuously with a bag serving as
a bookmark protruding at the end of each package, a package formed usually by a number
varying between 50 and 100 pieces.
[0042] The present automatic unloading system replaces the operators who manually take the
packages while binding them in different manners to tie them with elastics or strapping
or automatic binding while always manually supporting the bundle.
[0043] As mentioned, said automatic unloading system consists of two sets which are complementary
to each other, i.e. the first, spreader
300 dimensionally prepares the package of bags produced outcoming from the machine, generally
it separates from 50 to 100 pieces thereof, holds them vertically, even if they have
an increased length like the bags intended for fresh French bread, or
baguette, also up to 70-75 cm, then once the number of pieces is reached, it "detaches" the
completed package from the one being formed and therefore allows the gripping of the
first by the pliers set
200 provided with the transport movement, thus causing the package to slide on a specific
table
230 up to a final area where an actuator or a general transverse pusher moves it towards
a binding system, as used in these processing operations.
[0044] The successive table no. 2 in Fig. 2 notes the assembly mounted in perspective view
with all the actuators applied in
300 itself to provide a complete comprehensive depiction of the present set
300, while the successive Fig. 3 shows the three fundamental graphic views, where there
are noted all the actuators selected for the movements, for example of
310, opening/closing with
315, oscillating on
316 by means of
312 of
310, oscillating the whole set by means of
325 and finally, raining/lowering always the whole set by means of
305.
[0045] The shape of
310, spreader plates or planes, which are hollowed out in the lower area, towards
316, may also be noted, in order to allow the passage of the gripping teeth of the pliers
210 when they grip the bottom of the complete package
400 of the bags outlet from the forming machine.
[0046] The successive Fig. 4 is dedicated to the gripping pliers
210 with the different devices and actuators which characterize it both in the gripping,
211, and in the transport
221, indeed, starting from the right, where the spreader can be recognized, the pliers
210 may be recognized facing upwards,
215/A, in the specific function of gripping and seizing of
400 just formed. Then it moves towards plane
230 in position
215/B, taking gripped with it package
400 to rotate it, spreading it out, over plane
230 itself and pulling it up to releasing it in position 215/C of the trolley itself.
It is worth noting that by pulling and dragging package
400 to rotate it, the present transport system allows also working on very long packages
of bags which, as disclosed below, are carried vertically by a containment feeler,
therefore by releasing them therefrom, they rest on plane
230 to be easily unloaded onto a side of the plane for either a manual but also automatic
binding into bundles, as used and required in this field.
[0047] All the present description relates to the technical and mechanical structure of
the two groups
300 and
200, components and movements related to the pliers and the spreader selected for the
automatic unloading system; indeed to better clarify the continuous operation, hereinafter
and in Figures 5 and 6, the sequence of the operations is indicated while noting the
positions taken both by the spreader with its components and the pliers with their
trolley.
[0048] All steps have been indicated with the aid of Roman numerals from
I to
XVIII.
[0049] Step
I shows spreader
300 towards the drum waiting for the load of bags outcoming from the bag making machine,
II shows the pliers
210 open at the bottom and the plates
310 closed in top position, then in
III the formation of package
400 and the plates
310 stopped up high up to the completion of
400.
[0050] In
IV, the plates are rotated by the cylinders
312 and rotate to contain the end of the formation of
400 and allow the start of a new package
410 continuously but separately from the preceding one, like in
V, then the cylinders
315 spread the plates
310 as much as required to separate the bottom of the bags, position
VI. Then in
VII and
VIII, while more bags continue reaching the rack of the drum, cylinder
222 is raised with the pliers
210 while
325 executes the primary rotation of spreader
300.
[0051] In step
IX, there is the seizing by the gripping pliers of package
400 with feeler
600 which ensures the support towards the outlet of
400 itself, therefore in
X, 210 retracts and with the aid of
600, the bags are sent to rotate to the right, towards the drum, as shown in
X. Then in
XI, the gripped pliers
210 rotate by 90° towards the drum, actuator
216, while supporting package
400 on plane
230, and then
310 they are closed by means of the cylinders
315 and are lowered through the movement of the cylinders
305.
[0052] From position
V, a new bundle
410 is being formed which increments up to the end of step
XII, indeed at positions
XII and
XIII, while the pliers move away with
400, the lowered spreader rotates by means of
325 towards the drum and is raised again, repositioning itself behind the new package
410 in formation to begin a new cycle of separating the packages, while in
XIV the pliers
210 continue their operation, releasing their gripping of package
400 which in
XV is unloaded transversely by a pusher
650 to be bound or strapped here or also simply packaged outside the line for forming
the various packages
400.
[0053] At this point,
210 rotates by means of cylinder
216 (position
XVI) and travelling plane
230 (in
XVII), is repositioned in the "low" gripping position (in
XVIII) with cylinder
222 and the electromechanical actuator
221, which are arranged like in position
II, waiting for the unloading of the bags from the bag making machine to be completed
to form a package
400 and therefore resume the taking and transport cycle of this package
400.
[0054] As said many times, these packages of bags have highly variable parameters, from
the width to the length of the bag and the number in which they are packaged from
50 to 100. Therefore, this packaging system apparently resolves the problem of the
long and narrow bags contained here, at the time of unloading they are pulled by feeler
600 in the high and open area of the bag and by the pliers
210 from below, by individual package
400, towards the unloading system, while folding themselves naturally during the rotation
and pulling as is clearly noted in positions
X and
XI of Fig. 5, moreover, said rotation of
210 occurs at 250 mm from the start of the pulling of the bags which are supported on
plane
230.
[0055] It is apparent that what is depicted and described herein notes only one possible
practical, preferable but non-limiting embodiment of the present invention, which
may be different for arrangements of equipment and actuators, however without departing
from the conceptual scope underlying the invention.
[0056] Any reference numerals in the claims serve the sole and unique purpose of facilitating
the reading in light of the description and depictions in the accompanying drawings.
1. Automatic unloading system for bag making machines (100) applied at the outlet of
a rotating drum bag making machine for paper bags or bags made of paper and transparent
film, provided with a complete shaping system, from die-cutting to the formation of
the tubular body and of the finished bag, and provided with the outlet drum, and up
to a collection system towards a detachment rack, said unloading system being made
up of two sets of mechanisms complementary with respect to each other, the first set
(300) called spreader, which, through a sequence of movements of two shaped planes
(310) separates the package of bags (400) just formed by the bag making machine from
the following one 410 which is still being produced, the second set (200), called
gripping assembly, which comprises movable mechanical pliers (210) with shaped teeth
for being able to enter (310) and able to seize and take the package (400) just formed
by the bag making machine and separated from (410) by the planes (310), then to perform
a first movement away from the drum by one quarter of a metre and rotate the package
by 90 degrees, towards the drum, pulling it to the outlet of the gripping assembly
(200) itself on a sliding plane (230) by means of the glued part of the bags gripped
by (210), this to enable the transverse unloading of the package (400) with respect
to the sliding plane of the bags to also enable binding or strapping on machines arranged
next to said plane; all the movements of separation of the spreader (300) and of gripping
and rotation of the pliers (210) are obtained by means of pneumatic actuators, while
a linear actuator (221) for a movement slide of pliers (210) has a motion of electromechanical
origin with electronic controls.
2. Automatic unloading system according to the previous claim, characterized in that it includes a spreader (300) of packages of bags (400), coming continuously from
bag making machines, provided with two shaped metal planes (310) able to spread apart
two adjacent packages and allow for the insertion of the conjugated teeth of the pliers
(210) from below to take the glued bottoms.
3. Automatic unloading system according to the previous claims, characterized in that it includes a spreader (300) of packages of bags (400), wherein the planes (310)
can rotate simultaneously by an arc by means of an actuator (325) around the axis
(326) to assume two inclinations, one for the gripping by the pliers and one of cycle
start towards the production drum of the bags.
4. Automatic unloading system according to the previous claims, characterized in that it includes a spreader (300) of packages of bags (400), wherein the planes can open
like scissors by means of actuators (315) on (316) to spread apart the end of one
package and the beginning of the following one.
5. Automatic unloading system according to the previous claims, characterized in that it includes a spreader (300) of packages of bags (400), wherein the planes (310)
can further rotate together always around (316) to vary the inclination of the open
(310) and to divide the outcoming bags into two packages (400), and the beginning
of the new package (410).
6. Automatic unloading system according to the previous claim, characterized in that it includes a spreader (300) of packages of bags (400), wherein the whole set (300)
can be lifted and lowered with respect to the support plane of the package (400) with
actuators (305).
7. Automatic unloading system according to claims 2 to 6, provided with a spreader able
to separate the two packages of bags continuously coming out of a bag making machine
for paper bags or bags made of paper and a strip of transparent film.
8. Automatic unloading system according to the previous claims, provided with a gripping
device (210) by means of shaped teeth, which is linearly mobile with variable and
adjustable speed, applied to a trolley (215) moved by an electromechanical actuator
(211).
9. Automatic unloading system according to the previous claims, wherein the gripping
pliers (210) have shaped teeth able to enter the conjugated compartments of the planes
(310) to seize the package of bags (400) produced by the bag making machine from the
side of the glued bottoms, by means of a closing/opening actuator (211).
10. Automatic unloading system according to the previous claims, wherein the pliers (210)
can rotate by 90° on a hinge by means of the actuator (216) in order to orientate
according to the unloading plane (230) the package of bags (400), seizing them from
the side of the glued bottoms until unloading them onto said plane.
11. Automatic unloading system according to the previous claims, wherein the pliers (210),
applied to a trolley sliding on the actuator (221), can be lifted towards the spreader
(300), by means of an actuator (222), to take and pull the package (400) and then
be lowered again to return under (300) for a new cycle.
12. Automatic unloading system according to the previous claims, provided at the outlet
with a smooth sliding plane (230), for directing and support to the transverse unloading
towards binding machines.
13. Automatic unloading system (100), according to the previous claims, able to take and
move with the two complementary sets, the spreader (300) and the gripping set (200),
packages of bags (400) in a variable and pre-set number, from the unloading system
of a drum bag making machine for bags with folded and glued bottoms.
14. Automatic unloading system (100) according to the previous claims, able to take packages
(400) of 75 cm long baguette bags.
15. Automatic unloading system (100) according to the previous claims, able to take packages
(400) of bags made of paper only and bags with strips of transparent film.