Information
-
Patent Grant
-
6302392
-
Patent Number
6,302,392
-
Date Filed
Tuesday, December 29, 199825 years ago
-
Date Issued
Tuesday, October 16, 200122 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Ellis; Christopher P.
- Ridley; Richard
Agents
- Michael Best & Friedrich LLP
-
CPC
-
US Classifications
Field of Search
US
- 271 279
- 271 303
- 271 302
- 271 305
- 271 272
- 271 283
- 271 186
-
International Classifications
-
Abstract
Provided is a sheet diverter for directing signatures moving in serial fashion along a diverter path to one of a plurality of collation paths. The sheet diverter includes a pair of diverter rolls for directing a signature to one of the plurality of collation paths and a diverter wedge for deflecting the signature to a selected one thereof. The diverter wedge is positioned between the diverter rolls so as to reach high into the diverter path thereby providing increased support to the signature as it travels from between the diverter rolls to the diverter wedge. The diverter rolls are permitted to intermesh with the diverter wedge so as to allow the diverter wedge to be so positioned.
Description
FIELD OF THE INVENTION
The present invention relates, generally, to sheet diverters for directing sheets moving in serial fashion along a path to one of a plurality of collation paths and, more particularly, to a high speed sheet diverter of the foregoing kind for collation of printed signatures to be used in the binding of a publication such as a magazine or a newspaper. The present invention further relates to an improved diverter assembly for collating sheets, such as signatures, from a high speed printing press. Specifically, the present invention provides a sheet diverter with diverter rolls and a diverter wedge positioned therebetween, the function of which is to allow for faster operating machine speeds with fewer jams and, at the same time, to improve the collation process such that the quality of signatures is improved as the signatures move along one of a plurality of collation paths.
BACKGROUND OF THE INVENTION
Sheet diverters may range from the collating apparatus associated with an office copier, to sheet or web handling devices employed in the manufacture of paperboard articles, to sheet diverters specifically adapted to collate signatures to be used in binding or otherwise assembling books, magazines or newspapers. Each of these environments presents a somewhat different challenge in designing an efficient diverter or collator, but the same objective applies to the entire class of apparatus, namely, accurately routing selected flexible webs or ribbon sections along a desired collating path to achieve a desired order.
In the printing industry, an image is repeatedly printed on a continuous web or substrate such as paper. The ink is dried by running the web through curing ovens. In a typical printing process, the continuous web is subsequently slit (in the longitudinal direction which is the direction of web movement) to produce a plurality of continuous ribbons. The ribbons are aligned one on top of the other, folded longitudinally, and then cut laterally to produce a plurality of multi-paged, approximately page length web segments, termed signatures. A signature can also be one printed sheet of paper that has or has not been folded. It is often desirable to transport successive signatures in different directions or paths. In general, a sheet diverter operates to route a signature along a desired one of a plurality of paths.
A sheet diverter in a folder towards the end of a printing press line must be operable at the high speeds of the press line, typically in excess of 2,000-2,500 feet per minute (fpm). It is desirable to run both the press, folder and other equipment in the printing press line at the highest speed possible to produce as many printed products as possible in a given amount of time. However, the physical qualities of printed paper or similar flexible substrates moving at a high rate of speed can result in undesirable whipping, dog-earring, tearing, smearing of the ink, or bunching of the substrate. Additionally, impact between the leading edge of a signature and a diverter wedge may result in the leading edge of the signature being dented or dog-eared or damaged in other ways. Moreover, the trailing edge of a signature may slap against the top edge of a diverter wedge, resulting in tears, dog-ears or other damage to the trailing edge. Damaged signatures may be of reduced or unacceptable quality and may also lead to jams in the folder, resulting in downtime, repair expense and much wasted paper.
Another problem which occurs when operating a press and a folder at high speeds is that signatures may be routed to an undesired one of a plurality of collation paths. As the leading edge of a signature approaches the apex of a diverter wedge, depending on the stiffness of the signature and due to the relationship between the diverter and the diverter wedge, the signature may be delivered to the wrong side of the diverter wedge thereby sending the signature down the wrong collation path. This leads to jams in the folder causing delays and expense.
Yet another problem when operating a printing line at high speeds concerns ink offset in the diverter. As a signature impacts a diverter wedge, non-dried ink may transfer to the surface of the diverter wedge. As successive signatures contact the diverter wedge, the ink transferred to the diverter wedge may undesirably pass to the other signatures. The greater the impact of the signatures against the diverter wedge, the greater the likelihood of ink offset.
Many of the foregoing defects become more prevalent above certain speeds of the printing press and folder. For example, such defects may occur when the press is run at speeds greater than 2,500 fpm, but may not occur when the press is run at a slower speed, for example, 2,200 fpm. As printing press speed capabilities have increased, it has become increasingly important to provide a system which allows for individual signatures to be directed down any one of a plurality of selected collation paths without damaging the leading or trailing edge of each signature or causing jams.
U.S. Pat. No. 4,373,713 discloses a diverter mechanism placed in a path of a stream of cut sheets comprising a pair of rotary diverters with raised cam surfaces used to divert and guide the sheets. A tapered guide has a pair of diverging guide surfaces and has its upstream tapered end interposed between the rotary diverters with raised cam surfaces and diverging tapes.
A sheet diverter for signature collation and a method thereof is described in U.S. Pat. No. 4,729,282, assigned to Quad/Tech, Inc., of Pewaukee, Wis., and is hereby incorporated by reference. The '282 patent discloses a sheet diverter including an oscillating diverter guide member that directs successive signatures to opposite sides of a diverter wedge. As set forth in the '282 patent, the diverter design disclosed in the '713 patent is not viewed as workable in light of the high speeds sought to be attained nor is it seen to be particularly reliable in reducing jamming tendencies which are expected to arise in these settings.
SUMMARY OF THE INVENTION
Diverting devices are used in the printing industry to divert individual signatures along alternating paths in the folder part of a printing press line. Because the diverting operation has a slow processing velocity in relation to the rest of the line, the industry seeks to speed up this operation while reducing damage to the signatures and avoiding jams.
There is a need for a sheet diverter that is capable of operating at high speeds, e.g., in excess of 2,500-3,000 fpm and above, and yet also capable of providing a signature that is acceptable in quality. What is also needed is a sheet diverter for use in the printing industry such that the sheet diverter improves the collation process of printed signatures to prevent or minimize damage to the signatures as the signatures move along one of a plurality of collation paths to increase the quality of each signature, allow for greater operational speeds and reduce downtime and repair expenses associated with jams in a folder. What is further needed is a sheet diverter for use in a high speed printing press line which is designed to prevent or minimize the transfer of non-dried ink to a diverter wedge of the sheet diverter thereby enhancing the overall quality of the printed signatures.
In one embodiment of the present invention, a diverter assembly for diverting signatures from a diverter path to a desired one of a plurality of collation paths is provided. A pair of spaced apart, rotating diverter rolls have respective travel paths which define a common swipe path for the diverter rolls. A diverter wedge which separates the plurality of collation paths is positioned between the pair of diverter rolls such that a portion of the diverter wedge extends into the common swipe path. Positioning the diverter wedge in the common swipe path of the diverter rolls allows for increased control over signatures traveling through a folder as compared to prior known apparatus and methods thereby allowing for greater operational speeds, decreasing signature damage, less ink offset to the diverter wedge and reducing jamming tendencies in a folder.
In another embodiment of the present invention, a sheet diverter for diverting signatures delivered from a printing press to a selected one of a plurality of collation paths is provided. The sheet diverter includes an oscillating diverter device for directing a leading edge of a signature to one of the plurality of collation paths. The sheet diverter also includes a diverter which separates the plurality of collation paths for deflecting a signature to a selected one thereof. The oscillating diverter device and the diverter are capable of intermeshing at appropriate times so as to increase control over signatures traveling through a folder as compared to prior known apparatus and methods thereby also allowing for faster operational speeds, decreasing signature damage, less ink offset and reducing jamming tendencies in a folder.
In yet another embodiment of the present invention, a method for collating signatures delivered from a high speed printing press is provided. A signature is delivered to a pair of oscillating diverter rolls which generally translate over a reciprocable path which is generally normal to the path of the signatures. The translation of the diverter rolls with respect to a diverter wedge positioned therebetween is such that damage to the signatures is substantially minimized or prevented as the signatures travel to and past the diverter wedge thereby allowing for increased operating speeds with fewer jams. The translation of the diverter rolls is properly timed or adjusted with respect to the approach or position of the signatures in relation to the diverter rolls.
Accordingly, it is a feature of the present invention to provide an apparatus and a method thereof that minimizes the potential for damage to signatures as they travel down one of a plurality of collation paths, while also allowing for increased operating speeds.
Another feature of the present invention is to provide a sheet diverter in a printing press operation that provides for improved collation of signatures therethrough while eliminating the need for expensive, complicated equipment as is currently used in the industry. Thus, a feature of the invention is to provide a simple, inexpensive device to improve the collation process in a sheet diverter of a printing press and folding operation.
Yet another feature of the present invention is to provide a diverter in a printing press capable of operating at excessive speed, e.g., in excess of 2,500-3,000 fpm and above, and yet also capable of producing signatures of acceptable quality standards, while at the same time reducing jams which would normally occur in prior known devices if such devices were operated at the contemplated rates of speed discussed herein, all of which thereby minimizes machine downtime and repair expenses, and increases product output over a specified period of time.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a partial schematic diagram of a pinless folder incorporating a sheet diverter in which the present invention may be employed.
FIG. 2
is a partial perspective view of portions of a sheet diverter according to the present invention.
FIGS. 3-5
are cross section side views of a sheet diverter according to the present invention showing the advancement of a signature past a diverter as the signature travels to a selected one of a plurality of collation paths.
FIG. 6
is an enlarged view of a portion of the sheet diverter shown in
FIGS. 3-5
.
FIG. 7
is a front view of a sheet diverter of the present invention with one diverter roll removed showing the relationship between certain components of the sheet diverter.
FIG. 8
is a cross section side view of a diverter wedge of a sheet diverter according to another embodiment of the present invention.
FIG. 9
is an illustrative view of a sheet diverter wedge of a sheet diverter according to yet another embodiment of the present invention.
FIG. 10
is an illustrative view of the sheet diverter of
FIG. 1
showing in greater detail another aspect of the present invention.
Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The use of “consisting of” and variations thereof herein is meant to encompass only the items listed thereafter.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Illustrated in
FIG. 1
of the drawings is a partial schematic diagram of a pinless folder
10
which is a portion of a high speed printing press (not shown). A typical folder includes a forming section, a driving section, a cutting section, a diverting section and a collating section. The invention described herein is primarily directed to a diverter section. A description of a typical forming section, driving section, cutting section, and collating section is found in U.S. Pat. No. 4,729,282, which has been incorporated herein by reference. Shown in
FIG. 1
, among other things, is a diverter section
12
in which the present invention may be employed.
Upstream of the diverter section
12
shown in
FIG. 1
, a forming section, such as that described in the '282 patent, may be provided which may include a generally triangularly shaped former board which receives a web of material (or several longitudinally slit sections of the web termed “ribbons”, wherein the ribbons are typically aligned one on top of the other) and folds the same. The fold is in a direction parallel to the direction of web travel. The folded web is then fed downwardly through a drive section and a cutting section in like manner as that also described in the '282 patent.
Once the web has been transformed into a plurality of individual signatures, successive signatures enter the diverter section
12
along a diverter path
14
. The signatures are led serially via opposed tapes or belts
16
and
18
to a sheet diverter
20
, which includes an oscillating diverter device
22
and a diverter
24
. The diverter assembly
20
deflects a signature to a selected one of a plurality of collation paths
26
or
28
. The signature then enters a collating section
30
and is transported along one of the collation paths to a destination such as a fan delivery device
32
and subsequently to a conveyor (not shown), such as a shingling conveyor, as is known in the art.
The diverter device
22
of the sheet diverter
20
includes a pair of oscillating counter-rotating diverter idler rolls
34
and
36
eccentrically located on driven counter-rotating shafts. The diverter device
22
operates to direct the lateral disposition of the leading edge of a signature relative to the diverter
24
which separates the two collation paths
26
and
28
. The diverter device
22
generally reciprocates in a diverter plane which has a component generally perpendicular to the diverter path
14
.
Signatures are routed through the diverter path
14
and to a selected one of the collation paths
26
or
28
under the control of a signature controller means including a primary signature controller
38
and secondary signature controllers
40
and
42
. Preferably, the distance through the sheet diverter
20
between the primary signature controller
38
and respective secondary signature controllers
40
and
42
is less than the length of the signature to be diverted. In this way, the selected secondary signature controller
40
or
42
assumes control of the leading edge of a signature before the primary signature controller
38
releases control of the trailing edge of the same signature. As used herein, the leading edge or end and trailing edge or end refer to the first or last inch or so of a signature length, but, may actually be as much as the first or last three inches or so of a signature length.
The primary and secondary signature controllers
38
,
40
and
42
comprise opposed (face-to-face) belts or tapes
16
and
18
disposed over rollers in endless belt configurations. The primary signature controller
38
includes the first diverter belt
16
and the second diverter belt
18
which circulate in separate continuous loops in the directions shown by the arrows in FIG.
1
and are joined at a nip between a set of idler rollers
44
near the outfeed of a cutting section (not shown), as such is described in the '282 patent. Drive rollers
46
and
48
drive the diverter belts
16
and
18
respectively about, among other certain components in the separate continuous loops, idler rollers
44
, a plurality of idler rollers
50
, signature slow down mechanisms
52
, idler rollers
54
and
56
, and idler rollers
58
and
60
. The diverter belts
16
and
18
are also driven around idler guide rollers
64
. Both diverter belts
16
and
18
are driven by respective drive rollers
46
and
48
at the same speed, which typically is from 8% to 15% faster than the speed of the printing press. The faster speed of the belts
16
and
18
causes a gap to occur between successive signatures as the signatures move serially and in tandem down path
14
between the diverter belts
16
and
18
. Preferably, for a signature having a length of about 10.875 inches, the gap between successive signatures is approximately between about 1 to 2 inches. Signatures travel generally vertically downward past the diverter
24
along collation paths
26
and
28
so that the signatures are bent as little as possible to avoid damage due to wrinkles at the backbone of the signature and to reduce tail whip of the signatures.
Located downstream of idler rolls
44
is a soft nip
66
defined by an idler roller
68
and an abaxially disposed idler roller
70
. The rollers
68
and
70
cause pressure between diverter belts
16
and
18
as these belts follow the diverter path
14
through the soft nip
66
. The soft nip
66
compressively captures and positively drives a signature that passes therethrough.
The primary signature controller
38
includes an idler guide roll
72
which, with the aid of diverter belts
16
and
18
, helps direct a signature to the oscillating diverter device
22
. A soft nip, similar to soft nip
66
, is defined between idler roll
70
and the abaxially disposed roller
72
.
The secondary signature controllers
40
and
42
include a first collator belt
74
and a second collator belt
76
, respectively, which both circulate in separate continuous loops in the directions shown by the arrows in FIG.
1
. The opposed collator belts
74
and
76
share common paths with the diverter belts
16
and
18
along the collation paths
26
and
28
, beginning downstream of the diverter
24
. In particular, collator belt
74
is transported around idler rollers
64
and
78
, roll
80
of the respective signature slow down mechanism
52
, idler roller
82
, drive roll
84
and idler roll
86
. Collator belt
76
is transported around idler roller
64
, snubber roller
88
of the respective signature slow down mechanism
52
, idler rollers
90
,
92
,
94
, drive roll
96
and idler roll
98
. Idler rollers
100
and
102
also define the paths of the collator belts
74
and
76
. Idler rolls
82
and
94
are belt take-up rolls and are operable to adjust the tension in each belt loop. The tension of diverter belts
16
and
18
can also be adjusted with belt take-up rollers A and B, which are connected via a pivotable lever arm to an air actuator (not shown) that applies adjustable pressure. Since the tension in all four belts can be adjusted, adjustable pressure between opposed belts results to positively hold and transport signatures at tape speeds. Belts
16
and
18
are driven at the same speed as are belts
74
and
76
through the use of timing belts and timing pulleys (not shown).
The secondary signature controller
40
includes a soft nip
104
defined by idler roller
58
operating with the abaxially disposed idler roller
86
, the diverter belt
16
, and the collator belt
74
. Similarly, the secondary signature controller
42
includes a soft nip
106
defined by idler roller
60
operating with the abaxially disposed idler roller
98
, the diverter belt
18
, and the collator belt
76
.
Shown in
FIG. 2
are parts of a sheet diverter according to one embodiment of the present invention. Shown are the diverter device
22
and diverter
24
. The diverter rolls
34
and
36
of the diverter device
22
include outwardly extending, spaced apart, preferably crowned, steps
118
, the function and purpose of which will be explained below. The diverter or diverter wedge
110
mounts to fixture
120
which is appropriately placed stationary in a folder so as to properly locate and firmly support diverter wedge
110
with respect to diverter rolls
34
and
36
. The diverter wedge
110
includes diversion surfaces
114
and
116
diverging from a top vertex
112
to a base
122
which is opposite the top vertex
112
. A diverter nip plane
107
is generally parallel with the diverter nip path
14
(
FIG. 1
) and extends through the top vertex
112
to the middle of the base
122
(see FIG.
9
). With reference to
FIG. 9
, one embodiment of a diverter wedge is shown. Various points A-D are identified on the diversion surfaces
114
and
116
of the diverter wedge
110
. From points A to B, the diversion surfaces
114
and
116
preferably diverge from the top vertex edge
112
at approximately fifteen degrees with respect to the diverter nip plane
107
defining steeply sloped straight surfaces. From points B to C, the diversion surfaces
114
and
116
include generally curved surfaces, preferably having about a three-inch radius. From points C to D, the diversion surfaces
114
and
116
define generally straight surfaces which lead into the respective collating sections and directly into respective soft nips
104
and
106
. The top vertex
112
of the diverter wedge
110
preferably includes a generally rounded surface. The top vertex
112
further includes spaced apart grooves
124
(FIG.
2
). As shown in
FIG. 2
, grooves
124
mesh with adequate clearance with steps
118
of rolls
34
and
36
, the function and purpose of which will be explained below.
An alternative embodiment of a diverter wedge is shown in FIG.
8
. Diverter wedge
111
is similar to diverter wedge
110
except that diversion surfaces
113
include respective air discharge ports
115
which are connectable to a source of pressurized air
117
. The air pressure can be adjusted with external air pressure regulators or needle valves, known to those skilled in the art. Ports
115
are preferably evenly spaced holes extending through the diversion surfaces
113
in the diverter wedge
111
. The air directed through the diversion surfaces
113
assists in sending the signatures down the collation paths by ensuring that the signatures do not stick to and are not appreciably slowed down by the diversion surfaces of the wedge by reducing friction between the diversion surfaces
113
and the signatures.
FIGS. 3-5
show the advancement of a signature past a diverter as the signature travels to a selected one of a plurality of collation paths. The gap of the nip
108
located between the belts
16
and
18
and respective diverter rolls
34
and
36
is preferably dimensioned to be oversized as compared to signature thickness to avoid exerting virtually any compressive force on a signature traveling through the sheet diverter
20
in the sense that a signature can be drawn through the nip
108
without rotation of the rolls
34
and
36
. In operation, at least a first and second diverter belt
16
and
18
carry individual signatures toward the sheet diverter
20
(FIG.
1
). As the diverter rolls
34
and
36
oscillate and translate, as a result of being eccentrically located about driven counter-rotating shafts, the diverter nip
108
moves from one side to the other side of the diverter wedge
110
. A first signature is guided along one diversion surface
114
of the wedge
110
. As the signature moves through the nip
108
, the diverter rolls
34
and
36
continue to oscillate and translate so that nip
108
moves to the other side of the wedge
110
. In this manner, a successive signature is diverted to the other side of the wedge
110
along the diversion surface
116
.
The diverter rolls
34
and
36
include roll centers
126
and
128
. The diverter rolls
34
and
36
rotate about their respective centers and are caused to do so by virtue of being in contact with respective belts
16
and
18
. The diverter rolls
34
and
36
are also journalled for rotation about respective axes
130
and
132
lying in a diverter plane
134
which has a component generally normal to the diverter path
14
of the signatures. Axes
130
and
132
extend lengthwise through the respective rolls
34
and
36
. Preferably, the diverter rolls
34
and
36
are eccentrically located upon respective driven shafts
131
and
133
wherein the axes
130
and
132
lying in the diverter plane
134
extend through respective centers of the shafts. More preferably, each of the eccentrically located diverter rolls
34
and
36
is designed to be approximately one-quarter inch off the axis of the respective shafts, to yield a full eccentric throw of about one-half inch.
It should be noted that in a printing press operation such as that described in reference to
FIG. 1
, two or more collating sections having a plurality of collating paths may be provided. As shown in
FIGS. 2-5
, diverter rolls
34
and
36
cooperate with collation paths
26
and
28
. Although not shown in
FIG. 2
, a second sheet diverter, comprising a mirror image of sheet diverter
20
, may be provided adjacent to sheet diverter
20
. In such an arrangement, more than two collation paths are used to assemble magazines or the like.
Referring again to
FIGS. 3-5
, it can be appreciated that as the diverter rolls
34
and
36
rotate about their own axis
126
or
128
, the roll centers
126
and
128
are caused to orbit about the respective shaft centers
130
and
132
. The orbital motion of the diverter rolls
34
and
36
defines travel paths of the outside diameters of steps
118
for each of the diverter rolls as identified by dotted lines
136
and
138
. As shown, travel paths
136
and
138
partially overlap to define a common swipe path
140
, best seen in
FIG. 6
, the significance of which will be explained below. The diverter wedge
110
, separates the collation paths
26
and
28
and is interposed between the diverter rolls
34
and
36
such that a portion of the diverter wedge
110
extends into the common swipe path
140
(see also FIG.
6
).
The sheet diverter
20
of the present invention routes a signature
142
to an appropriate one of the collation paths
26
or
28
by placement of the leading edge
144
of that signature into appropriate proximate contact with the diverter
24
. In the illustrative embodiment, the diverter wedge
110
is orientated toward the diverter nip
108
and the diversion surfaces
114
and
116
taper downwardly from the apex
112
toward the collation paths
26
and
28
. The belts
16
and
18
are preferably a part of a separate group of segmented belts. With reference to
FIG. 7
in conjunction with what is shown in
FIG. 2
, it can be observed that the belts
16
and
18
are in operative engagement with respective rolls
34
and
36
. Preferably, for every step
118
of rolls
34
and
36
, a separate belt is in operative engagement with that step. The steps
118
are generally crowned to assist in tracking of the belts as they traverse over the steps. The belts
16
and
18
diverge from a point intermediate the diverter rolls
34
and
36
and the diverter wedge
110
along distinct collation paths. The belts
16
and
18
confine a signature
142
therebetween for transport to the diverter wedge
110
such that the signature does not come into contact with either of the diverter rolls
34
or
36
.
With continued reference to
FIGS. 3-5
, signature passageways
148
and
150
are formed between respective diversion surfaces
114
and
116
of the diverter wedge
110
and the respective diverter belts
16
and
18
. As the diverter device
22
reciprocates in the diverter plane
134
, the leading edge
144
of the signature
142
is caused to enter one or the other of the signature passageways
148
or
150
. The diverter belts, diverter rolls and diverter wedge are cooperatively arranged so as not to substantially hinder or pinch a signature as the signature travels down a diverter path, past a diverter to a selected one of a plurality of collation paths.
FIG. 3
shows the leading edge
144
of a signature
142
approaching the top vertex
112
of wedge
110
. As shown, diverter rolls
34
and
36
are positioned along their respective travel paths
136
and
138
so as to direct the leading edge
144
of the signature to one side of the diverter wedge
110
. The timing of the translation of the diverter rolls
34
and
36
is such that the leading edge
144
of the signature
142
will not contact the apex
112
of the diverter
110
which, if it did occur, may damage the leading edge of the signature and could cause a jam in the diverter.
As is apparent in
FIG. 3
, passageway
148
is open and passageway
150
is practically closed. Passageways
148
and
150
tend to open and close as the diverter rolls
34
and
36
reciprocate in the diverter plane
134
. In prior designs, at excessive speeds, because of the relationship between the diverter rolls and the diverter wedge, a signature could be directed down a wrong collation path as a result of passageways on either side of a diverter wedge not being sufficiently closed. As shown in
FIG. 3
, because the diverter wedge reaches into the common swipe path
140
of the diverter rolls
34
and
36
, and because the rolls
34
and
36
translate in a reciprocable path, the passageway
150
is sufficiently closed to prevent the signature
142
from being directed down the wrong collation path, in this case, collation path
28
.
FIG. 4
shows the leading edge
144
of signature
142
as the signature is first guided into initial contact with the diverter wedge
110
. The top vertex
112
and diversion surfaces
114
and
116
of the diverter
24
are designed as set forth above to ease the passage of the signatures along the collation paths. The vertex
112
is preferably rounded to assist in reducing damage to the leading edge or trailing edge of a signature if such should contact the vertex
112
. The upstream portion of the diversion surfaces
114
and
116
are steeply sloped and liberally curved (
FIG. 9
) to reduce the impact force acting on the leading edge
144
of the signature
142
as it strikes against the diverter wedge
110
and to reduce the rubbing pressure on the side of the signature which travels against the diverter wedge so as to prevent or reduce ink offset. The signature
142
is continually advanced along collation path
26
as rolls
34
and
36
rotate and translate. As can be observed in
FIG. 4
, with reference to
FIG. 6
, steps
118
of roll
36
extend beneath diversion surface
116
of wedge
110
during part of the full rotation such that diverter roll
36
meshes with diverter wedge
110
. The steps
118
mesh with grooves
124
of wedge
110
so as not to cause damage from a collision to the diverter roll
36
and diverter wedge
110
. The meshing action between the diverter roll
36
and diverter wedge
110
allows the diverter wedge
110
to extend into the common swipe path
140
of the diverter rolls
34
and
36
. As noted, control over the signature is increased by placing the diverter wedge
110
in the common swipe path
140
of the diverter rolls
34
and
36
.
FIG. 5
shows the trailing edge
146
of the signature
142
as it approaches the apex
112
of diverter wedge
110
. As the diverter rolls
34
and
36
translate along plane
134
, passageway
148
is closing and passageway
150
is opening. The translation of the rolls
34
and
36
is such that the trailing edge
146
of the signature will not be slapped violently against the vertex
112
which would cause tailwhip. This is prevented because the diverter wedge
110
reaches into the common swipe path
140
. The signature
142
is more fully supported as the belts
16
and
18
diverge from the rolls
34
and
36
. In prior sheet diverters, the diverter wedge may be located substantially distant from the diversion point of the belts. Thus, in such prior designs, a significant portion, including the trailing edge, of a signature may be whipped against and across the top vertex of the diverter wedge thereby damaging the trailing edge as set forth above.
Timing the translation of the diverter rolls to the arrival time of the signatures as the signatures are collated from a high speed printing press is one aspect of the present invention. The timing of the translation, which may be manual, semi-automatic or automatic, should be controlled such that when a leading edge of a signature is adjacent to an uppermost portion of a diverter, the diverter rolls direct the leading edge of the signature to one side of the diverter so that the signature leading edge does not contact the top vertex. Moreover, timing the translation of the diverter rolls should be such that the trailing edge of the signature will not whip against the top portion of the diverter as the signature continually travels along the selected collation path.
With reference to
FIG. 4
, a preferred embodiment of the invention will be described. The timing of the translation of diverter rolls
34
and
36
is preferably based on the point in time when the leading edge
144
of the signature
142
first contacts a diversion surface of the diverter wedge
110
. As previously explained, roll centers
126
and
128
are caused to orbit about respective axes
130
and
132
. Position “X” is defined as the angular location of the centers
126
and
128
of diverter rolls
34
and
36
with respect to axes
130
and
132
and plane
134
when the signature first contacts the wedge
110
. In position “X”, it can be observed that roll center
126
is located to the left and below axis
130
and roll center
128
is located to the left and above axis
132
. Diverter roll
34
is located about its travel path
136
in the position shown such that roll center
126
falls on a plane
152
traveling through roll center
126
and axis
130
, the plane
152
being set at a preferred angle of between about 25-45 degrees with respect to plane
134
. Diverter roll
36
is located about its travel path
138
in the position shown such that roll center
128
falls on a plane
154
traveling through roll center
128
and axis
132
, the plane being set at a preferred angle of between about 25-45 degrees with respect to plane
134
. Preferably, the numerical angle value for locating roll
34
with respect to plane
152
and plane
134
is equal to the numerical angle value for locating roll
36
with respect to plane
154
and plane
134
.
Timing the translation and positioning of rolls
34
and
36
as set forth with respect to
FIG. 4
ensures that as a leading edge of a signature approaches apex
112
(FIG.
3
), the leading edge will not sufficiently contact or sufficiently misses the vertex
112
and the signature
142
will not be directed down the wrong collation path
28
. As shown in
FIG. 3
, rolls
34
and
36
have not yet reached position “X” as identified in FIG.
4
. However, based on the timing of the translation of the rolls in order to reach position “X”, the position of the rolls
34
and
36
is timed such that passageway
150
is sufficiently closed and passageway
148
is sufficiently opened so that rolls
34
and
36
properly direct the leading edge
144
of signature
142
to collation path
26
. In addition, proper timing and positioning of the rolls
34
and
36
will ensure that as a trailing edge of a signature approaches apex
112
(FIG.
5
), the trailing edge will not be violently whipped or slapped against or across the apex
112
. As shown in
FIG. 5
, rolls
34
and
36
have translated beyond position “X” as described in FIG.
4
. The translation of the rolls
34
and
36
is timed such that passageway
148
is closing and passageway
150
is opening so that signature
142
is properly directed down collation path
26
and a succeeding signature will be fed down collation path
28
.
It should be noted that for every 180 degrees the drive shafts rotate, one signature travels past the rolls. Thus, with reference to
FIGS. 3-5
, and particularly the just described preferred embodiment, when a succeeding signature is directed to collation path
28
and the signature contacts a surface
116
of a wedge
110
, the location of rolls
34
and
36
will be reversed with respect to the description related to FIG.
4
.
The operation of the present invention may be further explained as follows. As described, when the diverter rolls
34
and
36
translate over a path in the diverter plane
134
in order to direct a signature
142
to a wedge
110
, passageways
148
and
150
tend to open and close. As illustrated in
FIG. 4
, when the signature
142
contacts the wedge
110
, grooves
124
in wedge
110
mesh with sufficient clearance with steps
118
of roll
36
. It should be noted that although the steps
118
, and thereby belts
18
, extend beneath diversion surface
116
, the belts
18
preferably do not contact any part of wedge
110
because such contact may cause the belts to adversely wear. As is apparent with reference to
FIG. 5
, as a succeeding signature is directed to collation path
28
, grooves
124
in wedge
110
will appropriately mesh with sufficient clearance with steps
118
of roll
34
. In this way, the grooves
124
intermittently mesh with steps
118
of rolls
34
and
36
. It should be noted that the timing of the translation and thereby the meshing action of the rolls and wedge is such that the signatures are not hindered or pinched as they travel from the diverter path to the collation paths. As should be evident, if a roll, such as roll
34
, meshes with grooves
124
in the wedge
110
before a signature has traveled past the apex
112
on its way down the collation path
26
, the signature would be pinched between the belts
16
and wedge
110
thereby causing damage to the signature and possibly jamming the machine.
FIG. 10
is an illustrative view of the sheet diverter of
FIG. 1
showing in greater detail another aspect of the present invention. As a signature
142
is traveling past a diverter wedge
110
in a diverter section, it is desirable to prevent the signature
142
from being bent in more than one direction so as to reduce tail whip of the trailing edge
146
of the signature
142
as it travels past the vertex
112
of the diverter wedge
110
. As such, from the point the diverter belts
16
and
18
generally release from respective diverter rolls
34
and
36
to the point the diverter belts
16
and
18
generally engage respective rolls
54
and
56
, the diverter belts
16
and
18
travel in a substantially straight line. The distance between these two points is approximately equal to about the length of one signature. In this way, as a signature
142
travels down one of the collation paths
26
or
28
, the leading edge
144
of a signature
142
will not be directed in another direction until the trailing edge
146
of the signature
142
has traveled past the apex
112
of the diverter
24
. Thus, reducing the likelihood that the trailing edge
146
will be violently whipped against or across the apex
112
of the diverter
24
. In order to achieve the foregoing features, idler rollers
58
and
60
are adjustable generally perpendicular to the respective belt or collator paths
26
or
28
and idler rollers
54
and
56
are adjustable generally parallel to the respective belt or collator paths
26
or
28
.
It is readily apparent from the foregoing detailed description that the sheet diverter of the present invention overcomes the problems of the prior art. The sheet diverter of the present invention may function efficiently in conjunction with a high speed printing press at sheet speeds in excess of 2,500-3,000 fpm or more. Sheets are efficiently diverted into appropriate collation paths at these high speeds with reduced damage to the sheets and with reduced jamming tendencies. Anticipating the occurrences of such jams, which although reduced in tendency could never be made non-existent, the diverter rolls may be designed to pivot away from each other through the use of air cylinders or the like in order to open up a region near the collation paths and diverter so jammed product can be removed. Thus, even in the event of jams, the downtime associated with clearing the apparatus is greatly reduced.
The foregoing description of the present invention has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit the invention in the form disclosed herein. Consequently, variations and modifications commensurate with the above teachings in skill or knowledge of the relevant art, are within the scope of the present invention. The embodiments described herein are further intended to explain the best modes known for practicing the invention and to enable others skilled in the art to utilize the invention as such, or other embodiments and with various modifications required by the particular applications or uses of the present invention. It is intended that the appended claims are to be construed to include alternative embodiments to the extent permitted by the prior art.
Various features of the invention are set forth in the following claims.
Claims
- 1. A diverter assembly for diverting signatures from a single feed path to a plurality of collation paths, said diverter assembly comprising:a pair of diverter rolls adapted to receive signatures therebetween, wherein the diverter rolls reciprocate in a direction that is at least partially normal to the feed path such that the feed path translates between each of the collation paths; a diverter wedge separating the plurality of collation paths, wherein the diverter wedge is interposed between said diverter rolls such that a portion of said diverter wedge extends into the translating feed path between said diverter rolls; and wherein the diverter rolls include outwardly extending spaced apart raised steps and the diverter wedge includes spaced apart grooves in the top vertex edge such that the grooves in the diverter wedge periodically intermesh with the steps on each of the diverter rolls as the diverter rolls reciprocate.
- 2. A diverter assembly according to claim 1, wherein the diverter rolls are counter-rotating.
- 3. A diverter assembly according to claim 2, wherein each of the diverter rolls includes a longitudinal axis that is substantially parallel to the feed path and the longitudinal axis of the other diverter roller.
- 4. A diverter assembly according to claim 3, wherein each of the diverter rolls rotate around a roll center that is substantially parallel to the feed path and is offset from the longitudinal axis of the respective diverter roll such that each of the diverter rolls rotate eccentrically which translates the feed path back and forth between the collation paths.
- 5. A diverter assembly according to claim 1, wherein said diverter wedge includes curved surfaces that diverge from a top vertex edge to a base.
- 6. A diverter assembly according to claim 5, wherein the top vertex edge of the diverter wedge has a generally rounded surface.
- 7. A diverter assembly according to claim 5, wherein at least one of the curved surfaces of the diverter wedge includes at least one port that is connected to an air source for supplying pressurized air through the curved surface.
- 8. A diverter assembly according to claim 5, and further comprising a plurality of belts that confine the signatures therebetween for transporting the signatures along the feed path to one of the plurality of collation paths, wherein said belts are in opposing relation along the feed path of the signatures and in diverging relation prior to the plurality of collation paths.
- 9. A diverter assembly according to claim 1, wherein the grooves in the diverter wedge mesh with the steps in one of the diverter rolls as the diverter rolls and the diverting wedge direct a signature to one of the plurality of collation paths and mesh with the steps in the other diverter roll as the diverter rolls and the diverting wedge direct a succeeding signature to another of the plurality of collation paths.
- 10. A diverter assembly according to claim 1, and further comprising a plurality of belts that confine the signatures therebetween for transporting the signatures along the feed path to one of the plurality of collation paths, wherein said belts are in opposing relation along the feed path of the signatures and diverging relation prior to the plurality of collation paths.
- 11. A sheet diverter for diverting signatures delivered along a feed path to one of a plurality of collation paths, said sheet diverter comprising:a pair of counter-rotating diverter rolls that are adapted to receive signatures therebetween, wherein the diverter rolls reciprocate in a direction that is at least partially normal to the feed path such that the feed path translates between each of the collation paths, each of the diverter rolls including a longitudinal axis that is substantially parallel to the feed path and the other diverter roller and a roll center that is substantially parallel to the feed path and is offset from the longitudinal axis of the respective diverter roll such that each of the diverter rolls rotate eccentrically about the roll center translating the feed path back and forth between the collation paths; a diverter wedge extending into the translating feed path between the diverter rolls to separate the plurality of collation paths, wherein the diverter wedge includes curved surfaces that diverge from a rounded top vertex edge to a base to prevent damaging the signatures as the signatures travel past the diverter wedge; and a plurality of belts that are in opposing relation to confine the signatures therebetween for transporting the signatures along the feed path to one of the plurality of collation paths; wherein the diverter rolls include outwardly extending spaced apart raised steps and the diverter wedge includes spaced apart grooves in the top vertex edge that periodically intermesh with the steps on each of the diverter rolls as the diverter rolls reciprocate.
US Referenced Citations (12)