U.S. patent application number 15/464280 was filed with the patent office on 2017-09-21 for method and apparatus for banding rolls with paper.
This patent application is currently assigned to CMD Corporation. The applicant listed for this patent is CMD Corporation. Invention is credited to Thomas C. Jansen, Gregory Johnson, Gregory J. Prellwitz, Paul A. Selle, Christopher L. White.
Application Number | 20170267384 15/464280 |
Document ID | / |
Family ID | 59848160 |
Filed Date | 2017-09-21 |
United States Patent
Application |
20170267384 |
Kind Code |
A1 |
Selle; Paul A. ; et
al. |
September 21, 2017 |
Method and Apparatus For Banding Rolls With Paper
Abstract
A method and apparatus for banding rolls of bags is disclosed.
It can include a bag machine and/or a winder as the source of
rolls. The bander includes multiple banding stations. The source of
rolls provides rolls at a faster rate than any banding station can
apply bands. By selectively using each banding station the bander
can have the same throughput as the source of rolls of bags.
Inventors: |
Selle; Paul A.; (Appleton,
WI) ; White; Christopher L.; (Little Suamico, WI)
; Jansen; Thomas C.; (Appleton, WI) ; Prellwitz;
Gregory J.; (Black Creek, WI) ; Johnson; Gregory;
(Greenville, WI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CMD Corporation |
Appleton |
WI |
US |
|
|
Assignee: |
CMD Corporation
Appleton
WI
|
Family ID: |
59848160 |
Appl. No.: |
15/464280 |
Filed: |
March 20, 2017 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
62310374 |
Mar 18, 2016 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B65B 63/04 20130101;
B65B 27/10 20130101; B65B 25/146 20130101 |
International
Class: |
B65B 11/04 20060101
B65B011/04; B65B 31/00 20060101 B65B031/00; B65B 41/12 20060101
B65B041/12; B65B 51/06 20060101 B65B051/06 |
Claims
1. A bander for rolls of bags comprising: a source of a plurality
of rolls of bags; a first banding station including a first cradle
and a first band applicator disposed to receive a first source of
bands and apply a first band to a first roll in the first cradle; a
second banding station including a second cradle and a second band
applicator disposed to receive a second source of bands and apply a
second band to a second roll in the second cradle; and a roll
diverter positioned to receive the plurality of rolls of bags from
the source of rolls of bags, and to selectively direct the
plurality of rolls of bags into the first banding station and the
second banding station, wherein any particular roll is diverted
into only one of the first banding station and the second banding
station, and wherein the plurality of rolls of bags includes a
first group of bags diverted into the first banding station and the
plurality of rolls of bags includes a second group of bags diverted
into the second banding station; wherein a roll path includes a
source of rolls of bags, followed by the roll diverter, followed by
the first banding station and the second banding station.
2. The bander of claim 1, wherein the bander includes a plurality
of additional banding stations, each additional banding station
including an additional cradle and an additional band applicator
disposed to receive an additional source of bands and apply an
additional band to an additional roll in the additional cradle, and
wherein the roll diverter is further positioned to direct the
plurality of rolls of bags into the plurality of additional banding
stations, and wherein the roll path further includes the plurality
of additional banding stations.
3. The bander of claim 1: wherein the first band applicator
includes a first liquid applicator that extends in the cross
direction a portion of the first band, disposed to apply liquid to
only a first part of the first band in the cross direction, and to
not apply liquid to a second part of the first band in the cross
direction; and wherein the second band applicator includes a second
liquid applicator that extends in the cross direction a portion of
the second band, disposed to apply liquid to only a third part of
the second band in the cross direction, and to not apply liquid to
a fourth part of the second band in the cross direction.
4. The bander of claim 1, wherein the first band applicator
includes a first vacuum conveyor disposed to convey the first band
and wherein the second band applicator includes a second vacuum
conveyor disposed to convey the second band.
5. The bander of claim 4, wherein the first and second banding
stations each include at least one mandrel disposed to hold the at
least one of the plurality of rolls.
6. The bander of claim 5, wherein the first banding station
includes a first source of air disposed to direct the first band
and wherein the second banding station includes a second source of
air disposed to direct the second band.
7. The bander of claim 6, wherein the first band applicator
includes a first plurality of flexible fingers disposed to guide
the first band, and wherein the second band applicator includes a
second plurality of flexible fingers disposed to guide the second
band.
8. The bander of claim 1, wherein the source provides the plurality
of rolls of bags at a first given rate, and wherein the bander
includes a plurality of additional banding stations, each
additional banding station including an additional cradle and an
additional band applicator disposed to receive an additional source
of bands and apply an additional band to an additional roll in the
additional cradle, and wherein the roll diverter is further
positioned to direct the plurality of rolls of bags into the
plurality of additional banding stations, and wherein the roll path
further includes the plurality of additional banding stations, and
wherein each of the first, second and plurality of additional
banding stations operates at a second given rate, and wherein the
ratio of the first given rate to the second given rate is less than
the number of banding stations.
9. A machine for winding and banding rolls of bags comprising:
source of a plurality of bags; a winder, disposed to receive the
bags and wind them into a plurality of rolls of bags; a plurality
of banding stations, each including a cradle disposed to receive at
least one roll of the plurality of rolls of bags, and including a
band applicator, disposed to receive a plurality bands and apply
one of the plurality of bands to the at least one roll in the
cradle; a roll diverter positioned to receive the plurality of
rolls of bags from the winder, and to selectively direct the
plurality of rolls of bags into a one of the plurality of banding
stations, and wherein the plurality of rolls of bags includes a
first group of bags diverted into a first one of the plurality of
banding stations and the plurality of rolls of bags includes a
second group of bags diverted into a second one of the plurality of
banding stations; wherein a roll path includes the source of the
plurality of bags, followed by the winder, followed by the roll
diverter, followed by the first banding station and the second
banding station.
10. The machine of claim 9, wherein the source of the plurality of
bags is a bag making machine.
11. The machine of claim 10, wherein the plurality of banding
stations each includes a liquid applicator disposed to apply liquid
to part of the one of the plurality of bands.
12. The machine of claim 11, wherein the plurality of banding
stations each includes a vacuum conveyor disposed to convey the one
of the plurality of bands to the cradle.
13. The machine of claim 12, wherein each banding stations includes
at least one mandrel disposed to hold the at least one roll.
14. The machine of claim 13, wherein the plurality of banding
stations includes a source of air disposed to direct the one of the
plurality bands into the cradle.
15. The machine of claim 13, wherein the band applicator includes a
plurality of flexible fingers disposed to guide the one of the
plurality bands about the at least one roll in the cradle.
16. The machine of claim 13, wherein the winder winds the plurality
of rolls of bags at a first given rate, and wherein the a plurality
of banding stations operate at a second given rate, and wherein the
ratio of the first given rate to the second given rate is less than
the number of banding stations.
17. The machine of claim 13, wherein the winder includes two
winding stations.
18. A method for banding rolls of bags comprising: receiving a
plurality of rolls of bags; selectively directing a first group of
the plurality of rolls of bags into a first of a plurality of
banding stations; selectively directing additional groups of the
plurality of rolls of bags into additional banding stations of the
plurality of banding stations, wherein the directing is done
sequentially so that each banding station receives a one of the
plurality of roll of bags before any given banding stations
receives a second of the plurality of roll of bags; cradling each
roll of bags from each group of rolls of bags in the respective
banding station, and applying a band to each roll.
19. The method of claim 18, further comprising receiving a
plurality of bags, and wherein receiving a plurality of rolls of
bags includes winding rolls of bags from the plurality of bags.
20. The method of claim 19, wherein winding rolls of bags includes
first directing a portion of the plurality of bags to a first
winder, then directing a portion of the plurality of bags to a
second winder, and repeating, and further includes winding the bags
in a first direction using the first winder, and winding the bags
in a second direction using the second winder, and wherein
selectively directing includes directing at least partially based
on whether a given roll was wound in the first direction or the
second direction.
21. The method of claim 19, wherein receiving a plurality of bags
includes forming bags from film.
22. The method of claim 19, wherein winding rolls of bags from the
plurality of bags is performed at a first given rate, and wherein
each of the a plurality of banding stations operate at a second
given rate, and wherein the ratio of the first given rate to the
second given rate is less than the number of banding stations.
23. The method of claim 18, wherein applying a band includes
applying liquid to the band.
24. The method of claim 23, wherein applying a band further
includes applying suction to the band to convey the band.
25. The method of claim 24, wherein applying a band further
includes directing air to the band.
Description
FIELD OF THE INVENTION
[0001] The present disclosure relates generally to the art of
machines that process rolls of bags. More specifically, it relates
to a bander.
BACKGROUND OF THE INVENTION
[0002] Rolls of bags (such as tall kitchen bags) made from film are
common in the industry. Bags may be made using various machines
such as a rotary overlap machine (see U.S. Pat. No. 5,377,929,
Gietman et al., hereby incorporated by reference, and U.S. Pat. No.
8,029,428, Selle et al, hereby incorporated by reference). Some
machines include a winder, and other machines are used with
separate winders. High speed winders are described in U.S. Pat. No.
7,578,779 and US 2009-0019817 A1, both Selle, et al., and hereby
incorporated by reference. The speed of some bag making machines
and winders can be 600 feet per minute, which makes about 240 bags
per minute, for 30 inch tall kitchen bags.
[0003] After being wound into a roll bags are packaged. Rolls in
boxes are preferred in some markets, but in other markets less
packaging is preferred. Providing a paper or plastic band around
the roll to hold the roll in place uses little packaging, reducing
waste and cost of materials. Also, it provides a location (the
band) for the manufacturer to advertise. Paper bands typically have
glue, which is wetted and then wrapped around the roll. A quick
setting glue dries quickly, allowing the roll to moved and made
ready for shipping.
[0004] However, wetting and placing the band on a roll can be
difficult, and it is difficult to do so at speeds commensurate with
the speeds bags are produced. Rolls of bags can be produced in 1.5
seconds (or 40/minute). The banding has been performed by hand.
This can be slow, costly and unreliable. Automatic banders have
also been used, but are limited in speed to 10 rolls per minute.
Thus, the bander is often the speed limiting step for the bag
machine and winder.
[0005] Accordingly, and automated bander that can effectively band
rolls of bags at the speed the bags are produced is desired.
SUMMARY OF THE PRESENT INVENTION
[0006] According to a first aspect of the disclosure a machine
applies bands to rolls of bags. The machine includes two or more
banding stations and a roll diverter. A roll path includes a source
of the rolls of bags, followed by the roll diverter, followed by
the banding stations. Each banding station includes a cradle that
receives a roll, and includes a band applicator. The band
applicator receives bands and applies the band to the roll in the
cradle. The roll diverter receives the rolls of bags from the
source, and selectively directs each rolls of bags into one of the
banding stations such that any particular roll is diverted into
only one of the stations, and such that some of the rolls are
diverted into each banding station.
[0007] According to a second aspect of the disclosure a method for
banding rolls of bags includes receiving a plurality of rolls of
bags, and directing some of them into a first of a plurality of
banding stations. Additional rolls of bags are directed into
additional banding stations. The directing is done sequentially
such that each banding station receives one of the plurality of
roll of bags before any given banding stations receives a second.
In each banding station a roll of bags is cradled, and a band
applied thereto.
[0008] The winding includes a bag machine and/or winder in various
embodiments.
[0009] There are two, three, or more banding stations in various
embodiments.
[0010] Each band applicator includes a liquid applicator that
extends in the cross direction and applies liquid to only part of
the band in the cross direction, and does not apply liquid the rest
of the band in the cross direction in another alternative.
[0011] Each band applicator includes a vacuum conveyor that conveys
the bands in one embodiment.
[0012] Each banding station includes at least one mandrel disposed
to hold the roll in one alternative.
[0013] The banding stations includes a source of air that directs
the first band in another alternative.
[0014] The band applicators includes flexible fingers that guide
the bands in one alternative.
[0015] The source provides the plurality of rolls of bags at a
first given rate, and banding stations operate at a second given
rate, and the ratio of the first given rate to the second given
rate is less than the number of banding stations in one
embodiment.
[0016] The machine includes two winding stations in one
alternative.
[0017] The two winding stations each wind in a different direction,
and the rolls are directed to a banding station based at least
partially on which direction the roll was wound in another
alternative.
[0018] Other principal features and advantages of will become
apparent to those skilled in the art upon review of the following
drawings, the detailed description and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is schematic of a machine described herein;
[0020] FIG. 2 is schematic of a bander described herein;
[0021] FIG. 3 is schematic of a banding station described
herein;
[0022] FIGS. 4A-4F illustrates one process of applying a band to a
roll;
[0023] FIG. 5 is schematic of a bander described herein;
[0024] FIGS. 6A-6E illustrates a second process of applying a band
to a roll;
[0025] FIG. 7 is schematic of a bander including a diverter
described herein;
[0026] FIGS. 8A-8E are schematics of a liquid applicator described
herein;
[0027] FIG. 9 is schematic of a suction cup described herein;
and
[0028] FIG. 10 is schematic of a mandrel described herein
[0029] Before explaining at least one embodiment in detail it is to
be understood that the invention is not limited in its application
to the details of construction and the arrangement of the
components set forth in the following description or illustrated in
the drawings. The invention is capable of other embodiments or of
being practiced or carried out in various ways. Also, it is to be
understood that the phraseology and terminology employed herein is
for the purpose of description and should not be regarded as
limiting. Like reference numerals are used to indicate like
components.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] While the present disclosure will be illustrated with
reference to particular banders used with particular bag machines
and winders, it should be understood at the outset that the bander,
bag machine and winder can also be implemented with other designs,
and the bander can be implemented without the bag machine or
winder.
[0031] Generally, the bander described herein in includes multiple
banding stations. That allows each bander to operate at a lower
speed than the over all production rate of the bander. If there are
four banding stations, the speed of the bander will be four times
the speed of one station, for example. This allows the bander to
keep pace with the upstream source of rolls, even if the source is
a high speed bag machine and winder, such as a 600 fpm bag machine
and a winder with two 300 fpm winding stations.
[0032] Each banding station is preferably identical (except for
roll winding orientation) and includes a cradle for holding the
roll, and a band applicator for applying the band. The banding
station preferably includes at least one mandrel that holds the
roll, and the applicator preferably includes flexible fingers that
wrap the band about the roll. The band is preferably conveyed using
vacuum conveyors that helps wrap the band about the roll and
preferably include a source of air directed to the band that forces
the band into the cradle before the roll enters the cradle. The
band preferably includes glue that is activated when wetted. A
liquid applicator applies water to the band to activate the glue.
The liquid is preferably applied intermittently in the cross
direction (relative to the movement of the band), so that the dry
portions help provide stability for conveying the band.
[0033] FIG. 1 is a schematic of a machine 100 that includes a bag
machine 101, a winder 102, and a bander 103. Bag machine 101 forms
bags from a film, and is preferably a rotary bag machine such as
that shown in U.S. Pat. No. 5,377,929. The formed bags are provided
to winder 102 that is preferably like those described in U.S. Pat.
Nos. 8,029,428 7,578,779. The preferred embodiment provides that
winder 102 includes two winding stations 104 and 105. Alternatives
provide for 1 or more than two winding stations. Winder 102 is
preferably consistent with prior art winders, and can operate as
fast as bag machine 101. Bag machine 101 preferably operates at up
to 600 fpm, and produce about 240 side seal bags/minute. Forty
rolls of bags can be made in one minute in the preferred
embodiment.
[0034] After the rolls 108 are formed they are received by bander
103. Bander 103 includes a conveyor 110, and a plurality of banding
stations 112-114, each preferably 6-24 inches apart. There are
eight banding stations shown, although this embodiment includes
using only four banding stations. Either stations 112 are used (and
provided), or stations 114 are used (and provided), depending on
the direction each roll is wound. The number of stations shown is
merely exemplary. Alternatives provide more or fewer banding
stations. The formed rolls 108 are provided to conveyor 110.
Alternatives provide that a source of rolls other than a winder
and/or a bag machine are used. For example, the rolls could be
wound on one machine, and the banded on another, and the rolls can
be made at a nearby or distant location.
[0035] As rolls 108 move along conveyor 110 they are selectively
directed to one of the banding stations. A roll diverter (shown in
FIG. 7) diverts roll 108 off of conveyor 110 at the appropriate
location to direct roll 108 to a selected banding station. In one
embodiment roll 108 is pushed so that it rolls off conveyor 110. If
rolls are wound such that they would unroll when pushed to the
left, then banding stations 112a-112d are used. If the rolls are
wound such that they would unroll when pushed to the right, then
banding stations 114a-114d are used. The preferred embodiment
provides for the machine to have only one set 112 or 114 of banding
stations. Generally, if rolls 108 enter conveyor 110 from one side
the should be rolled back to that side. However, if a carousel is
sued by winder 102, then rolls 108 should generally be rolled off
to the opposite side they came from because the carousel flips the
rolls.
[0036] Diverting rolls in the selected direction reduces the
likelihood that the roll will roll unwind as its being diverted
into a banding station. Also, the diverter would preferably divert
rolls using a pattern such as 112a, 112c, 112d, 112b (and repeat)
to make sure that each banding station 112-114 has sufficient time
to complete the banding operation. The diverter includes mandrels
to hold the rolls, and/or paddles or ramps to direct the rolls in
various embodiments. One embodiment provides that rolls of bags can
be produced in 1.5 seconds (or 40/minute), and that banding
stations 122-114 can each operate at up to 10 rolls per minute.
Thus, the ratio of the winding speed (40/minute) to banding station
speed (10/minute) is 4. By providing 4 banding stations the bander
can keep pace with the winder (because the bander has four stations
at 10/minute and can collectively band 40/minute). Generally, it is
desirable to have at least as many banding stations as the ratio of
winder to banding station speed, so that the bander can keep pace
with the source of rolls.
[0037] FIG. 2 shows an embodiment of bander 103 used when winder
102 includes winding stations that wind rolls in opposite
directions. Rolls 108 are directed to one of winding stations
112a-112b or 114a-114b based on the winding direction (so that as
roll 108 rolls off of conveyor 110, the roll does not unroll).
Thus, as winding stations 104 and 105 alternately provide a
completed roll 108 to conveyor 110, the diverter would alternately
divert rolls to 112 and then 114. Also, the diverter would
preferably divert rolls using a pattern such as 112a, 114b, 112b,
114a (and repeat) to make sure that each banding station 112-114
has sufficient time to complete the banding operation. Bad rolls
are rejected off the end of conveyor 110 and are not banded.
[0038] Banding stations 112-114 and winding stations 104-105 are
vertically stacked, and/ or horizontally separated in various
embodiments.
[0039] FIG. 3 is a schematic of one banding station 112-114.
Banding stations 112-114 include a cradle 401 that holds a band 402
(and will hold a roll 108), fingers 404 and liquid applicators 405.
Fingers 404 are preferably articulated flexible fingers such as
Festo FinGripper.RTM. or SoftGripper.RTM.. Fingers 404 are used to
guide the ends of band 402 over roll 108 when roll 108 is in the
cradle. After a roll has been banded, a new band 402 is conveyed
(as described below) into cradle 401. Band 402 is conveyed from the
right, past liquid applicators 405. Liquid applicators 405 extend
in the cross direction (relative to the movement of band 402) and
apply liquid intermittently in the cross direction so that enough
glue on band 402 is activated to allow band 402 to secure to itself
when wrapped about roll 108. Preferably, enough of band 402 remains
dry that it is not too wet and floppy to convey to cradle 401 and
to wrap about roll 108. After band 402 is conveyed into cradle 401,
roll 108 (not shown in FIG. 3) is directed or diverted into cradle
401 over band 402. The ends of band 402 are wrapped about roll 108,
and secured to itself. Alternatives provide that the liquid applied
activate glues on band 402, or be glue itself.
[0040] FIG. 4 shows one banding procedure. FIG. 4A corresponds to
FIG. 3, but for clarity cradle 401 is omitted. Band 402 is conveyed
by vacuum conveyors 407 (suction cups, e.g.). An air source 409
blows air at band 402 so that band 402 conforms to cradle 401. FIG.
4B shows roll 108 placed over band 402. FIG. 4C shows fingers 404
moving the leading end of band 402 about roll 108. Suction cup 407
has positioned the tail end of band 108. FIG. 4D shows fingers 404
moving the trailing end of band 402 over the leading end of band
402. Suction cup 407 holds the tail end of band 108. FIG. 4E shows
fingers 404 that had been moving the leading end of band 402
withdrawn, and FIG. 4F shows fingers 404 completing the wrapping of
band 402 about roll 108.
[0041] Vacuum conveyors 407 of FIGS. 4 and 6 preferably are applied
to the paper band in a dry stripe (but this is not required). Three
vacuum cups and 4 articulating fingers are used in the preferred
embodiment to fold over, wrap, and hold one end of the sticky band
against the roll of bags until it stays in place by itself due to
the adhesive drying sufficiently. The process is repeated for the
other end of the paper band to create a finished banded roll of
plastic trash bags.
[0042] FIG. 5 shows an embodiment of bander 103 that has vertically
stacked banding stations. Two rolls of banding paper 501 and 502
provide the bands to each station, and each station includes a
cradle 401, such as that shown in FIG. 3 and operated as shown in
FIG. 4 Ramps 503A-503D have a roll 108 diverted thereto, and allow
roll 108 to roll into cradle 401. In practice only one ramp
503A-503D will receive a roll 108 at a given time. After banding
has been completed, ramps 503A-503D can be lowered to the dashed
position, and banded roll 108 can be dropped into a bin below the
ramps. Rolls 108 are provided to the ramps in the sequence of 503A,
503C, 503B, 503D, to avoid problems with nip timing.
[0043] FIG. 6 shows one banding procedure for another embodiment.
FIG. 6A shows vacuum conveyors 407, and liquid applicators 405.
Band 402 is shown conveyed by vacuum conveyors 407 in FIG. 6B, and
air source 409 blows air at band 402 so that band 402 conforms to
cradle 401. FIG. 6C shows roll 108 placed over band 402, having
reached cradle 401 via ramp 503. FIG. 6D shows roll 108 being
unwound so that the tail end of roll 108 maybe straightened (for
better banding). The roll is then wound straight and tight and in
FIG. 6E the band is wound about roll 108 and about itself. A
mandrel such as that described below with reference to FIG. 10 is
preferably used for unwinding and rewinding the roll.
[0044] FIG. 7 shows another embodiment of bander 103 that includes
four banding stations 701A-701D. The design of each banding station
701A-701D is preferably a design shown in FIG. 4 or 6, but can be a
different design. A roll diverter 705 is shown that diverts rolls
108 to the desired and selected banding station. Diverter 705
receives rolls from winding stations 104 and 105. Diverter 705 is
shown in four positions, each corresponding to diverting roll 108
to one banding station. When diverter is in position 705A, roll 108
is diverted to banding station 701A. When diverter is in position
705B, roll 108 is diverted to banding station 701B. When diverter
is in position 705C, roll 108 is diverted to banding station 701C.
When diverter is in position 705D, roll 108 is diverted to banding
station 701D. Other diverters may be used, and for a horizontal
conveyor diverter 705 may be a simple design that pushes roll
108.
[0045] Liquid applicators 405 (FIGS. 3, 4, 6) are shown in more
detail in FIG. 8, and preferably apply water in stripes (so that a
cross direction profile alternates between wet areas 803 and dry
areas 805. The striped pattern to give the paper band extra
strength and robustness which is helpful in the downstream banding
operations. Applicators 405 spray water onto band 402. The band
typically has a low cost water activated adhesive, similar to a
postage stamp of old. The water can be sprayed in any direction
desired and can be sprayed in multiple spots (thus creating stripes
of sticky areas) as the paper band travels past. A fine mist in a
0.25''-1.0'' pattern is preferred. One preferred spraying system
uses a pressurized water tank such as available from Spraying
Systems Company in Wheaton Ill. A 0.25''-2.0'' space of no water
between wet stripes is desirable. This pattern improves the process
by: increasing the paper tear strength, increasing paper bridge
strength as it is pushed over unsupported gaps, reducing paper curl
due to water/glue activation; maintains a flatter paper shape when
wet, creating a wider operating window for the amount of water
applied because excess water is absorbed later in the process at
the dry stripes, allowing a dry area for guide fingers to be used
without sticking to adhesive, reducing wrinkling which improves the
aesthetics of the advertising label/band, and improving the end
users ability to pick off the paper band so they can use the bags.
After the water mist is sprayed on it is then wiped with a wiper or
brush 801 to force the water into micro droplets and adhere better
to the surface texture of the adhesive. A wiper can be created by
many means such as: horse hair bristle brush with tapered cut tip;
plastic sheet; rubber sheet; metal sheet; or by blowing air to act
as a wiper. Adding heat to the water can improve the water wiping
characteristics. Adding a chemical agent to the water can improve
the water wiping characteristics.
[0046] Alternatives are shown in FIGS. 8B-8E. FIG. 8B shows
applicators 405 implemented with brushes attached to a water source
810 (or other source of liquid). The amount of liquid applied is
preferably metered, such as by using flow limiter FIG. 8C shows
rollers implementing applicators 405. The gap between rollers 405
determines the width of the dry areas and can be adjusted as
desired. FIG. 8D shows applicators 405 implemented with sponges and
FIG. 8E shows rollers 405 receiving water from an adjustable source
820 (having High, Medium and Low settings).
[0047] FIG. 9 is one embodiment of suction cup or suction conveyor
407. It can be a suction cup from Piab, F20 Silicone, G1/8'' male,
with mesh filter. Multiple conveyors 407 are preferably used to
convey band 402.
[0048] FIG. 10 shows a chuck or mandrel 1001 used to hold roll of
bags 108 while banding or to divert roll 108 to the banding
position. The mandrel can be used in conjuction with or instead of
the cradle and/or diverter described above. The preferred shape for
mandrel 1001 for a roll from a one inch diameter winding spindle is
approximately 0.25'' radius to 0.5'' radius semi-circle. That
radius can be extended outward on the tip of a cylindrical shape so
the resulting protrusion is 0.5''to 1.0'' long. An alternative
includes adding a cone shape or taper. The mandrel should hold
rolls tight and concentrically without damaging or crushing the
roll of bags, preferably to grips the film to assist with
re-winding the roll extra tight before banding begins. The
preferred material is a 40-80 durometer rubber-like material. Other
embodiments use silicone, nitrile, etc. The preferred embodiment
includes a secondary shape on which the mandrel is mounted,
including a shoulder for the roll to butt up against. The shoulder
size preferably allows a sufficient grip on the roll without
getting in the way of the band application. The shoulder diameter
is preferably is about 1.25'' for winding small count rolls that
are 1.50'' in diameter. For larger count rolls the shoulder
diameter is preferably 0.25'' smaller than the roll. To prevent
loose film from getting captured between the mandrel and the roll
end it the shoulder starts tapering away from the roll end for
large diameter rolls.
[0049] The tail straightening shown in FIG. 6D can be performed
using two of the mandrels to grab the roll from each end after the
roll is dropped into the semi-circle like cradle or cavity. Once
the roll is securely held by extending the mandrels the cradle can
be opened or backed away from the roll. An air curtain (preferable
an ARTX brand venturi style) located 0.06''-0.75'' from the roll
surface is used to blow the outer bag tail in a desired direction.
The roll is turned and unwound 1-3 revolutions via the mandrels.
This allows any disturbed or wrinkled or telescoped tails to
straighten out in the air stream. The mandrels then re-wind the
tail straight and true. Applying slight tension (1/8-1 pound of
drag force) on the tail improves the final re-wind so it is as
tight as possible. Having a tight wind also improves the ability to
band tightly. The semi-circular cradle can apply the desired drag
force.
[0050] Numerous modifications may be made to the present disclosure
which still fall within the intended scope hereof. Thus, it should
be apparent that there has been provided a method and apparatus for
banding rolls of bags that fully satisfies the objectives and
advantages set forth above. Although the disclosure has been
described specific embodiments thereof, it is evident that many
alternatives, modifications and variations will be apparent to
those skilled in the art. Accordingly, the invention is intended to
embrace all such alternatives, modifications and variations that
fall within the spirit and broad scope of the appended claims.
* * * * *