U.S. patent number 3,866,497 [Application Number 05/309,128] was granted by the patent office on 1975-02-18 for cross-perforating of continuously moving, superimposed leaves.
Invention is credited to John Harper, Larry B. Wolfberg.
United States Patent |
3,866,497 |
Wolfberg , et al. |
February 18, 1975 |
Cross-perforating of continuously moving, superimposed leaves
Abstract
A method and apparatus of producing continuous,
cross-perforated, snap-out business forms and the like consisting
of a plurality of properly aligned, superimposed sheets in which
the interval between cross-perforation lines may be varied with a
minimum of "down-time" to provide business forms of diverse sizes
while maintaining a uniform fold interval for stacking the
continuous sheets one on top of the other into a pack.
Inventors: |
Wolfberg; Larry B. (Wichita,
KS), Harper; John (Wichita, KS) |
Family
ID: |
26904832 |
Appl.
No.: |
05/309,128 |
Filed: |
November 24, 1972 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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210124 |
Dec 20, 1971 |
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882256 |
Dec 4, 1969 |
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Current U.S.
Class: |
83/30; 83/343;
83/331; 83/346; 270/37; 493/410; 270/52.07; 83/37; 83/678;
493/399 |
Current CPC
Class: |
B26F
1/20 (20130101); Y10T 83/4795 (20150401); Y10T
83/4838 (20150401); Y10T 83/9408 (20150401); Y10T
83/483 (20150401); Y10T 83/0515 (20150401); Y10T
83/0481 (20150401) |
Current International
Class: |
B26F
1/00 (20060101); B26F 1/20 (20060101); B26f
001/08 () |
Field of
Search: |
;83/1,37,30,13,678,300,303,284,331,299,343,346 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Schran; Donald R.
Attorney, Agent or Firm: Schmidt, Johnson, Hovey &
Williams
Parent Case Text
CROSS-REFERENCES
This is a continuation-in-part of our copending application Ser.
No. 210,124, filed Dec. 20, 1971, and entitled "Glue Fastening Of
Superimposed Leaves", said copending application itself being a
continuation of prior copending application by the same title, Ser.
No. 882,256, filed Dec. 4, 1969, now abandoned.
Claims
Having thus described the invention, what is claimed as new and
desired to
1. In a method of preparing a cross-perforated, multi-leaved web
foldable in opposite directions at preselected perforation fold
line intervals for formation of a layered pack having, in each
layer, a plurality of end-to-end articles separated by perforation
tear lines, the steps of:
advancing a plurality of leaves in superimposed, aligned
relationship with one another along a common path of travel;
presenting the advancing web of leaves to a first perforating
station;
producing spaced-apart, perforation fold lines in the advancing
leaves at said first station by alternately penetrating the leaves
from opposite directions at preselected intervals;
presenting the advancing web of leaves to a second perforating
station independent of said first station; and
producing spaced-apart, perforation tear lines in the advancing web
of leaves at said second station and at preselected intervals
selected to locate at least one perforation tear line between each
pair of perforation
2. In a method as claimed in claim 1, wherein the step of producing
tear
3. In a method as claimed in claim 1, wherein said step of
producing tear lines includes penetrating the leaves from one
direction only for all of
4. In a method as claimed in claim 1, wherein is included the step
of varying the spacing between said tear lines produced at said
second station while maintaining the spacing between fold lines
produced at said
5. In a method as claimed in claim 1, wherein said tear lines are
produced at said second station by a rotating member having at
least one elongated set of peripherally disposed, leaf-penetrating
means, and wherein is included the step of varying the number of
said tear lines between each pair of fold lines by changing the
number of sets of said penetrating
6. In a method as claimed in claim 1, wherein said stations are
provided with cylindrical, rotating members having peripherally
disposed, elongated sets of leaf-penetrating means, and wherein is
included the step of changing the spacing between the fold lines
and between the tear lines by substituting members of one diameter
for those of another diameter.
Description
In the manufacture of continuous business forms and the like it is
extremely important that they be capable of use in automatic,
computerized printers and other machines without creating any
difficulty such as jamming, damage to the forms, malfunction of the
machines or other problems. This necessitates high perfection in
the production of the multilayered units whether in the nature of
sheets or leaves used as business forms, stationery or
otherwise.
By far the most difficult problem is in the line gluing of the
sheets together. First of all, there must not be any undue
bulkiness at the zone of the glue line. Secondly, the increase in
thickness necessitated by the presence of the glue must be uniform
and minimal. Thirdly, the glue line must be continuous in absence
of spaces therealong where complete interconnection of the sheets
cannot be effected. Fourthly, the interconnection must not give way
and permit separation of the sheets at any point along the glue
line either during production, or during storage and shipment, or
during use in printing machines or other equipment.
Convenionally, both the so-called hot and cold glues have been used
for this purpose, including both animal and dextrin solutions. And
various heating methods have been tried, including infrared thermal
radiation to evaporate the liquid content of the glue and to,
therefore, effect drying. But, except in cases of rather expensive,
slow procedures, no prior method has been entirely successful
regardless of the type of glue or heating methods employed.
Particularly aggravating has been the problem known as "tenting"
and the problem of build-up bulk caused by the line of glue. The
continuous, multicopy sheets to which the present invention relates
are folded transversely at equally spaced intervals to presnet a
finished pack which cannot only be conveniently stored and shipped
but which will automatically unfold as the same is fed to
computerized printers, typewriters and other machines. Defective
gluing results in separation of the sheets at each line of fold,
forming a small triangular bulge known as a "tent". Such condition
cannot be tolerated primarily because of malfunction in the
aforementioned machines with which the forms and the like are
ultimately used.
Still another problem in the assembly and fastening of a number of
continuous leaves of paper for use as above explained relates to
maintaining the sheets in proper alignment. Consequently, each
layer must be rather perfectly aligned, edgeto-edge, with proximal
sheets thereabove and therebelow so that all material printed or
typed on the original will be reproduced on the copies, by the
effect of interleaved carbon, mechanical or chemical self-contained
reproducing paper, in substantially the same location marginally as
well as top to bottom. Conventional methods of assembly and
interconnection of such continuous, superimposed leaves or sheets
of paper through use of glue have not always solved this problem to
the complete satisfaction of all users.
An additional problem in the production of a number of continuous
leaves of paper which are cross-perforated at preselected intervals
to faclitate transverse folding to produce a pack, is not directly
related to the gluing, fastening and alignment problems above set
forth but is instead, related to the difficulties produced as a
result of diverse customer demands. In this regard, depending upon
the ultimate use to which the prepared sheets will be placed, the
distance between adjacent transverse perforations in the sheets may
vary substantially. For example, if the continuous sheets are to be
used in connection with computerized printers and the like, the
distance between perforation lines may be on the order of 11 inches
with the interconnected sections remaining connected until the
print-out is completed, whereupon the final section of the
print-out is snapped free of the next adjacent, unprinted section
along a perforated fold line.
On the other hand, where the continuous sheets are to be used in
various types of business forms which may often be 3 2/3 or 5 1/2
inches in length, there is a need to produce the perforation lines
at much smaller intervals to allow the individual forms to be
separated from one another. In both instances, even though the
articles themselves may be 3 2/3, 5 1/2, or 11 inches in length, it
is beneficial from a storing and handling standpoint to fold the
sheets at common intervals such as 11 inches so that, in the case
of the shorter forms, tow or more of the forms may appear in each
layer of the pack of sheets produced when the sheets are folded in
opposite directions at 11 inch intervals. For purposes of clarity
throughout the description hereinbelow set forth, in order to
distinguish between the lines along which the sections are folded
from the perforation lines intermediate the fold lines, the
perforations which define the folding points will be referred to as
"perforation fold lines", while those perforations intermediate the
fold lines will be referred to as "perforation tear lines",
although it is to be understood that the sheets may, in fact, be
torn along any of such perforation lines and, in most cases, the
fold lines will have perforations identical in character to one
another.
Moreover, the user often needs sheets which are folded at other
than 11 inch intervals such as, for example, 7, 8 1/2, 12 or 14
inch intervals to satisfy his particular requirements. Each of
these latter intervals may be further subdivided to produce a
multitude of sizes which the individual articles or sections may
assume.
Because of the many diverse lengths of articles which may be
required from time to time, a certain amount of "down-time" is
necessarily involved in order to modify the working components of
the production apparatus to produce a product having the
perforation characteristics desired by one user in lieu of those
characteristics desired by another user. Ideally, such down-time
should be maintained at a minimum since the amount of time that the
production apparatus stands idle directly affects the total amount
of job time for a particular order as well as the overall operating
efficiency of the apparatus.
Accordingly, one important object of the present invention is to
provide a highly flexible system of crossperforating continuous,
superimposed leaves or sheets in order to accommodate widely
diversified user demands in terms of article size and fold lengths,
all without sacrificing high quality and precision associated with
the products fabricated in accordance with the gluing process
incident to the production of the product.
Another important object of the present invention is to provide a
flexible perforating system as above set forth wherein the
perforation lines which serve as fold lines for the continuous
sheets are alternately produced from opposite directions so that
the sheets themselves may be readily folded in opposite directions
at the fold lines to produce a pack formed without "back folding"
on any of the fold lines. Back folds are caused when alternate fold
lines are produced from the same direction and the individual
sections of sheets are folded back over one another to produce the
pack so that every other fold line "goes against the grain" of the
perforations defining such lines.
A further important object of the instant invention is to provide a
cross-perforating system of high flexibility wherein one
perforating head may be used continuously for a normal production
run having a predetermined fold line interval for the sheets
processed by the perforating head, while another perforating head
used for producing intermediate tear line cross-perforations
between the fold line perforations may be maintained in a standby
or idle condition during the normal production run until a modified
run requiring a selected number of such tear lines between the fold
lines is required.
Yet another important object of our invention is to provide a
cross-perforating system as aforesaid wherein the individual
perforating heads of the system may be readily removed and replaced
with new heads which are capable of producing fold lines and tear
lines intermediate the fold lines at spaced intervals which differ
substantially from those possible with the replaced perforating
heads.
Other objects and aims wll be made clear or become apparent as the
following specification progresses, reference being had to the
accompanying drawing, wherein:
FIG. 1 is a schematic, side elevational view of equipment capable
of use in carrying out the method of glue fastening of superimposed
leaves hereinbelow set forth;
FIG. 2 is a schematic top plan view of the equipment illustrated in
FIG. 1;
FIG. 3 is a perspective view of a pack of continuous business forms
or the like, partially unfolded and with one corner pulled back for
illustrating certain details of construction;
FIG. 4 is a fragmentary, top plan view of the forms shown in FIG.
3, the aforementioned corner being broken away for clearness;
FIG. 5 is a transverse cross-sectional view through the forms
illustrated in FIG. 3;
FIG. 6 is a fragmentary, longitudinal cross-sectional view through
the forms showing one type of cross perforator;
FIG. 7 is a cross-sectional view through one of the nozzles
employed in the equipment shown by FIGS. 1 and 2 for depositing a
line of glue onto the sheets as they are advanced through the
collator;
FIG. 8 is a schematic, side elevational view similar to FIG. 1 of
apparatus capable of use in carrying out the method of
cross-perforation of superimposed leaves in accordance with the
concepts of our present invention;
FIG. 9 is a schematic, top plan view of the apparatus illustrated
in FIG. 8;
FIG. 10 is an enlarged, fragmentary, schematic side elevational
view of the perforating apparatus illustrating the two perforating
heads thereof; and
FIG. 11 is a perspective view similar to FIG. 3 of a pack of
continuous business forms or the like illustrating the provision of
intermediate perforation tear lines between pairs of the
perforation fold lines.
DESCRIPTION OF FIGS. 1-7
For convenience, the method hereinafter described in connection
with FIGS. 1-7 will be illustrated in conjunction with the
production of a pack 10 of continuous business forms 12 having
equally spaced transverse lines of perforation 14, and especially
adapted for use in computerized or data-processing printers and
other comparable equipment. It is to be understood, however, that
such terminology does not preclude advantageous use of our method
in connection with the glue fastening of superimposed leaves or
sheets of paper having various other uses, including, therefore,
stationery and other products.
The form chosen for illustration of our production method, broadly
designed by the numeral 12 as aforesaid, includes a top sheet or
leaf of paper 16, a sheet of carbon paper 18 attached to the sheet
16 therebelow, a second sheet of paper 20 beneath the carbon 18, a
second sheet of carbon paper 22 beneath the sheet 20 and attached
thereto, and a third or bottom sheet of paper 24 beneath the carbon
22. It is to be understood, however, that in accordance with the
method about to be described, the form 12 may consist of any number
of additional sheets as at 16, 20 and 24 with a corresponding
number of carbons as at 18 and 22. Moreover, it is not necessary
that the pack 10 include the carbons 18 and 22, or any carbons, as
in the case of self-contained reproducing paper.
Moreover, the product shown in FIGS. 3, 4 and 5 may have rows of
holes or openings 26 and 28 adjacent the longitudinal edges of the
sheets 16, 20 and 24, but since the carbons 18 and 22 do not extend
the full width of the sheets 16, 20, and 24, the holes 26 and 28 do
not pass through the carbon paper.
Furthermore, the product chosen for illustration is provided with a
longitudinal line of perforations 30 which pass through all of the
sheets 16, 18, 22 and 24, presenting a marginal stub 32 which may
be snapped away after processing through the printer, thereby
separating all of the sheets 16, 18, 20, 22 and 24, and permitting
desired distribution of the individual sheets 16, 20 and 24 when
the same are torn apart along the lines of perforation 14.
To this end, therefore, the carbons 18 and 22 are attached to their
corresponding sheets 16 and 20 respectively by longitudinal lines
of glue 34 within the stub portion 32, i.e., outwardly of but
adjacent the line of perforation 30. On the other hand, the sheet
16 is fastened to the sheets 20, and the sheet 20 is fastened to
the sheet 24 by glue lines 36 extending continuously throughout the
length of the stub 32 adjacent the outermost longitudinal edge
thereof with holes or openings 28 located between the glue lines 34
and 36.
In FIGS. 1 and 2 of the drawing, a collator broadly designated by
the numeral 38 supports supply drums 40, 42, 44, 46 and 48 for the
continuous sheets or leaves 16, 18, 20, 22 and 24 which are
advanced horizontally (from right to left viewing FIGS. 1 and 2),
to place such sheets in superimposed relationship, by rotatable
drive rollers 50 which may or may not have radial pins at their
peripheries for receiving the holes 26 and 28 of the sheets 16, 20
and 24.
Collator 38 is equipped with a number of special nozzles 52 for
depositing a line of glue on the sheets during their advancement.
Such nozzles 52 are preferably formed from a nonoxidizing,
malleable or nonmalleable material capable of receiving copies of
required dimensions, as illustrated in FIG. 7 in the drawing. It is
extremely important that the nozzle 52 direct a very fine stream of
glue to the sheets, and we have been particularly successful in
carrying out our method by the selection of an orifice 54 for the
nozzle 52 that has a size in the order of from 0.005 to .0937
inches.
Moreover, in order to cause the glue to rise and string out before
reaching the sheets, thus forming narrower glue lines 36 of minimum
thickness than is made possible by a standard nozzle, we have cut
the head 56 of the nozzle 52 at an angle of approximately
5.degree., the sheets traveling with respect to the head 56 in the
direction of arrow 58 in FIG. 7.
We have found that the so-called hot glues universally used in many
applications within this field are not entirely satisfactory for
many reasons, including the fact that such glues must be reduced
both in temperature and in moisture content before they effectively
bond the sheets together and there is no satisfactory drying and
cooling means for such glues which will permit high speed
production at relatively low manufacturing costs. Moreover, the hot
glues form a jell on reduction of temperature, causing them to grab
onto the fibers of the paper too quickly, thereby aggravating the
problem of maintaining the sheets in proper alignment, i.e., with
their holes 26 and 28 in full and direct register.
We have also determined that the conventional animal and dextrin
glues are not entirely satisfactory because of the fact that solids
are in suspension within the liquid content thereof such that glues
of that type are too slow to set up and dry and not conductive to
obtaining the rather large number of desired results made possible
through use of our present method.
Therefore, the glue to be dispensed from the nozzles 52 is
desirably a cold glue that is easy to handle, requiring no heat to
maintain it in a fluid condition and requiring no equipment for
reduction of the temperature thereof, it being contemplated that
the glue emanating from the nozzles 52 be at room temperature. In
this connection we prefer to use an emulsion having a polyvinyl
base with a water content of approximately 40 percent including the
usual plastercizers, and having the polyvinyl acetate solids
emulsified therein, as distinguished from dextrin and animal
solutions, wherein the solid particles are in ordinary
suspension.
Depending upon the base resin, such glues tend to set rather
quickly, particularly upon application of pressure, and thereupon
are capable of rapid evaporation of their moisture content.
Therefore, as soon as the sheets 20 and 24 come into engagement
with the glue lines 36 thereabove, such glue tends to immmediately
grab onto the fibers of the papers and hold them against slippage
relatively, but, by the same token the selected glue is
characterized by the fact that sufficient relative slippage between
the sheets 16, 20 and 24 is permitted to maintain the holes 26 and
28 aligned and in register while the remaining steps of the process
are carried out.
We also prefer to use pulsed microwave energy to generate internal
heating of the glue in a concentrated area which may be confined to
approximately one-eighth inch wide or less, thereby causing rapid
drying and bonding in the stub construction 32 of continuous as
well as snap-apart business forms and stationery. Such microwave
internal heating in a concentrated area, as distinguished from
induced heating over the entire form area, can be produced through
use of a magnetron 60 in which the flow of electrons is controlled
by an externally applied magnetic field to generate power at
microwave frequencies, such very short electromagnetic waves
normally being between approximately 100 centimeters and one
centimeter in wave length. Such microwaves, in the vicinity of
about 2,400 megacycles, are capable of developing tremendous heat
and energy, combined in a relatively small space conducted to the
exact zone where heat is needed without introduction of undesired
heat into those areas of the sheets where the paper and the carbon
might be adversely affected, which has been a detriment to optimum
results in all previous systems and methods. Accordingly, the wave
guide section 62 of the magnetron generator 60 need not exceed more
than approximately 4 feet in length thereby reducing the drying
time to a minimum and permitting high speed production. Such
internal heating of the glue to evaporate its moisture content
prevents damage to the carbon papers 18 and 22 because their oil
based carrying agent will not dry out, nor will there be any
spoilage of the paper sheets 16, 20, or 24 by burning or
scorching.
It has been found advisable also to use pinned drums, rollers or
the like 64 at the drying section to move the superimposed sheets
simultaneously along the section 62 and maintain them in proper
alignment until such time as the glue is completely dry and full
and effective bonding of the sheets together has been effected. As
above mentioned, the glue which we have selected permits sufficient
slippage of the sheets relatively to cause such proper alignment
during first contact of the paper parts. Yet, because of the fast
setting characteristics of the glue after water has been removed by
microwave created heat, the complete, firm and final fastening of
the sheets one to another is made possible during the very short
period during which the glue lines 36 are subjected to the
generator 60.
From the dryer 60 the sheets are advanced through a perforating
head 64 to produce the transverse lines of perforation 14. It is of
course possible to interpose the head 64 ahead of the dryer 60, but
the step of perforating tends to shift the sheets out of alignment
and we have, therefore, found it to be preferable to have complete
and firm bonding of the sheets prior to subjecting them to the
perforator 64.
In FIG. 6 of the drawings there is illustrated upper and lower
perforating drums 66 and 68 provided with diametrically opposed
perforating blades 70 and 72 respectively and timed in their
rotation such as to alternately perforate the sheets along the
lines 14 from the top and from the bottom. Such alternating
function of the drums 66 and 68 of the head 64 is advantageous from
the standpoint of proper folding in folder section 74 along the
lines 14 to produce the pack 10 as shown in FIG. 3. Alternatively,
the drum 68 could be in the form of an anvil with all of the blades
on the drum 66 such that formation of the lines 14 would be from
the top only, but such arrangement causes a back fold on every
other cross perforation which limits the number of superimposed
sheets to no more than eight and, in turn, is less desirable than
drums of the kind illustrated at 66 and 68 in FIG. 6 of the
drawing.
It is now apparent that with the sheets 16, 20 and 24 fully and
properly bonded together along the glue lines 36, there will be no
separation or tenting at the lines of fold along the perforation
lines 14, eliminating, therefore, the problems of jamming and other
malfunctions which are quite common in the use of a product of this
nature in printing machines and other equipment.
In order to accomplish the desired results as hereinabove initially
outlined, it is also extremely important that the glue lines 36 be
very narrow and of minimal thickness for many reasons. By providing
for only sufficient surface impregnation of the paper fibers such
as to effect good bonding, the stub area 32 will not become unduly
rigid and inflexible along the glue lines 36, not only making it
possible to form the sheets into a compact stack 10, but reducing
problems incident to the feeding of the forms through computerized
printers and the like. Such minimum bulkiness at the glue lines 36
is made possible by applying the glue continuously and uniformly
and by selection of a glue nozzle, as well as a drying process,
which will eliminate zones of separation along the glue lines 36
and eliminate formation of dried glue crystals, lumps and the like
which are incapable of holding the sheets properly bonded
together.
It is to be understood also that the glue line 36 may be produced
along more than one longitudinal edge of the forms 12; in certain
instances it is desirable or necessary to duplicate the glue
applying and drying steps along that edge of the forms 12 having
the openings or holes 26 therein. The gluing method is also fully
adaptable for use in making various types of snap-out forms, as
above indicated. Moreover, it is not necessary to utilize the stub
feature 32 with the line of perforations 30 in the manner and for
the purpose above described.
Concentrated heating along the glue lines 36 is important because
it avoids damage to the carbons 18 and 22. In some instances,
processed carbons are used having the same width as the sheets 16,
20 and 24 with the holes 26 and 28 also passing through the carbon
sheets. However, the marginal edges are kraft paper, not
carbonized; hence, even in such instances the adjacent carbon areas
will not be damaged.
The gluing process also affords a complete and proper method of
fastening the entire set of forms together by the application of
the glue lines to the face and back of paper sheet 20, whereby the
glue lines are applied so as to fasten the paper to the carbon
below, and this carbon in turn is fastened to the sheet below it,
thus accomplishing the manufacture of extremely flexible forms
which will allow the complete set to pass easily around the platen
of a typewriter or a computer printr which utilizes a small round
platen and, therefore, is more prone to jam when a bulky form is
passed over and around the small platen. This is to be done by the
use of processed carbon paper with the holes 26 and 28 also passing
through the carbon sheets, thus allowing the pins on the drums to
function in their capacity of moving the sheets forward while the
gluing and drying functions are being performed. Under special
conditions were a wider stub is permissible, this form of
construction can be effected without the use of the holes 26 and 28
in the carbon, by moving the carbon away from the edge and applying
the glue and microwave heat to the form on the inside areas of the
pin feed device.
Important also is the fact that the gluing process may be
accomplished without the necessity of using slow speed zigzag type
folders with tucker blades, thereby enabling the use of high speed
folding equipment such as, but not limited to, spiral and/or air
jet or vacuum type folders operating at their fullest rated speed
and capacity.
While it is preferred that the adhesive appear in the form of a
continuous, elongated, narrow, thin line, it is also possible to
accomplish spot gluing or interrupted lines. In certain instances
it may be desirable, for example, to omit the glue at the lines of
fold.
DESCRIPTION OF FIGS. 8-11
The apparatus 76 illustrated in FIGS. 8-11 is designed to perform
the same assembling, gluing, and folding operations as the
equipment of FIGS. 1-7, with the additional capability of
cross-perforating the sheets being processed at variable locations
along the sheets. As before, the finished product is a continuous,
multi-leaved web having, for example, individual sections 78 which
may be alternately folded in opposite directions along perforation
fold lines 80 to produce a finished pack 82. In contrast to the web
produced by the equipment of FIGS. 1-7, however, the web produced
by apparatus 76 has any selected number of perforation tear lines
84 located between an adjacent pair of fold lines 80 to subdivide
each section 78 into two or more end-to-end articles 86 which
retain the lines 80 as the fold lines for producing the pack
82.
Apparatus 76 includes a collating and gluing portion 88 for
bringing the various sheets or leaves of the web into superimposed,
aligned relationship with one another in the manner of the
collating mechanism of FIGS. 1 and 2 and for applying a precisely
controlled line of adhesive to the sheets to bond them in the
manner hereinbefore described. The microwave dryer 90 downstream
from the collating and gluing portion 88 receives the web with the
adhesive applied to the sheets thereof and completes the special
drying and curing of the adhesive as set forth above for ultimate
delivery of the web to the folder unit 92 at the left end of the
apparatus 76 viewing FIGS. 8 and 9.
Interposed between the microwave dryer 90 and the folder unit 92 is
a special perforating component 94 having supporting framework
structure broadly denoted by the numeral 96 which carries a pair of
individual perforating heads 98 and 100 which are spaced apart
along the path of travel of the web of sheets. The head 98 is
removably mounted upon frame 96 by mounting bolts 102 and has a
pair of opposed, rotary drums 104 and 106, each capable of carrying
one or more elongated, peripherally disposed perforating blades
108. As shown in FIG. 10, the perforating blades 108 of drums 104
and 106 are angularly offset with respect to one another in
diametrically opposed relationship so that the blades 108 engage
the web moving between drums 104 and 106 at spaced intervals and
from opposite directions to produce the fold lines 80 as earlier
described with regard to FIGS. 1-7.
The perforating head 100 is also removably mounted on frame 96 by a
plurality of bolts 110 and includes a rotary drum 112 similar to
drums 104 and 106. Drum 112 carries a predetermined number of
perforating blades 114 which cooperate with a rotary anvil 116
below drum 112 to produce perforation tear lines 84.
For reasons which will hereinafter appear, whether or not
perforating head 100 is located upstream or downstream from head 98
is not critical to the present invention, although for illustration
purposes head 100 has been shown in an upstream relationship to
head 98. Moreover, in upstream relationship to both heads 98 and
100 is a third perforating head 118 interposed between the
microwave dryer 90 and the collating and gluing portion 88.
Perforating head 118 has at least one drum assembly and opposing
anvil (not shown) as in the case of head 100, but alternatively,
may be provided with a pair of drum assemblies as in the case of
head 98.
In accordance with the principles of our present invention the
heads 100 and 118 may be disabled by disconnecting their drive
connections so that the head 98 may function alone. It is to be
understood that the drums 104 and 106 of head 98 may carry any
number of perforating blades 108 and may be of any selected
diameter in order to produce perforation fold lines 80 at selected
intervals along the web of sheets. By way of example, it may be
desired to fold the web at 11 inch intervals, whereupon the head 98
may have drums 104 and 106 which are 22 inches in circumference
with the blades 108 diametrically opposed to one another so as to
produce fold lines 80 at 11 inch intervals. If it is desired to
produce a web having fold lines 80 at, for example, 7, 81/2, 101/2
or 12 inch intervals, then it is but necessary to release the bolts
102 and replace the head 98 with one having the appropriately sized
drums.
It is contemplated that once a head 98 has been selected which has
the appropriately sized drums 104 and 106, many job orders
requiring perforations only along the points of fold without
intermediate cross-perforations, may be handled on a day-to-day
basis. However, should an order be received which calls for
specially sized business forms, for example, which are smaller in
size than the fold intervals, the head 100 may be placed in
operation to provide the necessary tear lines 84 while retaining
the required fold intervals defined by fold lines 80.
For example, if the fold line interval is 11 inches with the drums
104 and 106 being 22 inches in circumference, a single tear line 84
may be produced at 5 1/2 inches between each pair of fold lines 80
by using a head 100 having a drum 112 which is 22 inches in
circumference and has perforating blades 114 diametrically opposed
to one another and each offset 90.degree. relative to the blades
108 of head 98. Should the required size of each article 86 be less
than 5 1/2 inches while maintaining an 11 inch fold interval, the
drum 112 of head 100 may be provided with such additional blades
114, angularly offset in the appropriate manner, as may be required
to produce the desired number of tear lines 84 between each pair of
fold lines 80.
By virtue of the variable number of blades 114 which may be carried
by drum 112 and the removable mounting feature for each of the
heads 98 and 100, a multitude of spacing combinations may be
obtained for the fold lines 80 and the tear lines 84 so that
virtually all size requirements may be accommodated. Moreover, and
perhaps more importantly, is the fact that such size accommodations
may be made with a minimum of down-time, particularly in those
situations in which only an additional number of tear lines 84 are
required on an existing fold interval. In these situations, it is
but necessary to place the head 100, which has prior to this time
been idle, in operation along with the heretofore operating head
100. Furthermore, even in those situations which require a
substitution of new heads for the heads 90 and 100, the removal and
replacement process may be quickly and easily effected by virtue of
the releasable mounting bolts 102 and 110 for the heads.
The present invention allows the economical interruption of a
production run to insert a priority customer order requiring, for
example, a different size head, i.e., change from a 22 inch head to
a 17 inch head without disturbing the 22 inch head setup, and then
allows return to the 22 inch head after the priority order is
complete without any further time loss. To our knowledge this is
the first time a machine has been designed to accomplish this.
There have been other attempts to solve this rapid changeover
problem, using rotating multi-head systems, or variable gear ratio
systems, none of which has been entirely successful because of the
extreme difficulty of obtaining close enough tolerance, and the
problem that after some months of use the wear on the components
produces a degree of variation that cannot be tolerated. This new
invention accomplishes the desired rapid change-over, maintains the
desired accuracy, eliminates the problem of variation because of
wear, and requires no more maintenance than the older systems that
do not provide the required versatility.
It is to be further pointed out that the folding of the web along
lines 80 in opposite directions may be facilitated by producing the
tear lines 84 from one direction only instead of producing them
from opposite directions as is the case with every other fold line
80. Thus, only one drum 112 is provided with perforating blades 114
while the anvil 116 is devoid of such blades and serves only to
cooperate with blades 114 in producing the tear lines 84.
Apparently, the practice of producing the tear lines 84 from only
one direction means that in many instances, the web would have to
fold back against the grain of the tear line 84 in order to fold
into the pack 82 and such against the grain folding offers more
resistance than the reverse folding at line 80.
In certain situations where the heads 98 and 100 are not
appropriate for use because of the special fold intervals required,
the head 118 may be removed from its disabled condition and placed
in use in lieu of heads 98 and 100, thus affording an additional
cross-perforating station for added flexibility in production.
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