U.S. patent application number 11/912100 was filed with the patent office on 2009-05-07 for system and method for treating flexible bags.
Invention is credited to Jurgen Beinghaus, Albert Schmitz.
Application Number | 20090113850 11/912100 |
Document ID | / |
Family ID | 36609535 |
Filed Date | 2009-05-07 |
United States Patent
Application |
20090113850 |
Kind Code |
A1 |
Beinghaus; Jurgen ; et
al. |
May 7, 2009 |
SYSTEM AND METHOD FOR TREATING FLEXIBLE BAGS
Abstract
A method for treating flexible bags, comprising transporting,
opening, filling and closing the bags in subsequent treatment
stations in which the bags are transported in holding devices on
several tracks from one treatment station to the next. In one
embodiment of the present invention, the bags are transported in a
continuous motion; during treatment, the respective treatment
station is moved from its initial position synchronously with the
motion of the bags; and after treatment, the respective treatment
station is returned to its initial position.
Inventors: |
Beinghaus; Jurgen;
(Wipperfurth, DE) ; Schmitz; Albert; (Kurten,
DE) |
Correspondence
Address: |
PAUL, HASTINGS, JANOFSKY & WALKER LLP
875 15th Street, NW
Washington
DC
20005
US
|
Family ID: |
36609535 |
Appl. No.: |
11/912100 |
Filed: |
April 18, 2006 |
PCT Filed: |
April 18, 2006 |
PCT NO: |
PCT/DE2006/000672 |
371 Date: |
July 30, 2008 |
Current U.S.
Class: |
53/468 ;
53/570 |
Current CPC
Class: |
B65B 43/465
20130101 |
Class at
Publication: |
53/468 ;
53/570 |
International
Class: |
B65B 43/26 20060101
B65B043/26 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 20, 2005 |
DE |
10 2005 018 441.3 |
Apr 21, 2005 |
DE |
10 2005 018 699.8 |
Claims
1-20. (canceled)
21. A method for treating flexible bags at a series of treatment
stations, comprising: opening the flexible bags at a first
treatment station; filling the flexible bags at a second treatment
station; and closing the flexible bags at a third treatment
station; wherein the bags are transported in holding devices
located on multiple lines from one treatment station to the next,
wherein the bags are transported in a continuous motion, and
wherein the bags are picked up on several lines from a transfer
position by a continuously operating transfer structure and
delivered on several lines to a bag transportation system that
passes the treatment stations.
22. The method in accordance with claim 21, wherein the bags are
produced and transported to the transfer position in a clocked
manner.
23. The method in accordance with claim 1, wherein during treatment
of the flexible bags, the corresponding treatment station is moved
continuously from its initial position synchronously with the
motion of the bags and subsequent to treatment the corresponding
treatment station is returned to its initial position.
24. The method in accordance with claim 21, wherein the bags are
suspended while being transported.
25. The method in accordance with claim 21, wherein the bags are
transported standing in nests.
26. The method in accordance with claim 21, wherein the bags in at
least one line differ in at least one of type, size, type of
filling and other such parameters from bags in other lines.
27. The method in accordance with claim 21, wherein during the
return of the treatment station, the speed is greater than or equal
to the speed in the moving step.
28. A method for treating flexible bags at a series of treatment
stations, comprising: changing a web of film into a roll; sealing
the roll in a clocked manner; cutting the roll to create flexible
bags with one open end; gripping the bags and transporting the
flexible bags in a clocked manner to a transfer position; when in
the transfer position, releasing the flexible bags; opening the
flexible bags at a first treatment station; filling the flexible
bags at a second treatment station; and closing the flexible bags
at a third treatment station; wherein the bags are transported in
holding devices located on multiple lines from one treatment
station to the next, wherein the bags are transported in a
continuous motion, and wherein the bags are picked up on several
lines from a transfer position by a continuously operating transfer
structure and delivered on several lines to a bag transportation
system that passes the treatment stations.
29. The method in accordance with claim 28, wherein during
treatment of the flexible bags, the corresponding treatment station
is moved continuously from its initial position synchronously with
the motion of the bags and subsequent to treatment the
corresponding treatment station is returned to its initial
position.
30. The method in accordance with claim 28, wherein the bags are
one of suspended while being transported and transported while
standing in nests.
31. The method in accordance with claim 28, wherein the bags in at
least one line differ in type, size, type of filling and other such
parameters from bags in other lines.
32. The method in accordance with claim 21, wherein during the
return of the treatment station, the speed is greater than or equal
to the speed in the moving step.
33. A system for treating flexible bags, comprising: at least one
treatment station for opening the flexible bags; at least one
treatment station for filling the flexible bags; at least one
treatment station for closing the flexible bags; at least one bag
transportation system that is configured to move the flexible bags
past the treatment stations; and a transfer structure that is
configured to operate continuously and pick up the flexible bags
from a transfer position and deliver them to at least one bag
transportation system.
34. The System in accordance with claim 33, wherein the bag
transportation system comprises: a plurality of mechanical holding
devices configured to hold the flexible bags; a first driving
structure configured to continuously move the plurality of
mechanical holding devices through the system, wherein the system
farther comprises an additional driving structure that includes one
or more driving assemblies for the treatment stations, the
additional driving structure configured to move a respective
treatment station synchronously with motion of flexible bags to be
treated during treatment and configured to return the respective
treatment station to its initial position after treatment.
35. The system in accordance with claim 33, wherein the additional
driving structure comprises at least one independent driving
assembly for each treatment station.
36. The system in accordance with claim 33, further comprising a
plurality of transport elements, wherein each transport element is
defined by a plurality of mechanical holding devices, wherein the
transport elements are linked without the use of additional linking
elements.
37. The system in accordance with claim 36, further comprising a
control structure for the mechanical holding devices, the control
structure configured to centrally control an opening and a closing
of the flexible bags.
38. The system in accordance with claim 37, wherein the opening and
the closing occur by means of a relative motion longitudinally or
laterally to a direction of movement of a transport element.
39. The system in accordance with claim 37, wherein, using a
relative motion that is lateral to a transport direction, the
mechanical holding device is adjustable by manual, semi-automatic,
or automatic means to one of a plurality of predetermined bag
widths.
40. A system for treating flexible bags, comprising: a device for
producing flexible bags that includes: a structure for changing the
shape of a web of film into a roll; a sealing and cutting structure
that is configured to cut flexible bags that are open at one end
from the roll; and a conveying structure that is configured to
transport sorted flexible bags arranged in a row to a transfer
structure; a treatment station for opening the flexible bags; a
treatment station for filling the flexible bags; a treatment
station for closing the flexible bags; a bag transportation system
that is configured to move the flexible bags past the treatment
stations; and a transfer structure that is configured to operate
continuously and pick up the flexible bags from a transfer position
and deliver them to the at least one bag transportation system,
wherein the transfer structure is configured to arrange the
flexible bags on several lines and to transfer the flexible bags to
the bag transportation system, and wherein the device for producing
flexible bags is configured to operate in a clocked manner, and
wherein and the transfer device is configured to operate
continuously.
41. The system in accordance with claim 40, further comprising a
transport element that includes a set of gripper strips and
includes a set of holding devices for holding the flexible bags
and, the holding devices being movable relative to each other.
42. The system in accordance with claim 41, wherein the gripper
strips hold the flexible bags in a stretched out fashion to fit a
predetermined line spacing.
43. The system in accordance with claim 41, wherein the transfer
structure comprises gripper strips for the flexible bags.
44. The system in accordance with claim 43, wherein at a time of
transfer and in a transfer position, the gripper strips of the
transfer structure open while the gripper strips of the transport
system close simultaneously.
45. The system in accordance with claim 41, further comprising
mechanical structures to facilitate a relative motion of the
holding devices, which is controlled by continuous transport motion
of the flexible bags, wherein the system is configured to fill
spatially and temporally independently at least one storage unit,
and to transfer the storage unit to an inventory unit that sorts
the flexible bags according to minimum filling capacity.
Description
[0001] The present application is the national phase of
International Patent Application No. PCT/DE2006/000672, filed Apr.
18, 2006, which claims priority to German Patent Application Nos.
102005018441.3 filed Apr. 20, 2005 and 102005018699.8 filed Apr.
21, 2005, which are herein incorporated by reference in their
entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to a method for treating
flexible bags, especially for transporting, opening, filling and
closing the bags in subsequent treatment stations by transporting
the bags in holding devices on multiple lines from one treatment
station to the next. Furthermore, the invention relates to a system
for treating flexible bags which are particularly suitable for the
implementation of the method.
BACKGROUND OF THE INVENTION
[0003] Methods and systems for treating flexible bags are
well-known. The applicant, for example, has for years distributed
an structure whereby bags are suspended on holding devices which
are fitted onto a rotating device and led past different treatment
stations which comprise opening means, filling means for solid or
liquid material and, finally, closing means. In US 2004/0011008 A1,
a transfer device feeds bags to a clocked rotating device by way of
a storage unit.
[0004] EP 1 164 081 A1 discloses a transfer structure which moves
single, clocked, successively arriving bags by means of a suction
holding device to a filling and packaging structure.
[0005] EP 1 043 233 A1 discloses a filling and packaging system
comprising bags which are held in holding devices and led past
treatment stations on a circulating transportation device. The bags
are supplied by a supply structure that moves synchronously with
the transportation structure.
[0006] EP 0 908 386 B1 discloses a method and device for treating
flexible bags comprising web film bags that undergo various
treatments at various operating speeds. Several bags simultaneously
and synchronously pass the treatment station while suspended in a
row moving perpendicular to the direction of movement. In this
manner, the bags are treated simultaneously and synchronously in a
row in a stationary treatment station. The bags are suspended in
the holding devices on a receiving element comprising at least two
holding devices per bag whereby the first holding device and the
corresponding second holding device are movable relative to each
other.
[0007] The device disclosed in DE 103 22 556 A1 for treating
containers is particularly suitable for filling and closing
bottles, pots or cans. In other words, containers with stable
shapes which are led past various treatment stations by a conveyer
unit that is also continuously operated. The containers are
correspondingly continuously transported to gripper elements which
are not described in any further detail and which place the
containers in receiving elements in the conveying structure.
[0008] WO 99/44892 discloses a method for producing containers
which are suitable for automatic filling from a web of flexible
material. To this end, successions of horizontally oriented bags
are reoriented to successions of vertically oriented bags which are
still arranged in a row. Each device for opening, filling and
sealing is fitted on an endless loop chain that extends in a
horizontal direction. Each treatment station performs a
synchronized horizontal motion with the containers that are to be
treated and that are arranged on an endless loop chain that extends
in a vertical direction. This system operates on one line which in
addition to the one transport line comprises structures for
shaping, filling and sealing the containers.
[0009] U.S. Pat. No. 4,330,288 relates to a packaging machine that
comprises a mechanism for transferring and opening bags. Bags are
successively cut and then each bag is gripped. The bags are then
led to a continuous endless chain in the respective filling and
cutting sections. To allow the bags to be turned after cutting in
such a way that they can enter the machine, the system can be
adjusted to have a constant center distance that is smaller than
had the bags been successively transported edge to edge. In this
way the machine operation route is shorter.
[0010] US 2003/0233812 A1 discloses a method for filling flexible
bags which subsequently are treated in several parallel lines. The
conveying structure is continuous. The carrier chain for the
filling section or, as the case may be, the sealing section, must
be aligned with the conveying structure for the bags and must be
moved at the same speed.
[0011] EP 1 249 400 A2 relates to a continuous conveying type bag
filling machine comprising an empty bag supplying device whereby
said device receives empty bags on a vertical plane and picks up
these empty bags with the opening facing up and moves them to
corresponding gripper pairs in the continuous conveying type bag
filling machine. The gripper pairs are continuously moved at a
constant speed and, with uniform spacing between them, they grip
both edges of the bag with gripper sections to move the suspended
bag on a vertical plane. Downward-facing bag holding members which
open and close at a specified rate and when closed hold the upper
parts of the bag, perform a back and forth motion along an
arc-shaped path on a horizontal plane, said motion being caused by
a back and forth mechanism that also causes the bags that are held
by the holding members to be set substantially parallel to a
direction of movement of said gripper pairs at all times. The speed
of the back and forth motion of the bag holding members in the
direction of movement of the gripper pairs is set to be
substantially equal to a moving speed of said gripper pairs at
least within the bag transfer region. The arc-shaped path comprises
an intermediate point at the beginning of the forward motion.
SUMMARY OF THE INVENTION
[0012] It is the object of the present invention to provide a
method and a system for treating flexible bags which facilitates
rapid and effective treatment of the bags.
[0013] Aspects of the present invention that include a method and
system that achieve this object are recited in the claims herein.
Preferred embodiments are recited in the dependent claims. Aspects
of a device for producing flexible bags which are particularly
suitable for the implementation of a system for treating flexible
bags are also recited in the claims herein.
[0014] According to the invention, a method for treating flexible
bags that involves transport of the bag holding devices on multiple
lines from one treatment station to the next and transporting the
bags in a continuous motion, comprises using a continuously moving
transfer structure that picks up the bags from a transfer position
on several lines and delivers them on several lines to a bag
transport system that passes treatment stations. The treatment of
the bags is particularly quick since several bags are being picked
up and delivered simultaneously. The method is effective because it
comprises only a single transfer structure, which requires only a
single driving assembly. Preferably, the bags are both produced and
transported to the transfer position in a clocked manner.
[0015] The bags could be transported while suspended whereby they
are held in mechanical holding devices laterally or longitudinally
to the transport direction. The bags could also be transported in
standing position in nests which, for example, simplifies handling
in connection with a storage and provisioning unit which is
described in further detail below. The bags, usually those with a
round standing surface, would then be conveyed in the suspended
nests instead of being gripped individually by the mechanical
holding devices.
[0016] The advantage of the suspended transportation method is that
the volume of the bag is of no relevance to the operation process.
In a preferred embodiment of the invention, the bags in at least
one line differ with respect to type, size, type of filling and
other such parameters from bags in the other lines. This means that
not only different bags can run through the same system but
different products can also be filled into the bags. The number of
lines on which the bags are transported through the system
determines the maximum number of different bags and products that
can be used.
[0017] Preferably, the production of bags occurs, firstly, as at
least one film web is formed to a roll. Then, the roll or rolls are
sealed and cut in a clocked manner to produce bags that are open at
one end. The bags are then gripped and, in a clocked manner,
transported to a transfer position where they are released and
simultaneously picked up to achieve continuous motion. The bags are
preferably suspended while being transported and the relative
suspended position cannot be changed between the pick up and the
transfer steps.
[0018] The system according to the invention for treating flexible
bags comprises at least one treatment station in which the bags are
opened, filled or closed and a bag transportation system that moves
the bags past treatment stations as well as a continuously
operating transfer structure which picks up bags from a transfer
position and delivers them to the bag transportation system. The
system is effective because only a single transfer structure is
associated with only a single driving device and the system
operates faster since said single transfer structure picks up
several bags simultaneously and in a parallel manner.
[0019] Preferably, the system comprises mechanical holding devices
for the bags and a driving structure for the mechanical holding
devices whereby said driving structure continuously moves the
mechanical holding devices through the system. An additional
driving structure, which may comprise several driving assemblies,
is provided for the treatment stations, which move the treatment
station during treatment synchronously with the motion of the bag
to be treated and which bring the treatment station back to its
respective initial position after treatment. For this purpose, it
is preferable if this additional driving structure comprises one or
several independently working driving assemblies for every
treatment station.
[0020] Preferably, the bags are transported in holding devices on
multiple lines from one treatment station to the next, whereby,
unlike in prior art, the bags then are transported in a continuous
motion which practically prevents mass velocity of the content of
the bags. During treatment, the respective treatment station is
moved from its initial position synchronously with the motion of
the bags and, after treatment, the respective treatment station is
returned to its initial position to commence treatment of the newly
arrived bags.
[0021] Preferably, the speed of the treatment station during the
return is greater than or equal to the speed during the treatment
period.
[0022] The bags could be transported while suspended whereby they
are held in mechanical holding devices laterally or longitudinally
to the transport direction. The bags could also be transported in
standing position in nests which, for example, simplifies handling
in connection with a storage and provisioning unit which is
described in further detail below. The bags, usually those with a
round standing surface, would then be conveyed in the suspended
nests instead of being gripped individually by the mechanical
holding devices.
[0023] The advantage of the suspended transportation method is that
the volume of the bag is of no relevance to the operation process.
In a preferred embodiment of the invention the bags in a least one
line are different with respect to type, size, type of filling and
other such parameters than bags in the other lines. This means that
not only different bags can run through the same system but
different products can also be filled into the bags. The number of
lines on which the bags are transported through the system
determines the maximum number of different bags and products that
can be used.
[0024] Preferably, the production of bags occurs, firstly, as at
least one film web is formed to a roll. The roll or rolls are then
sealed and cut in a clocked manner to produce bags that are open at
one end. The bags are then gripped and, in a clocked manner,
transported to a transfer position where they are released and
simultaneously picked up to achieve continuous motion. The bags are
preferably suspended while being transported and the relative
suspended position cannot be changed between the pick up and the
transfer steps.
[0025] The system according to the invention for treating flexible
bags comprises at least one treatment station which opens, fills or
closes the bags, with mechanical holding devices for the bags and
with a driving structure for the mechanical holding devices whereby
said driving structure continuously moves the mechanical holding
devices through the system. An additional driving structure is
provided for the treatment station which moves the treatment
station during treatment synchronously with the motion of the bag
to be treated and which brings the treatment station back to its
respective initial position after treatment. For this purpose, it
is preferable if this additional driving structure comprises one or
several independently working driving assemblies for every
treatment station, whereby the interaction of all driving
assemblies is facilitated by a superordinate control structure. In
this manner it is, for example, possible to carry out not only the
required back and forth motion in a treatment station but also an
up and down motion if necessary.
[0026] It is preferable if the system according to the invention
comprises several transport elements whereby several mechanical
holding devices are integrated into a transport element and the
corresponding holding devices each define a transport element on a
treatment line. Such a link of transport elements forms a closed
gripper chain without the need for additional linking elements
allowing several flexible bags to be transported in a row on
multiple lines. The number of holding devices in a transport
element varies and determines the number of lines used in the
system.
[0027] A control structure for the mechanical holding devices
centrally controls the opening or closing motion of the bag,
preferably using a relative motion laterally or longitudinally to
the direction of movement of the transport elements.
[0028] It is particularly preferable that the mechanical holding
devices can, at least partly, be either manually or automatically
adjusted to fit one or several different bag widths by way of a
relative motion lateral to the transport direction.
[0029] In preparation for treatment in the system according to the
invention a device is provided for producing flexible bags from a
web of film which comprises a structure that changes the shape of
the web of film into a roll and a sealing and a cutting structure
which cuts bags that are open at one end from the roll. In this
manner, the bags are intermittently or continuously produced on a
line, or, in other words, on a single line. The bags can also be
cut from one endless string of bags on multiple lines. When the
film is cut, individual bags are formed which are arranged in a row
and, in accordance with the invention, are then transported to a
transfer structure which in accordance with the objectives of the
system for treating flexible bags, arranges the bags on multiple
lines and delivers them to the system.
[0030] The device for producing flexible bags operates in a clocked
manner while the transfer structure operates continuously. In
accordance with the present invention, the transfer structure
connects the clocked bag separator with the continuously working
treatment station for the flexible bags. In this connection, the
transfer structure is designed in such as manner that the relative
motion of transferring transport elements to transport elements
that pick up over a predetermined transfer path equals zero and the
relative suspended position of the bags will not change.
Preferably, the bags are held stretched out in the transfer
structure by holding strips to match the line spacing that will
later be needed. The transport system also comprises a gripper
system for bags which is fitted with gripper strips that, like the
arriving bags, are led to the transfer position in a continuous
motion. The simultaneous opening and closing motion of the gripper
system holding strips or gripper strips in the conveying structure
and in the transfer structure facilitates precise transfer.
Finally, transportation of the bags resumes in a continuous
motion.
[0031] According to the present invention it is often practical to
store and sort bags and then allow later introduction to the system
on multiple lines by means of a transfer structure. Therefore, it
is particularly preferable if at least one storage unit is filled
spatially and temporally independently from the rest of the bag
treatment process. Finally and as needed, the bags are
automatically assigned a storage unit which sorts the bags
according to minimum filling capacity. The advantage of this
approach is that the process of the subsequent system can run
continuously without interruption and does not require additional
personnel.
[0032] Preferably the system comprises structures for the relative
movement of the holding devices which are controlled by the
continuous transport motion of the bags, eliminating the need for
employment of an additional motor.
[0033] The transport system and the transfer structure are both
characterized by the fact that they are not fitted with driving
structures but have devices for the relative motion of the holding
devices which hold the bags and which are controlled by the
continuous transport motion of the bags.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] FIG. 1 is a perspective view of a system for treating
flexible bags that is operated in accordance with the method of the
present invention.
[0035] FIG. 2 is a view that illustrates details of the transport
system.
[0036] FIG. 3 is a detailed view of FIG. 2.
[0037] FIG. 4 is an enlarged frontal view of the system in FIG.
1.
[0038] FIG. 5 is a representation of the device that grips the
flexible bags and that also can facilitate a central format
conversion.
[0039] FIG. 6 is a perspective view of the entire structure
comprising devices for producing bags and the system in FIG. 1.
[0040] FIG. 7 is a perspective view of the transfer structure which
connects the device for producing the bags with the transport
system in FIG. 3.
[0041] FIG. 8 depicts a storage unit with structures for storing
and separating bags which are kept ready for the system in
accordance with the invention.
[0042] FIG. 9 depicts the device in FIG. 5 placed in front of the
device in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0043] FIG. 1 shows a perspective view of a system for treating
flexible bags according to an embodiment of the present invention
which comprises a treatment station 10 which in successive steps
takes over the bags, opens them and if necessary performs an
inspection to verify if an open bag is duly suspended on every
holding device 14, a filling station 20 and a closing station 30.
As is easier to see in FIG. 2, bags run on several lines in the
treatment station 10, and in this case the bags are held by a
transport element 12 and run in eight lines into the treatment
station 10. In this connection, a transport element 12 comprises
opposite facing holding devices 14 which can be adjusted to fit
various bag widths by means of a relative motion laterally to the
transport direction A whereby the adjustment occurs centrally. The
relative motion can be controlled either manually or automatically.
The suspended bags are held by the holding devices 14 and, as can
be seen in FIG. 1, are continuously led through the system 100, not
in a clocked manner as in prior art, and are treated there. The
corresponding treatment stations 10, 20, 30 are continuously moved
with the bags on the respective transport element during the
treatment and return to their initial position subsequent to
treatment. Corresponding driving assemblies, such as 105, 110, 115,
120, which facilitate the back and forth motion of the treatment
stations and, if necessary, the up and down motion of an entire
station or parts thereof, are fitted to the frame portal, for
example 130, 140 which also carry all other components of the
treatment station, for example 10, as shown here. The described
arrangement prevents the stand-still of the transport elements 12
or the bags suspended in it so that when liquid is being filled
into the bags the danger of spillage is extensively eliminated. In
the closing station 30, the filled bags are sealed either thermally
or using ultra sound or sealed using other sealing processes.
Subsequently, the bags may optionally be cooled to achieve better
impermeability of the sealing seam.
[0044] FIG. 2 shows details of the transport system which leads the
bags through the various treatment stations 10, 20, 30 (FIG. 1).
Gripper strips 330 on which the holding devices 14 are fitted are
moved through the system by way of driven tracks 310, 312. The
relative motion of the holding devices 14 which are shown clearer
in FIG. 3 with suspended bags 300 in them occurs during the
continuous transport without the use of a separate driving
structure by way of a superimposed motion that is derived from the
transport motion. The same applies to the opening and closing
motion of the holding devices 14 on the treatment station 10 and
the closing station 30. Mechanical structures 320, 322, 324, 326
are provided in pairs on each side of the transport system and they
allow the holding devices 14 on the gripper strips 330 to perform
the relative motion necessary for the respective treatments.
[0045] FIG. 4 shows an enlarged view of the view in FIG. 1 in which
the transfer position of the treatment station 10 is easier to see.
Every holding device 14 comprises holding elements (bag gripper
pairs) which are movable relative to each other and which can be
operated perpendicular to the transport direction A by means of a
driving structure 200. The transport elements 12 which are attached
to a carrier 16 move the held bags to the transfer grippers 18 from
where they are moved to additional treatment steps, firstly for the
opening of the bag.
[0046] In FIG. 5 it is more evident how the relative motion of the
holding devices 14a, 14b in the direction of the arrow B, in other
words, perpendicular to the transport direction A, is suitable for
the adjustment by means of a central format adjustment unit 30 to
fit different bag sizes.
[0047] Depending on the spacing between the opposite placed
elements 14a and 14b, bags of different widths can be processed. A
bag nest 22 which is depicted in an almost phantom-like manner is
an alternative to the holding device 14 or the holding elements 14a
and 14b. The relative motion of the holding devices 14a, 14b also
causes the bags to open or close, a motion that is controlled by
the transport motion as was discussed in connection with FIGS. 2
and 3.
[0048] FIG. 6 shows a perspective view in which the system 100 for
treatment of flexible bags from FIG. 1 is centrally placed. On both
sides of the system 100, mirror-symmetrically to area C are devices
that keep the bags ready for treatment in the system. Firstly, the
film material in the form of a strip is readied and prepared to a
roll in stations 40 or 40' and then led to a sealing machine 50 or
50'. Behind the sealing machine is a cooling station 60 or 60'. The
material in the form of a strip is then led to a printer 70 or 70'
for coding and finally pre-embossing in presses 80 or 80' before it
is cut into individual bags in a cutting station 90 or 90', said
bags being arranged in a row. The sorted bags are introduced to the
system by means of a transfer structure on multiple lines in
accordance with the objectives of the system 100 or the transport
elements 12. In the embodiment shown in FIG. 6, two devices for bag
production are symmetrically arranged so that they each operate on
one half of the line.
[0049] FIG. 7 shows the transfer structure which connects the bag
sorting unit with the bag transport system which is shown in FIG.
2. In a practical embodiment, the transfer structure is arranged on
the device described in connection with FIG. 2 in such a way that
the transfer grippers 710, which are more clearly depicted in
position 720, collect the bags from the correct place in the bag
sorting location. In this connection, the transfer gripper 720
comprises latch rails 722 which press on the bags to immobilize
them. Should the simple method of using latch rails 722 not
suffice, suction pressure can be used to achieve a vacuum
connection 714, 724 which will further aid in holding the bags.
Bags are assumed by a transfer gripper system on multiple lines at
the transfer position of the bag sorting step and are in this way
held by the transfer grippers 710, 710. In this way, the bags are
held stretched out to match the spacing between the lines of the
transport system. The transfer is analogous to the process
described in connection with FIGS. 2 and 3 during the continuous
transport motion of the transfer gripper system.
[0050] The opening and closing motion of the transfer gripper thus
occurs without the aid of a separate drive, but rather is achieved
using the superimposed closing and opening motion of the transport
motion. In this manner, precise pick-up and transfer is possible.
Subsequent to pick-up, the bags are moved in a continuous motion to
the transport system in FIG. 2. During this step, the relative
suspended position of the bags between pick-up and transfer does
not change. These simultaneous opening and closing motion of the
gripper system is also important to facilitate precise transfer. In
addition, the transfer gripper systems are led in circumferential
parallel-guiding mechanisms.
[0051] It is also possible to initially produce the bags and
temporarily store them in a storage unit 500 as is shown in FIG. 8.
The storage unit 500 is designed to correspond to the number of
lines used in the system, in this case eight lines, and preferably
it can easily be disconnected from the provisioning element 510 and
be replaced by another storage unit. In the provisioning element
510, protected by a hood 512, bags which are destined for the
sorting step 520 are stored. Said step is fitted with a sensor for
the minimum filling capacity of bags so that it, for example, can
be determined that there is sufficient material left for a certain
amount of operating time but that after this time no transfer can
occur. The provisioning element 510 ensures that there is enough
bag material for the sorting step 520. When the provisioning
element 510 is empty a storage unit 500 delivers more bags. In this
manner, the bags can automatically be forwarded to the transfer
structure without the need for additional personnel.
[0052] Finally, in FIG. 9 the device shown in FIG. 8 is placed in
front of the system shown in FIG. 1 so that the sorted bags can be
transferred to the system in FIG. 1.
[0053] The characteristics of the invention revealed in the above
specifications, in the drawings, as well as in the patent claims,
could be significant for the realization of the invention
individually as well as in any combination.
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