High speed document stacking assembly

A document processing arrangement transporting checks or like financial documents at a prescribed nominal speed along a track, terminated by sort-pockets, each with an associated diverter plus a guide assembly for guiding and driving a so-diverted document into its pocket, the guide comprising an inject roll to accelerate the document, plus an arm-assembly coupled to rotate with the roll and including an arm for guiding a so-injected document toward its position in the pocket-stack; this roll and arm assembly being arranged to rotate the arm away from its stack each time a document is entering, and also to be spring-driven to return the arm toward its stack.

This invention relates to document transport, sorting, and stacking 
equipment, and especially to an assembly for stacking documents in a sort 
pocket. 
BACKGROUND, FEATURES 
Workers are aware that present-day high speed document sorting arrangements 
are under scrutiny to solve problems that seem to persist; for example 
their rather high noise level and their many complicated expensive parts. 
This is certainly the case when stacking documents in a sort-pocket at a 
"high" rate (e.g. several hundred checks per minute or faster). 
BACKGROUND, FEATURES 
Workers in the field of high-speed document sort/processing, such as in the 
sorting of bank checks and like financial instruments, know that the art 
requires the use of machines and systems capable of moving and processing 
very large volumes of documents at up to thousands of documents per 
minute, while performing multiple and inter-related operations as the 
document are transported. Such operations can include, (but are not 
limited to), printing upon the documents, reading data previously encoded 
thereon by a variety of processes, recording an archival image of the 
document by photographic or electronic-imaging techniques, and other 
processes. 
Workers understand that, when sorting such volumes it is vital that an 
individual document be diverted and stacked in a sort-pocket as simply and 
quietly as possible. 
This invention addresses these and related problems; e.g., teaching a 
sort-pocket with inject means coupled to guide-arm means wherein these 
means are conjunctively rotated towards a "full-pocket position" as each 
document enters their pocket, then released to be spring-urged and let the 
arm means resiliently depress the top document. 
This invention teaches a novel sort-pocket stacking assembly that reduces 
noise, complexity and cost, while automatically aiming documents to the 
"top" of a stack in a sort-pocket. 
This invention minimizes the cited shortcomings and includes a stacker 
assembly that can: 
--accommodate high-capacity pockets, yet in a small footprint. 
--handle a wide variety of document-lengths (e.g., checks 4.50-9.25"); 
--reduce number of parts, cost and noise by not using an "auger system" or 
"pull-in rollers" (with associated belts, etc.) to push the document stack 
aside; 
--immediately position a document at, or close to, its final resting 
position in the pocket--by differently-aiming each incoming document 
toward its desired position (rather than by directing every document to a 
common pocket position and then moving it aside to make room for the next 
document); and 
--allow an operator to tune the assembly to various document types; e.g. by 
adjusting return spring (e.g. for documents which are "abnormal", e.g. as 
to weight, height-aspect ratio or "grain": note recycled paper has no 
grain and reacts very differently). 
As a feature hereof, such a sort-pocket stacker is preferably provided by 
coupling a guide-in arm assembly to inject roller means whereby the roller 
means automatically throws the assembly towards a full-pocket position as 
it injects a document and then lets it fall to the top of the 
stack--whereat the incoming document is aimed. 
Thus, it is an object hereof to address (at least some of) the 
aforementioned problems, and to provide the herein-cited advantages and 
functions. A related object is to provide such an automatic, 
"variable-aiming" stacker for a sort-pocket. 
The methods and means discussed herein, will generally be understood as 
constructed and operating as presently known in the art, except where 
otherwise specified; with all materials, methods and devices and apparatus 
herein understood as implemented by known expedients according to present 
good practice.

PREFERRED EMBODIMENT 
FIG. 1 may be understood as depicting in schematic plan view, an array of 
sort pockets (six rear pockets SP-R; six front-pockets SP-F) integrated 
into a high-speed check processing machine (e.g. at the end of check 
transport/processing track, with checks injected at IN, to be selectively 
diverted to an assigned sort-pocket (e.g. P-1) under control of a 
pocket-diverter unit (not shown, but well known in the art). 
FIGS. 2-5 depict a preferred embodiment: a novel stacker assembly, 
generally comprising an "inject-reaction-guide" (arm) assembly AA 
(comprising an arm A, with tip J, integral with and supported on arm-block 
AB), together with a cooperating stack-inject-drive roller B plus 
associated stack-pulley E and belt D for driving roller B, along with main 
drive pulley F and housing/support-block G for rotating driver-pulley E, 
plus idler-roller C cooperating with inject roller B to engage, and 
drive-in entering documents. 
Arm "A" is loaded clockwise (see plan view, FIGS. 1, 5) by an operator 
adjustable spring A-S adapted to urge tip J down atop the stack. Spring 
A-S is mounted on bearings on the shaft FS (FIGS. 3, 4C) for drive pulley 
"F". Pulley F is bearing-mounted to rotate in "turn-guide" housing "G". 
The centerline of drive pulley "F" is in line with "columnating" -idler 
"C" which is independently rotatingly-mounted and is spring loaded against 
pocket-inject drive roller "B" (e.g. see spring C-S, FIG. 3). Roller "B" 
is bearing-mounted on a shaft "L", which is mounted on block AB (in 
bearing therein; see (FIGS. 2-4) and is driven by a belt "D" which is, in 
turn, driven by pulley "E" coupled drivenly on shaft FS (for drive pulley 
"F"). 
Thus, on main shaft FS, pulley F is affixed to rotate shaft FS; and drive 
pulley E is affixed on FS to be rotated thereby, and to thereby rotate 
roller B in synchronism with FS [except that, pulley E and gearing for 
roller B, are dimensioned to cause B to rotate faster than (e.g. 1.3x) the 
rotational velocity of shaft FS). 
Roller B is mounted to rotate freely (in bearings) on a shaft L affixed on 
(e.g., lead-screw into) block AB. Arm A is projected from a pillar 
extension AC which, in turn, projects up from block AB. Roller "B" is 
bearing mounted on shaft "L" (mounted on blocks AB, AC, see FIG. 3) and is 
driven by belt "D" (which in turn is driven by pulley "E", mounted on the 
end of shaft FS). 
Block AB is mounted on main shaft FS to rotate freely thereon, being 
loosely captured (positioned) between the upper/lower arms of 
housing/support block G. Preferably, block AB includes extension AC (e.g. 
FIG. 3A) and is molded to integrate AC and arm A in a single unit. Return 
spring A-S urges this unit so arm A is urged down-into its pocket versus 
the documents therein. (e.g. see arrow FIG. 4C). Block G is affixed to the 
machine frame and locates shaft FS to allow free rotation of FS, while 
positioning-block AB including AC and arm A thereof, so that arm A is 
normally disposed to sweep documents across the floor of its respective 
sort pocket (see below), and so that inject-roller B is positioned to 
receive documents diverted to that pocket as known in the art (divert 
means not shown, but well known in the art). 
Articulated arm tip "J" pivots freely about a pin "K" on the end of arm "A" 
and is spring-loaded to be urged clockwise (as seen in FIGS. 1, 3, 5: J-S; 
also see arrow FIG. 4C) and to resiliently aim the leading-edge of 
injected documents down into its pocket, while resiliently pressing 
lightly down on the top of the stack. 
A wave spring "H" is mounted to arm "A" and acts to resiliently depress the 
trailing-edge of such injected documents, while freely allowing their 
leading-edge to pass unaffected. 
Drive pulley "F" is belt-driven off a main stacker transport drive (not 
detailed). The pulley ratios of the system will, preferably, be selected 
to drive pulley "B" at a faster surface velocity (e.g., here 20 to 30 
inches per second faster) than the main transport (which acts along IN 
direction, FIG. 1). The actual velocity should be determined by testing, 
as known in the art; e.g., matching system inertias, document types and 
sizes, and spring forces and rates. 
FIG. 3 shows an exploded elevation of elements of this assembly, with 
elements cut-away in FIG. 3A; while FIG. 4A shows a side view thereof (and 
front elevation in FIG. 4D), with FIG. 4B showing an isometric perspective 
and FIG. 4C a plan view. 
FIG. 5 shows several stacker pockets (P-1, etc.), each with a respective 
inject-guide assembly AA: e.g. see arm A in the "full"-position (P-1) in 
the "empty" position (P-4), in the "almost-empty" position (P-2) and in 
the "partial full" (P-3) position. A sample document d-1 is shown entering 
"almost empty" pocket P-2 in FIG. 5. The trailing portion of document d-1 
can be seen still engaged by a main transport roller pair, "M", "N", at 
the same time that its leading portions are engaged by rollers "B", "C" 
for injection into pocket P-2. 
Since rollers "B", "C" are trying to drive document d-1 (into P-2) faster 
than rollers "M", "N", then d-1 will act as a slight "drag", rotating B 
counterclockwise (see arrow). And, since the rest of arm assembly AA 
(including block AB and arm A) is coupled to rotate with B, then they too 
will rotate counter-clockwise (in plan view--see direction of reaction 
arrow)--, to thereby clear a path for the incoming document and throw A, J 
toward the "full-pocket" extreme, then let A, J fall back (clockwise, 
being spring-urged by A-S) until J contacts the top document in this 
pocket. (e.g. in P-2, it falls onto d-1 after d-1 is inserted into P-2). 
Here, it will be understood that rollers B, C are thereby positioned to 
aim document d-1 toward its ultimate position in P-2 (e.g. note 
"aim-paths" in FIG. 5 for pockets P-1, P-4). 
FIG. 1 is a plan view of a 12-pocket Unisys DP500 check-stacker module, 
with each pocket fitted with a document-inject/reaction-guide arm assembly 
AA as per the above described embodiment. This identical type of assembly 
will accommodate all pockets, front and rear. This novel (stacker module) 
design will provide higher document capacity than for present conventional 
"large capacity" units (e.g., for the Unisys DP1800 Imaging Stacker); yet 
it keeps within the "footprint" of present "low capacity" units (e.g., the 
Unisys DP500 standard stacker). Further, it retains the 
short-document-handling capability (e.g. 4.5") of "standard" 
stacker-means. It is also simpler and "quieter", with a relatively few 
simple parts needed. 
--Functional description (e.g., see FIGS. 1-5): 
The mechanism that arms the document (e.g. d-1, FIG. 5) includes 
inject-drive roller B placed at the pocket entry. Inject roller B is 
mounted on the pocket's inject-guide mechanism AA (including assembly AB, 
AC, arm A) which is arranged to pivot on shaft FS (i.e., pivots about the 
centerline of columnating idler roller C versus counter-urge of spring 
A-S, along with assembly A, AC, AB). Arm A is designed such that the 
"aim-line", (or tangent at the intersection of the idler C and drive 
roller B; this defining the inject-path (inject-aim-path) of the document 
into a pocket) is generally parallel to the length of arm A, and will 
shift in accordance with how full its pocket is. For instance, note, in 
FIG. 5, the aim-path for "Full" pocket P-1 versus that for "Empty" pocket 
P-4; also note spring-reaction arrows. 
Arm A will be seen to be pivoted, as each document enters, about shaft FS 
(e.g. from an "empty-pocket" position, as for pockets P-2, P-4 in FIG. 5), 
to a "full-pocket" position (e.g., as for pocket P-1). Thus, as a pocket 
fills, this tangent ("aim line") is shifted to the position required by 
the next document, since arm A, (tip J) falls back to rest on the stack 
top. As successive documents enter a pocket, the "rest"-position of arm A 
(and roller B) is thus indexed back (versus spring) by the thickness of 
the document so the "aim-point" for the next document is shifted toward 
this next document's ultimate position in the pocket. 
Roller B runs at a higher (surface) velocity than the main transport; 
and--as each document enters, this speed differential is used to swing B, 
(about C) and carry arm A back, to allow the document a free path to the 
back of the pocket. Roller spacing (B/C vs. M/N) is such that an injected 
document will still be driven by the (lower-speed) main-transport roller 
pair (e.g., M/N), when its leading edge is engaged by inject rollers B, C. 
Since the main-transport rollers M, N, are driving the document at the 
lower speed, the higher-speed rollers B, C mounted on arm assembly AA will 
"try to climb the document," causing assembly AA (including block AB, and 
arm A) to pivot in the reaction-direction (arrows in P-2, FIG. 5) and 
clear a path (i.e., shift back in the pocket) for the incoming document. A 
return spring (AS in FIG. 3) then returns arm A until tip J lightly 
contacts the top document, thus placing arm A in position, to aim the next 
incoming document toward the stack-top. 
The inertia of arm mechanism AA and the spring force are balanced to 
control how far, and how fast, the arm pivots back, and how rapidly it 
returns to depress the document stack (via tip J). The initial spring 
force is operator-adjustable (as known in the art) to allow tuning of each 
individual pocket to match the contemplated document size, weight and 
condition for that pocket. 
The two-piece spring loaded, articulated arm A changes its contact point on 
the pocketed documents as the pocket fills up. This eliminates the effect 
of the tip J (on arm A) moving toward the leading edge of the documents as 
the pocket fills up, while also automatically shifting the contact point 
towards the trailing edge as the pocket fills up. It also helps to hold 
the trailing edge away from the leading edge of the next incoming 
document. 
Tip J of arm A is designed to act as an "inch worm" as the arm returns 
after a document is pocketed. This serves to help ensure that a document 
will reach the end (back wall, ew opposite roller B, see FIG. 5) of the 
pocket. 
Wave spring H on arm A will help ensure a clear path for the incoming 
document. This spring is light enough so the energy of the incoming 
document will deflect the spring out of the way without essentially 
deflecting the document. Arm A also preferably carries a magnet assembly 
to actuate a "Hall effect" switch and so signal "full pocket". 
The pockets have a "sloping floor" P-S (sloping "down" from full-side to 
empty-side, to help gravity-urge documents "down"-in a pocket, along with 
tip J against each pocket's "back-wall" bw [against which first-in 
document rests, e.g., see FIG. 5). And floor P-S "leans away" from the 
entrance zone to cause the document stack to lean (fall) away from 
incoming documents (under gravity, as workers will realize) toward bw. 
The foregoing (and other, like) "stacker" embodiments will be seen as 
advantageously minimizing cost, assembly time, noise, etc., and as better 
accommodating various document sizes, while quickly reacting and steering 
successive documents to an optimal position in a pocket. 
Conclusion 
It will be understood that the preferred embodiments described herein are 
only exemplary, and that the invention is capable of many modifications 
.and variations in construction, arrangement and use without departing 
from the spirit of the invention. 
Since modifications of the invention are possible, for example the means 
and methods disclosed herein are also applicable to the sort-pockets of 
other sort/stack arrangements, as well as to other related stacking 
arrays; and it will be understood that the present invention is also 
applicable for enhancing other related sheet-advance arrangements (e.g., 
document sorters, mail sorters, copiers, page feeders for printers, punch 
card sorters, envelope stuffing machines, money feeders and transports in 
automatic teller machines). 
Examples given above of other possible variations of this invention are 
merely illustrative. Accordingly, the present invention is to be 
considered as including all possible modifications and variations within 
the scope of the invention as defined by and set forth in the appended 
claims.