Note: Descriptions are shown in the official language in which they were submitted.
CA 02693873 2010-02-22
ROTARY CUTTING DIE APPARATUS FOR CUTTING CORRUGATED BOARD
INCLUDING RETAINERS FOR MAINTAINING TRIM STRIPPERS CLOSELY
ADJACENT TRIM CUTTING BLADES
FIELD OF THE INVENTION
[0001] The present invention relates to rotary cutting dies for cutting and
scoring
corrugated board, and more particularly to a rotary cutting die having trim
cutting blades
and trim strippers for engaging cut pieces of trim and directing them away
from the rotary
cutting die.
BACKGROUND OF THE INVENTION
[0002] Rotary cutting dies are commonly used for producing a container or
carton
blank from corrugated board sheet material. Such rotary dies are typically
comprised of a
die cylinder, a die board mounted on the die cylinder and including cutting
blades and
scoring rules, and an anvil mounted adjacently the die cylinder and the die
board. A nip is
defined between the die board and the anvil and sheets of corrugated board are
fed into
the nip. As the corrugated board is fed through the nip, the cutting rules,
scoring rules
and other devices and elements mounted on the die board engage and operate on
the
corrugated board passing through the nip and between the die board and the
anvil.
[0003] Most die boards are designed to trim the corrugated board along
surrounding
edges as the corrugated board passes through the nip. To accomplish this, the
die board
is provided with a series of trim cutting blades. Also mounted to the die
board adjacent
the outside of the respective trim cutting blades is elastomer trim transfer
devices or trim
strippers. The trim strippers are compressible and resilient. During the trim
cutting
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process, the trim strippers engage the cut pieces of trim as they pass through
the nip and
hold the cut pieces of trim against the anvil for a short period of time. The
trim strippers
function to separate the cut pieces of trim from the resulting product board.
[0004] Over a period of time, the trim strippers or trim transfer devices tend
to
separate and move away from the adjacent trim cutting blades. That is, as the
trim
strippers are compressed and passed through the nip, it is common to find that
they tend
to bow and as they bow, a small gap occurs between the trip strippers and the
adjacent
trim cutting blades. Once this gap occurs, it is common for small pieces of
cut trim to
become lodged or packed in the gap. Over a period of time, this cut trim
becomes more
compact and is effectively driven down between the trim strippers and the trim
cutting
blades. The forces placed on the cut pieces of trim can be so great that they
damage
and even break the die board.
SUMMARY OF THE INVENTION
[0005] The present invention relates to a rotary cutting die that is adapted
to be
mounted on a rotary die cylinder for cutting corrugated board fed between the
cutting die
and an anvil. The rotary cutting die includes a die board and a plurality of
trim cutting
blades mounted on the die board. Trim strippers or trim transfer devices are
secured on
the die board adjacent the trim cutting blades and functions to engage cut
pieces of trim
and urge the cut pieces of trim away from the trim cutting blades. A retainer
is mounted
on the die board closely adjacent the trim strippers such that the trim
strippers are
confined and disposed between the retainer and the trim cutting blades. By
confining the
trim strippers between the retainer and trim cutting blades, the trim
strippers are
maintained closely adjacent the trim cutting blades such that a gap does not
occur
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between the trim strippers and the trim cutting blades. This generally
prevents cut pieces
of trim from becoming jammed or packed between the trim strippers and the trim
cutting
blades.
[0006] In another embodiment of the present invention, there is provided a
preloading
device mounted on the die board ahead of a leading trim cutting blade. The
preloading
device engages the anvil during the process of trimming and cutting corrugated
board
and preloads the rotary die cylinder that the die board is mounted on prior to
the leading
trim cutting blade loading the die cylinder. This preloading device tends to
gradually load
the die cylinder as opposed to abruptly loading the die cylinder which may
occur when the
leading trim cutting blades engage the corrugated board. By gradually loading
or
preloading the die cylinder as contrasted with abruptly loading, upstream
printing
operations are made more efficient and generally typical problems associated
with ink
smudging is avoided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 is a perspective view of a rotary cutting die apparatus
showing trim
cutting blades, trip strippers and retainers for maintaining the trim
strippers in close
proximity to the trim cutting blades.
[0008] Figure 2 is a fragmentary perspective view showing a portion of a die
board of
the present invention.
[0009] Figure 2A is an exploded view showing portions of the trim cutting
blades, trim
stripper and retainer.
[0010] Figure 3 is a fragmentary perspective view showing another portion of
the die
board of the present invention.
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[0011] Figure 4 is a fragmentary plan view showing a portion of the die board
of the
present invention.
[0012] Figure 5 is a sectional view taken through the line V-V of Figure 4.
[0013] Figure 6 is a sectional view similar to Figure 5, but showing a block
of wood
used as the retainer.
[0014] Figure 7 is a fragmentary sectional view showing an alternative design
for a
trim stripper.
[0015] Figure 8 is a fragmentary sectional view showing another alternative
design for
a trim stripper.
[0016] Figure 9 is fragmentary sectional view showing still another
alternative design
for the trim stripper.
[0017] Figure 10 is a schematic illustration of a portion of a die board
including a
preloading device.
[0018] Figure 11 is a fragmentary sectional view taken through the line XI-XI
of Figure
10.
[0019] Figure 12A is a schematic illustration showing a trim stripper
beginning to pass
through the nip between a die board cylinder and an anvil cylinder.
[0020] Figure 12B is a schematic illustration showing the continued movement
of the
trim stripper through the nip and showing the trim stripper engaging a piece
of cut trim.
[0021] Figure 12C is similar to Figures 12A and 12B and which shows the trim
stripper
exiting the nip, but still engaged with the cut piece of trim.
[0022] Figure 13 is a schematic illustration of a machine that includes the
rotary
cutting die assembly along with a series of printing stations.
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DETAILED DESCRIPTION
[0023] With further reference to the drawings, a rotary cutting die apparatus
is shown
therein and indicated generally by the numeral 30. As is appreciated by those
skilled in
the art, the rotary cutting die apparatus 30 is designed to receive sheets of
corrugated
board CB and to trim the sheets of corrugated board to yield a product board.
Further,
the rotary cutting die apparatus 30 is designed to cut, score, and in some
cases remove
scrap from areas of product board. In the end, the rotary cutting die
apparatus 30 is
designed to treat and condition the corrugated board such that when the
corrugated
board exits the rotary cutting die apparatus, the product board can be easily
manipulated
into a box configuration.
[0024] With reference to Figure 1, the rotary cutting die apparatus 30
includes a die
board cylinder 40 and an anvil cylinder 50. As will be appreciated from
subsequent
portions of the disclosure, the die board cylinder 40 is designed to receive
and hold a die
board 42. The die board cylinder 40 including the die board 42 is disposed
with respect
to the anvil cylinder 50 such that a nip is defined there between. As sheets
of corrugated
board are fed through the nip, corrugated board is engaged by the die board 42
which
trims, cuts and scores the corrugated board. The anvil cylinder 50 is
typically surrounded
or sheathed with a surface layer or coating 52 of a relatively compliant
material such as
urethane, which provides a backing surface against which a cut can be made
without
damaging various components carried by the die board 42. As such, anvil
cylinder 50
rotates in a manner that is generally synchronous with the adjacent die board
cylinder 40
during normal operations.
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[0025] Die board 42 is typically constructed of laminated plywood. Die boards,
such
as that illustrated in Figure 1, typically include a combination of cutting
blades, creasing
rules, resilient scrap strippers, resilient product ejectors and the like.
[0026] More particularly, the die board 42 includes a series of trim cutting
blades 44
which are securely mounted in the die board such that the cutting tips of the
blades 44
protrude and extend generally outwardly and away from the surface of the die
board
cylinder 40. Trim cutting blades 44 extend generally around an area of the die
board 42.
For example, the trim cutting blades 44 include one or more leading trim
cutting blades
such as shown in Figures 2 and 12A, one or more side trim cutting blades such
as
appears in Figure 3 and one or more trailing trim cut blades that are shown
extending
transversely across the lower portion of the die board 42 in Figure 1. Each
trim cutting
blade 44 includes an outboard side that is referred to by 44A and an inboard
side that is
referred to by 44B.
[0027] Rotary cutting die apparatus 30 is designed to receive the corrugated
board
CB. As the corrugated board CB passes through the nip, the die cutting board
and the
elements thereof is effective to trim the corrugated board. That is, the trim
cutting blades
44 trim small trim pieces TP from the outside edge of the corrugated board.
This leaves a
product board or a product portion of the corrugated board. Die board 42 and
the
elements thereon operate on the product portion to cut and score and form the
product
board into a corrugated panel that can be shaped and formed into a corrugated
box or
container.
[0028] The term "trim cutting blade" or "trim blade" is specifically defined
as a blade
that trims the corrugated board CB and cuts a piece of trim from around edge
portions of
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the corrugated board to leave the finished die cut product. The term "trim
cutting blade"
or "trim blade" specifically excludes any scrap cutting blades located within
the area
defined by the overall length and overall width of the finished die cut
product.
[0029] Disposed adjacent trim cutting blades 44 is a series of trim strippers
46. In
some cases, the trim strippers 46 are referred to as elastomer trim transfer
devices. The
trim strippers 46 are positioned adjacent the outboard side 44A of the trim
cutting blades
44. They function to engage the cut trim pieces TP cut from the corrugated
board CB by
the trim cutting blades 44 and direct the cut trim pieces away from the trim
cutting blades
and away from the product portion of the corrugated board CB. Trim strippers
46 can
assume various shapes. In the embodiment illustrated herein, the trim
strippers 46 are
generally elongated and are generally rectangular or square in cross section.
The trim
strippers 46 are resilient and compressible and are typically manufactured
from a resilient
material such as a urethane having a durometer of 85 on a Shore 00 scale and
having a
density of approximately 45 g/cm3.
[0030] For purposes of explanation, each trim stripper 46 includes an outboard
side
46A and an inboard side 46B. Inboard side 46B is set directly adjacent the
outboard side
44A of a trim cutting blade 44. This is true for all of the trim cutting
blades 44 irrespective
of their location on the die board 42. That is, in the case of the leading
trim cutting blade
(Figure 2), the trim stripper or strippers 46 is disposed directly adjacent
the outboard side
44A of the trim cutting blade 44. Likewise, for side and trailing trim cutting
blades, the trim
strippers 46 are disposed on the outside thereof such that the inboard side
46B of the trim
strippers engage and rest against the outboard side 44A of the trim cutting
blades.
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[0031] As discussed above, in conventional rotary cutting dies there is a
tendency for
the trim strippers to bow. That is, as the die board rotates and the trim
strippers engage
cut trim as well as the anvil, the trim strippers tend to bow, leaving a gap
between the trim
strippers and the outboard side of the trim cutting blades. This results in
the inboard side
of the trim stripper moving away from the adjacent trim cutting blade. Often,
this leaves
the gap between the trim cutting blade and the trim stripper. Over a period of
time, small
cut pieces of trim tend to wedge themselves between the trim cutting blade and
the
adjacent trim stripper. This over time causes substantial forces to be applied
against the
blade and ultimately the die board, often resulting in damage to the die
board.
[0032] In addition to the trim strippers 46 just discussed, also provided are
secondary
trim strippers 48. As illustrated in Figure 4, the secondary trim strippers 48
are disposed
outside the trim cutting blades 44. Secondary trim strippers 48 can be placed
at various
locations on the die board 42. In general, as illustrated in Figure 4, the
secondary trim
strippers 48 are disposed outside of the trim cutting blades 44 and as
illustrated in Figure
4 in this one example the secondary trim strippers 48 include a series of
generally U-
shaped trim strippers disposed along the side of the die board and three
secondary trim
strippers disposed in the leading corners of the die board just outwardly of
the trim cutting
blades 44. The secondary trim strippers 48 may be placed along the leading
edge of the
die board 42, just outwardly of the leading trim cutting blades 44 and the
primary trim
strippers 46. Generally, the secondary trim strippers 48 are optional.
Secondary trim
strippers 48 may be useful during the set up and initial runs of the rotary
cutting die
apparatus 30. In some cases during set up and initial runs the leading trim
pieces cut
may be larger than would ordinarily occur during normal operations. In these
cases, the
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secondary trim strippers 48 engage the relatively large pieces of cut trim and
urge them
downwardly in engagement with the anvil 50 and cause the cut trim pieces to be
separated from the produced product board. For the secondary trim strippers
48,
conventional trim stripping material can be used. In one embodiment it is
contemplated
that the material used for the secondary trim strippers 48 would be less dense
than the
material used for trim strippers 46.
[0033] The present invention provides a retainer 100 for engaging the trim
strippers 46
and maintaining the trim strippers closely adjacent the trim cutting blades 44
so that the
tendency for a gap to occur between the trim strippers and the trim cutting
blades is
reduced or eliminated. Therefore, as seen in the drawings, a series of
retainers 100 is
mounted in the die board outside of the trim cutting blades 44 and outside of
the trim
strippers 46. As seen in the drawings, the retainers are spaced so as to
closely confine
the trim strippers 46 between the trim cutting blades 44 and the retainers
100. The
retainers 100 include an outboard side 100A and an inboard side 100B. The
retainers
100 are positioned flush against the outboard side 46A of the trim strippers
46. The
purpose of the retainers 100 is to hold the trim strippers 46 closely adjacent
the outboard
side of the trim cutting blades 44. This confines the trim strippers 46
between the trim
cutting blades 44 and the retainers 100. This prevents the trim strippers 46
from bowing
and leaving a gap between the trim strippers and the trim cutting blades 44.
[0034] Retainers 100 can take various forms. In one embodiment, the retainers
comprise a series of scoring or cutting rules mounted in the die board 42. In
another
embodiment, the retainer 100 can assume the form of a block object secured on
the die
board 42. For example, the block object could be surface mounted to the die
board 42.
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In one particular example, the retainer is a block of wood that is stapled,
glued or
otherwise fastened to the die board 42. This is illustrated in Figure 6 and
the block of
wood is indicated at 1000. Discussed subsequently herein are preloading
devices 150.
The preloading device subsequently discussed herein could be utilized as a
retainer for
retaining the trim strippers 46 in a space defined generally between the trim
cutting
blades 44 and the preloading devices. Other forms and types of retainers may
be used.
The retainers 100 should be sufficiently strong enough and of a height to
retain the trim
strippers 46 and maintain the trim strippers closely adjacent the respective
trim cutting
blades 44.
[0035] As pointed out above, the trim stripper 46 can assume various designs.
A few
exemplary designs for the trim stripper 46 are shown in Figures 7, 8 and 9.
First, in
Figure 7, the trim stripper shown therein is still confined between the trim
cutting blade 44
and the retainer 100. In this case the trim stripper includes a member 46C
that can be an
elastomer constructed of foam, rubber, or the like. Secured by glue or other
suitable
fastening means to member 46C is a cap 46D. The cap 46D assumes an inverted U-
shape and includes downwardly extending sides that are confined between the
retainer
100 and the trim cutting blade 44. As viewed in Figure 7, the resilient member
46C is
compressible as it passes through the nip. Cap 46D, which can be constructed
of plastic
or other suitable materials, moves with the compressible member 46C.
Consequently,
both member 46C and cap 46D move back and forth between the retainer 100 and
trim
cutting blade 44 as the trim stripper passes through the nip.
[0036] Figure 8 is another example of a trim stripper design. Here the trim
stripper 46
includes a resilient member 46E that is confined between retainer 100 and trim
cutting
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blade 44. Again, member 46E can be an elastomer such as a resilient block
constructed
of rubber, foam or the like. Secured to the top of member 46E is a cap 46F.
Cap 46F
includes a resilient wiper 46G that extends from one side of the cap 46F. The
wiper 46G
is biased to generally engage the trim blade 44 as the trim stripper is moved
back and
forth within the confines of the retainer 100 and trim blade 44. Wiper 46G by
engaging
the outboard surface of the trim cutting blade 44 prevents cut trim from being
lodged
between the wiper 46G and the outboard side of the trim cutting blade 44.
[0037] Figure 9 is another exemplary trim stripper. Here the trim stripper
includes a
resilient member 46H in the form of a spring. The spring is seated on the die
board 42
and extends therefrom. Secured over the spring 46H is a cap 461. Cap 461
assumes an
inverted U-shape with the sides thereof extending, as viewed in Figure 9,
downwardly
between the spring 46H and the retainer 100 and trim cutting blade 44. Again,
as the trim
stripper passes through the nip, the resilient member or spring 46H is
compressed
causing the cap 461, as viewed in Figure 9, to move downwardly. Again, the
retainer 100
and trim cutting blade 44 confine the cap 461. The retainer 100 functions to
retain the cap
461 closely adjacent the outboard side of the cutting blade 44 such that cut
trim is not
packed or wedged between the cap 461 and the outboard side of the trim cutting
blade
44.
[0038] Which further reference to the drawings, the die board 42 includes
other
elements that are associated with the trim cutting blades 44. For example,
extending
perpendicularly outwardly from the outboard side 44A of the trim cutting
blades 44 is a
series of trim breakers 120. Many of the trim breakers disclosed herein assume
a
generally L-shape on the die board 42. They may also be generally straight.
The trim
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breakers 100 include an upper cutting edge that is effective to cut the
outside trim pieces
into smaller portions. Note that the trim breakers 120 generally extend from
or even abut
the trim cutting blades 44.
[0039] The trim cutting blades are also reinforced by a series of rule
supports 130.
Note in Figures 2 and 4 where the rule supports lie adjacent the inboard side
44B of the
cutting blades 44. These rule supports 130 extend into or abut against the
inboard side of
the cutting blades 44 so as to support and reinforce the trim cutting blades.
[0040] Turning to Figure 10 of the drawings, there is shown therein a machine
for
printing and die cutting corrugated board. The machine is referred to
generally by the
numeral 200. The machine 200, in this embodiment, includes three basic
operating
stations. Station 210 is a first print station and 212 refers to a second
print station.
Located downstream from the second print station 212 is a die cutting station
indicated
generally by the numeral 214. Die cutting station 214 includes the rotary die
cutting
apparatus 30 discussed above. That is, die cutting station 214 includes the
rotary die
cylinder 40, anvil cylinder 50 and die board 42. Upstream from the first print
station 214 is
a pair of rollers 202, 204. Roller 204 is driven by a motor that is controlled
through a
controller. Roller 204 has a gear associated therewith that is effective to
drive the
components of the first print station. The first print station 210 includes a
gear network
that is operative to drive the second print station which likewise has a gear
network that is
operative to drive the die cutting station 214. Details of the machine 10 will
not be dealt
with herein because such is not per se material to the present invention and
further such
machines are known. Suffice to say that corrugated board CB is fed into the
machine
from right to left, as viewed in Figure 10. The corrugated board is fed into
the nip
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between rollers 202 and 204 and continues generally horizontally through the
first and
second print stations 210 and 212 and then through the die cutting station
214. In the
process, printing plates carried by the print rollers of the first and second
print stations
210 and 212 are operative to print indicia, designs, etc. on the passing
corrugated board.
Once the corrugated board clears the second print station 212, it enters the
die cutting
station 214 and the die board 42 and the elements thereon trim the corrugated
board and
further cut and act on the remaining product board.
[0041] In the example shown in Figure 10, each station 210, 212 and 214
includes a
dedicated motor for assisting and powering the respective stations. However,
in many of
the machines similar to that shown in Figure 10, the multiple stations are
powered by a
single motor that drives an initial roller such as roller 204 at the inlet end
of the machine.
In this case particularly, the printing process is sometimes encumbered by
abrupt loads
that are repeatedly placed on the components of the die cutting station 214.
In particular,
when the leading trim cutting blade comes into contact with the corrugated
board, there is
an abrupt load placed on the rotary die cylinder 40. This for just a moment
causes a
hesitation in the upstream drive system. This hesitation is just enough to
cause a small
ink smudge at a particular point or area on the corrugated board.
[0042] The present invention entails a die board that is designed to avoid the
abrupt
loads caused by the leading trim blades on each revolution of the rotary die
cylinder 40.
[0043] The present invention entails one or more preloading devices, indicated
generally by the numeral 150 mounted on the die board 42 just ahead of the
leading trim
cutting blades 44. Essentially the preloading devices 150 provide a gradual
load to the
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rotary die cutting apparatus 30 prior to the leading trim cutting blades 44
engaging the
corrugated board and cutting the trim against the anvil 50.
[0044] The preloading devices can be designed and arranged in various ways. In
the
present application, each preloading device includes one or more ramps that
are aligned
with the leading trim cutting blades 44 and spaced ahead of the trim cutting
blades. That
is, as seen in Figure 2, 4, 6 and 7, the preloading devices 150 include a ramp-
like
structure that is inclined such that the upper surfaces of the ramps are
inclined outwardly
from the die board 42 in the general direction of the leading trim cutting
blades 44.
[0045] In the case of the embodiment shown in Figure 2, the preloading devices
are in
the form of a compressible ramp structure that is made of urethane or hard or
semi-hard
rubber. Various materials can be used for the ramps. In one embodiment the
preloading
ramp, such as shown in Figure 2, comprises a urethane generally described as
Shore A,
durometer 85-87. These ramps include side edges and an upper inclined surface.
Note
that as viewed in Figure 2, the upper inclined surface of each preloading
device is inclined
upwardly in the direction of the leading trim cutting blades 44. Thus, on each
revolution of
the rotary die cylinder 40, these ramps or preloading devices 150 will engage
the anvil 50
ahead of the leading trim cutting blades 44 so as to gradually load the rotary
die board
cylinder 40. This gradual loading of the cylinder 40 will prevent abrupt
loading and will
reduce the tendency of the printing stations to cause ink smudges
instantaneously at the
time of abrupt loading.
[0046] The preloading ramps can assume various forms. In an alternative design
shown in Figure 7, the preloading device 150 includes a series of upstanding
elements
154. This is referred to as a segmented ramp because it is not continuous or
does not
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include a continuous upper surface. Various types of elements can be employed.
In one
embodiment, the various elements comprising the preloading device in Figures 6
and 7 is
a series of scoring rules with their heights varying. As viewed in Figures 6
and 7, the
height of the respective elements of the segmented ramp, generally become
taller or
higher towards the retainer 100 and trim stripper 46. Again, the elements that
make up
the segmented ramp shown in Figures 6 and 7 will effectively gradually preload
the die
board cylinder 40. In some cases, the various elements of the segmented ramp
can be
turned 90 or at other angles from that shown in Figures 6 and 7. The length
of the
respective segments can vary.
[0047] Figures 9A, 9B and 9C are a sequence of views showing how the retainer
100
confines the trim stripper 46 and prevents a gap from occurring between this
trim stripper
and a trim cutting blade 44. Further, the sequence of drawings illustrates how
the
preloading device 150 preloads the die board cylinder 40 to prevent abrupt
loading.
[0048] In Figure 9A, the corrugated board is fed into the nip and at the point
shown
therein, the trim cutting blade is disposed at a point where it is about to
engage the
corrugated board CB and cut a piece of trim from the leading edge of the
corrugated
board. At this point, a portion of the trim stripper 46 has engaged the trim
piece and has
been partially compressed.
[0049] In Figure 9B the trim cutting blade 44 has severed the trim piece and
the trim
piece is held against the surface of the anvil 50 by the trim stripper 46.
Note that the
retainer 100 has confined the trim stripper 46 between the retainer and the
trim cutting
blade 44 such that a gap does not appear between the trim stripper and the
trim cutting
CA 02693873 2010-02-22
blade. Thus, the piece of cut trim cannot be wedged between the trim stripper
46 and the
trim cutting blade 44.
[0050] Figure 9C shows a continuation of the process where the trim stripper
46
remains engaged with the cut piece of trim TP and is holding the cut piece of
trim against
the surface of the anvil 50 so as to separate the trim from the following
product board. As
the process continues, the trim stripper 46 will continue to hold the cut
piece of trim
against the surface of the anvil until it is released. At the point of the
release, the cut trim
TP is at a position where the anvil will tend to direct the cut piece of trim
downwardly and
to the left as viewed in Figure 9C. This separates the cut trim from the
product board.
This same process occurs around the die board 42 and around the various
cutting blades
44 utilized. The trim strippers 44 are maintained closely adjacent trim
cutting blades 44
such that pieces of trim cannot be wedged or jammed into an opening or gap
that occurs
between the trim stripper 46 and the trim cutting blades 44.
[0051] There are many advantages to the die board 42 of the present invention.
The
use of the retainers 100 to confine the trim strippers 46 between the trim
cutting blades 44
and the retainers generally preclude cut trim pieces from being wedged and
packed
between the trim cutting blades and the trim strippers. In addition, with the
retainers 100,
taller and firmer stripping material can be employed along the leading edge of
the die
board. This provides better separation of cut trim pieces from the product
board, and as a
result less trim pieces end up with the product.
[0052] The present invention may, of course, be carried out in other ways than
those
specifically set forth herein without departing from essential characteristics
of the
invention. The present embodiments are to be considered in all respects as
illustrative
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and not restrictive, and all changes coming within the meaning and equivalency
range of
the appended claims are intended to be embraced therein.
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