U.S. patent application number 09/964791 was filed with the patent office on 2002-05-23 for aligner mechanism for a mail handling system.
Invention is credited to Belec, Eric A., Mercede, John J. JR., Salomon, James A., Stefan, Christopher Julius, Supron, Steven A., Wilson, Shae Lynn, Wologodzew, Leo, Yap, Anthony E..
Application Number | 20020060418 09/964791 |
Document ID | / |
Family ID | 23627413 |
Filed Date | 2002-05-23 |
United States Patent
Application |
20020060418 |
Kind Code |
A1 |
Stefan, Christopher Julius ;
et al. |
May 23, 2002 |
ALIGNER MECHANISM FOR A MAIL HANDLING SYSTEM
Abstract
In a device for processing documents being transported
therethrough along a document feed path, an aligner apparatus
comprising: first and second guide walls, each guide wall
positioned parallel to the document feed path and facing the other
guide wall forming an alley along the document feed path in which
the documents are relieved of interdocument forces allowing bottom
edge alignment of the documents with the document feed path, the
guide walls forming a plurality of openings, each opening in the
first guide wall being in alignment with an opening in the second
guide wall; and a trap assembly comprising first and second trap
levers, each trap lever mounted along the document feed path on a
side of the guide wall opposite the document feed path, each trap
lever received by one of the plurality of openings in the guide
walls and each trap lever opposing the other trap lever and
positioned to, when actuated, cause opposing forces on one-another
in order to grab the documents as they move along the feed path in
the aligner apparatus so as to control the gap between the
documents. The trap lever configured with a resilient pad and an
air gap to reduce noise when the lever is actuated and contacts the
document.
Inventors: |
Stefan, Christopher Julius;
(Derby, CT) ; Belec, Eric A.; (Southbury, CT)
; Mercede, John J. JR.; (Easton, CT) ; Salomon,
James A.; (Cheshire, CT) ; Supron, Steven A.;
(Middlebury, CT) ; Wilson, Shae Lynn; (Hamden,
CT) ; Wologodzew, Leo; (Shelton, CT) ; Yap,
Anthony E.; (Danbury, CT) |
Correspondence
Address: |
Alberta A. Vitale, Esq.
Pitney Bowes Inc.
35 Waterview Drive
Shelton
CT
06484-8000
US
|
Family ID: |
23627413 |
Appl. No.: |
09/964791 |
Filed: |
September 26, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09964791 |
Sep 26, 2001 |
|
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09411064 |
Oct 4, 1999 |
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Current U.S.
Class: |
271/256 |
Current CPC
Class: |
B07C 1/04 20130101; B65H
9/06 20130101; B65H 2301/321 20130101; B65H 2301/4452 20130101 |
Class at
Publication: |
271/256 |
International
Class: |
B65H 009/14 |
Claims
What is claimed is:
1. In a device for processing documents being transported
therethrough along a document feed path, an aligner apparatus
comprising: first and second guide walls, each guide wall
positioned parallel to the document feed path and facing the other
guide wall forming an alley along the document feed path in which
the documents are relieved of interdocument forces allowing bottom
edge alignment of the documents with the document feed path,; and a
trap assembly comprising first and second trap levers, each trap
lever mounted along the document feed path on a side of the guide
wall opposite the document feed path, each trap lever opposing the
other trap lever and positioned to, when actuated, to cooperatively
grab and stop the documents as they move along the feed path in the
aligner apparatus so as to control the gap between the
documents.
2. An apparatus as recited in claim 1, wherein first and second
trap levers each comprise: an arm portion, the arm portion
operatively mounted along the feed path; and a head portion, the
head portion configured to pass through one of the plurality of
opening in the guide wall.
3. An apparatus as recited in claim 2, wherein the trap lever
further comprises a trap pad mounted to the head portion forming
gap between the trap pad and the head portion.
4. An apparatus as recited in claim 3, wherein the trap pad is
formed of a resilient material.
5. An apparatus as recited in claim 3, wherein the trap pad is
formed of natural rubber with a coefficient of friction of not less
than about 1.6 on uncoated twenty pound bond paper.
6. An apparatus as recited in claim 1 wherein at least a portion of
the document feed path comprises a transport belt which travels
along an edge of the aligner assembly.
7. An apparatus as recited in claim 1 wherein the first and second
guide walls form sensor openings, each sensor opening in the first
guide wall opposing each sensor opening in the second guide
wall.
8. An apparatus as recited in claim 7 further comprising sensors
mounted along the document feed path for sensing the position of
documents as they passes through the aligner assembly.
9. An apparatus as recited in claim 1 further comprising a sensor
mounted down stream from the aligner apparatus for sensing skewed
documents.
10. An apparatus as recited in claim 1 further comprising an
actuator assembly for operating the trap levers, the actuator
assembly comprising a solenoid, the solenoid coupled to a drive
gear, the drive gear for driving a first and second driven gear,
the first and second driven gears operatively coupled to the first
and second trap levers respectively.
11. An apparatus as recited in claim 1 further comprising: a first
singulator, positioned upstream along the document feed path from
the guide walls and trap assembly, having a first retard assembly
and a first feed assembly disposed opposite to each other along the
document feed path, the first retard assembly and the first feed
assembly cooperating together on a stack of documents being
transported along the document feed path and passing between the
first feed assembly and the first retard assembly to separate and
transport downstream along the document feed path individual
documents from the stack of documents.
12. An apparatus as recited in claim 11 further comprising: a
second singulator, positioned downstream along the document feed
path from the first singulator and trap assembly, having a second
retard assembly and a second feed assembly disposed opposite to
each other along the document feed path, and wherein at times when
a plurality of documents from the stack of documents that are in
overlapping relationship with each other pass through the first
singulator without being separated and are received by the second
singulator the second retard assembly and the second feed assembly
cooperate together on the plurality of documents to separate and
transport individual ones of the plurality of documents downstream
along the document feed path.
13. An apparatus as recited in claim 1 further comprising: first
and second driven vertical belts, each driven vertical belt
positioned above and parallel to the one of the guide walls, facing
the other driven vertical belt and driven in the direction of the
feed path.
14. In a device for processing documents being transported
therethrough along a document feed path, an aligner apparatus
comprising: a trap assembly comprising first and second trap
levers, each trap lever mounted along the document feed, each trap
lever opposing the other trap lever and positioned to, when
actuated, to cooperatively grab and stop the documents as they move
along the feed path in the aligner apparatus so as to control the
gap between the documents; and first and second driven vertical
belts, each vertical belt positioned on a side of the document feed
path and above the trap assembly, forming an alley along the
document feed path in which the documents are relieved of
interdocument forces and are able to align with the feed path.
15. An apparatus as recited in claim 12 further comprising a sensor
mounted down stream from the aligner apparatus for sensing skewed
documents.
16. An apparatus as recited in claim 14 further comprising: a first
singulator, positioned upstream along the document feed path from
the driven vertical belts, having a first retard assembly and a
first feed assembly disposed opposite to each other along the
document feed path, the first retard assembly and the first feed
assembly cooperating together on a stack of documents being
transported along the document feed path and passing between the
first feed assembly and the first retard assembly to separate and
transport downstream along the document feed path individual
documents from the stack of documents.
17. An apparatus as recited in claim 14 further comprising: a
second singulator, positioned downstream along the document feed
path from the driven belts, having a second retard assembly and a
second feed assembly disposed opposite to each other along the
document feed path, and wherein at times when a plurality of
documents from the stack of documents that are in overlapping
relationship with each other pass through the first singulator
without being separated and are received by the second singulator
the second retard assembly and the second feed assembly cooperate
together on the plurality of documents to separate and transport
individual ones of the plurality of documents downstream along the
document feed path.
18. An apparatus as recited in claim 2 wherein the trap lever
further comprises a deflector positioned between the trap head and
the trap arm for deflecting documents.
19. An apparatus as recited in claim 1 wherein each guide walls
forms an opening, the opening in the first guide wall being in
alignment with the opening in the second guide wall and each trap
lever is received by one of the openings in the guide walls.
20. In a device for processing documents being transported
therethrough along a document feed path, an aligner apparatus
comprising: first and second guide walls, each guide wall
positioned parallel to the document feed path and facing the other
guide wall forming an alley along the document feed path in which
the documents are relieved of interdocument forces allowing bottom
edge alignment of the documents with the document feed path; and an
first transport belt for transporting documents into the aligner
assembly and a second transport belt, positioned downstream from
the first transport belt, for transporting documents out of the
aligner assembly, the first transport belts for stopping and
buffering the documents while downstream documents are being
processed.
21. An apparatus as recited in claim 20 further comprising: a first
singulator, positioned upstream along the document feed path from
the guide walls, having a first retard assembly and a first feed
assembly disposed opposite to each other along the document feed
path, the first retard assembly and the first feed assembly
cooperating together on a stack of documents being transported
along the document feed path and passing between the first feed
assembly and the first retard assembly to separate and transport
downstream along the document feed path individual documents from
the stack of documents.
22. An apparatus as recited in claim 21 further comprising: a
second singulator, positioned downstream along the document feed
path from the first singulator and guide walls, having a second
retard assembly and a second feed assembly disposed opposite to
each other along the document feed path, and wherein at times when
a plurality of documents from the stack of documents that are in
overlapping relationship with each other pass through the first
singulator without being separated and are received by the second
singulator the second retard assembly and the second feed assembly
cooperate together on the plurality of documents to separate and
transport individual ones of the plurality of documents downstream
along the document feed path.
23. An apparatus as recited in claim 20 further comprising a sensor
mounted down stream from the aligner apparatus for sensing skewed
documents.
24. An apparatus as recited in claim 22 further comprising a sensor
mounted adjacent to the second singulator for sensing the presence
of documents at the second singulator and a sensor mounted
downstream from the second singulator for sensing documents being
processed downstream from the second singulator.
Description
BACKGROUND
[0001] The processing and handling of mailpieces and other
documents consumes an enormous amount of human and financial
resources, particularly if the processing of the mailpieces is done
manually. The processing and handling of mailpieces not only takes
place at the Postal Service, but also occurs at each and every
business or other site where communication via the mail delivery
system is utilized. That is, various pieces of mail generated by a
plurality of departments and individuals within a company need to
be collected, sorted, addressed, and franked as part of the
outgoing mail process. Additionally, incoming mail needs to be
collected and sorted efficiently to ensure that it gets to the
addressee in a minimal amount of time. Since much of the
documentation and information being conveyed through the mail
system is critical in nature relative to the success of a business,
it is imperative that the processing and handling of both the
incoming and outgoing mailpieces be done efficiently and reliably
so as not to negatively impact the functioning of the business.
[0002] In view of the above, various automated mail handling
machines have been developed for processing mail (removing
individual pieces of mail from a stack and performing subsequent
actions on each individual piece of mail). However, in order for
these automatic mail handling machines to be effective, they must
process and handle "mixed mail." The term "mixed mail" is used
herein to mean sets of intermixed mailpieces of varying size
(postcards to 9" by 12" flats), thickness, and weight. In addition,
the term "mixed mail" also includes stepped mail (i.e. an envelope
containing therein an insert which is smaller than the envelope to
create a step in the envelope), tabbed and untabbed mail products,
and mailpieces made from different substrates. Thus, the range of
types and sizes of mailpieces which must be processed is extremely
broad and often requires trade-offs to be made in the design of
mixed mail feeding devices in order to permit effective and
reliable processing of a wide variety of mixed mailpieces.
[0003] In known mixed mail handling machines which separate and
transport individual pieces of mail away from a stack of mixed
mail, the stack of "mixed mail" is first loaded onto some type of
conveying system for subsequent sorting into individual pieces. The
stack of mixed mail is moved as a stack by an external force to,
for example, a shingling device. The shingling device applies a
force to the lead mailpiece in the stack to initiate the separation
of the lead mailpiece from the rest of the stack by shingling it
slightly relative to the stack. The shingled mailpieces are then
transported downstream to, for example, a separating or singulating
device which completes the separation of the lead mailpiece from
the stack so that individual pieces of mail are transported further
downstream for subsequent processing. In the mailing machine
described immediately above, the various forces acting on the
mailpieces in moving the stack, shingling the mailpieces,
separating the mailpieces and moving the individual mailpieces
downstream often act in a counterproductive manner relative to each
other. For example, inter-document stack forces exist between each
of the mailpieces that are in contact with each other in the stack.
The inter-document stack forces are created by the stack advance
mechanism, the frictional forces between the documents, and
potentially electrostatic forces that may exist between the
documents. The inter-document forces tend to oppose the force
required to shear the lead mailpiece from the stack. Additionally,
the interaction of the force used to drive the shingled stack
toward the separator and the separator forces can potentially cause
a thin mailpiece to be damaged as it enters the separator.
Furthermore, in a conventional separator, there are retard belts
and feeder belts that are used to separate the mailpiece from the
shingled stack. Both the forces applied by the retard belts and the
feeder belts must be sufficient to overcome the inter-document
forces previously discussed. However, the friction force generated
by the retard belts cannot be greater than that of the feeder belts
or the mailpieces will not be effectively separated and fed
downstream to another mail processing device. Moreover, if the
feeding force being applied to the mailpieces for presenting them
to the separator is too great, another potential problem which may
occur is that a plurality of mailpieces (multi-feeds) will be
forced through the separator without the successful separation of
the mailpieces. Another problem that can occur is that the
interdocument stack forces can keep the mailpieces from deskewing
or bottom edge aligning which would prevent the mailpieces from
separating or could also cause an over-height problem in the mail
handling machine.
[0004] Another problem that can occur in the handling of the
mailpieces is that the desired gap between each mailpiece may not
be achieved by the document separators. The gap is important
because it is necessary for timing of down stream processing such
as OCR (optical character recognition). Gap also effects throughput
of the mail handling machine; if the gap is too large, the
throughput of the machine decreases. A buffer between document
singulating apparatus may be used to assist with providing the
proper gap between mailpieces and keep the mailpieces from
colliding which can damage the mailpieces. When a mail handling
machine has two document singulating apparatus, the down stream
document singulating apparatus will function to delay processing of
a mailpiece in a multipiece feed situation such that a next
mailpiece can crash into the mailpiece in the downstream stream
document singulating apparatus. A stopping apparatus can be used to
stop the next mailpiece, this improves the gap between the
mailpieces and subsequently keeps the mailpieces from
colliding.
[0005] In view of the above, it is recognized that large forces are
desirable to act on the mailpieces to accelerate and separate the
mailpieces in a reliable and high throughput manner. However, these
same high forces can damage the mailpieces being processed (i.e.
buckle lightweight mailpieces) and keep the mailpieces from being
bottom edge aligned. Conversely, if the forces used to accelerate
and separate the mailpieces are too small, then poor separation,
lower throughput, and stalling of the mailpieces being processed
will result. Put in another way, thin mailpieces are weak and
require low forces to prevent them from being damaged, while
thick/heavy mail is strong and requires high forces for proper
separation and feeding. The effect is that when the thick/heavy
mail is in the stack higher stack normal forces are created thereby
increasing inter-document forces and requiring higher nip forces at
the separator. Thus, the structure used to separate a stack of
mixed mail must take into account the counterproductive nature of
the forces acting on the mailpieces and be such that an effective
force profile acts on the mailpieces throughout their processing
cycle so that effective and reliable mailpiece separation and
transport at very high processing speeds (such as four mailpieces
per second) can be accomplished without physical damage occurring
to the mailpieces. However, since the desired force profile acting
on a particular mailpiece is dependent upon the size, thickness,
configuration, weight, and substrate of the individual mailpiece
being processed, the design of a mixed mail feeder which can
efficiently and reliably process a wide range of different types of
mixed mailpieces has been extremely difficult to achieve. The mail
handling machine needs a portion which has reduced interdocument
forces which allows the mailpiece to bottom edge align with the
assistance of gravity.
[0006] Furthermore, in achieving the mechanical separation of mail,
the mail handling machine produces mechanical noise. The reduction
of this noise can be difficult to balance with the mechanical
design needs of the machine. Much noise can be produced by the
various mechanisms of mail handling machine including the
separation mechanisms and gap control mechanisms. The noise can
impact the functioning of a mail room environment where the mail
handling machine is being operated. Over a period of time, noise
can induce hearing loss, and cause annoyance and irritation of
workers. Therefore, it is favorable to achieve lower operating
sound pressure levels in the mail handling machine by using
materials and techniques that cure noise problems.
SUMMARY OF THE INVENTION
[0007] It is an object of the invention to provide an aligner
apparatus which bottom edge aligns documents and separates
documents and provides adequate gap between documents for
subsequent processing.
[0008] The above object is met by providing an aligner apparatus
which includes first and second guide walls, each guide wall
positioned parallel to the document feed path and facing the other
guide wall forming an alley along the document feed path in which
the documents are relieved of interdocument forces allowing bottom
edge alignment of the documents with the document feed path, the
guide walls forming a plurality of openings, each opening in the
first guide wall being in alignment with an opening in the second
guide wall; and a trap assembly comprising first and second trap
levers, each trap lever mounted along the document feed path on a
side of the guide wall opposite the document feed path, each trap
lever received by one of the plurality of openings in the guide
walls and each trap lever opposing the other trap lever and
positioned to, when actuated, cause opposing forces on one-another
in order to grab the documents as they move along the feed path in
the aligner apparatus so as to control the gap between the
documents.
[0009] It is yet a further objective to provide an aligner
apparatus which can provide adequate gap between documents while
reducing noise. This object is met by providing a trap subassembly
wherein the trap subassembly comprises trap levers for capturing
the documents as they travel along the document feedpath. Each trap
lever has a head portion which is fitted with a resilient pad which
is attached to the trap arm in a manner that forms a gap between
the head and the pad. The resilient pad and the gap operate to
reduce noise created by the trap arm when actuated.
[0010] Additional objects and advantages of the invention will be
set forth in the description which follows, and in part will be
obvious from the description, or may be learned by practice of the
invention. The objects and advantages of the invention may be
realized and obtained by means of the instrumentalities and
combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate a presently
preferred embodiment of the invention, and together with the
general description given above and the detailed description of the
preferred embodiment given below, serve to explain the principles
of the invention.
[0012] FIG. 1 is a schematic top plan view of a mixed mail feeder
incorporating the inventive aligner mechanism.
[0013] FIG. 2 is an enlarged and detailed top plan view of a
singulator of FIG.
[0014] FIG. 3a is an enlarged and detailed top plan view of an
aligner mechanism of FIG. 1.
[0015] FIG. 3b is an enlarged and detailed perspective view of a
trap lever.
[0016] FIG. 3c is an enlarged and detailed top plan view of the
trap lever.
[0017] FIG. 4 is a perspective view of the actuating assembly and
the trap levers.
[0018] FIG. 5 is a perspective view of an alternate embodiment of
the aligner mechanism of the present invention.
[0019] FIG. 6 is a schematic top plan view of an alternate
embodiment of the aligner mechanism of the present invention.
[0020] FIGS. 7a-c is a simplified schematic top view of an
embodiment of the present invention illustrating mailpiece
positions in an example of a multiple mailpiece feed at the second
document singulating apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] FIG. 1 shows a mixed mail feeder 1 having conventional
framework 2 upon which all of the components of the mixed mail
feeder 1 are mounted. Mixed mail feeder 1 includes a stack advance
mechanism 5 having a continuous conveyor belt 7 mounted for
rotation in a conventional manner about a plurality of pulleys (not
shown) in the direction of arrow "X". Mounted on the conveyor belt
7 in a conventional manner is an upstanding panel 9 which moves
with the conveyor 7 in the direction of arrow "X". In operation, a
stack of mixed mail 11 is placed on the conveyor belt 7 and rests
against the panel 9. The stack of mixed mail includes a lead
mailpiece 13 and a second mailpiece 15. Thus, as the conveyor belt
7 is set into movement, the stack of mixed mail 11 is moved toward
an input feed structure 17. Input feed structure 17 includes a belt
18 which is driven into rotation about a series of pulleys 20, at
least one of which is a driven pulley. Accordingly, as the stack
advance mechanism 5 forces the lead mailpiece 13 into contact with
the belt 18, the lead mailpiece 13 is laterally moved away from
stack of mixed mail 11. Additionally, a driven belt 19 which makes
contact with the bottom edge of the lead mailpiece 13 also assists
in moving the lead mailpiece 13 downstream past a guide mechanism
21 and toward a first document singulating apparatus 23. As shown,
the combination of the stack advance mechanism 5, the input feed
structure 17, and the guide plate 21 help to present the mailpieces
which are removed from the stack of mixed mail 11 into the first
document singulating apparatus 23 in a shingled manner as is more
clearly shown in FIG. 2. The first document singulating apparatus
23 operates to separate the lead mailpiece 13 from the remaining
stack of mixed mail 11 so that only individual mailpieces are
presented to output feeding structure 25 for ultimate processing
downstream to a processing station 26 where each individual
mailpiece has some type of operation (metering, scanning, etc.)
performed thereon.
[0022] Output feeding structure 25 includes a take away rollers 27
and 29 which receive the mailpiece as it exits the first document
singulating apparatus 23 and helps to transport it downstream. The
take away rollers comprise a drive roller 29 and an idler roller
27. The take away idler roller 27 is spring loaded by spring 30 and
is moveable toward and away from the take away drive roller 29 to
accommodate different mailpiece thicknesses. FIG. 3a is an enlarged
and detailed top plan view of a aligner mechanism of FIG. 1 and
illustrates a aligner station 31 consisting of two guide walls 33,
35 which help to direct the individual mailpieces in a vertical
fashion to ensure that they are aligned on their bottom edge prior
to transport past a second guide plate 37 and into a second
document singulating apparatus 39. Subsequent to passage through
the second document singulating apparatus 39, the individual
mailpieces are transported into a second set of take away rollers
41 which transport the individual mailpieces to the processing
station 26. The second set of takeaway rollers 41 has the same
structural components as the first set of take away rollers 25.
[0023] The second singulating apparatus 39 has the same structural
components as the first singulating apparatus 23 and can be driven
by an independent drive system similar to that used for first
singulating apparatus 23. The use of the redundant singulating
apparatus structure improves the reliability of separating
individual documents from each other since, if a multi-feed does
pass through the first singulating apparatus 23 it is likely that
the second singulating apparatus 39 will effectively separate the
documents of a multi-feed.
[0024] In the aligner station 31, the mailpieces are driven along
their bottom edges by a transport belt 42. The gap D between the
guide walls 33, 35 allows that the frictional forces between the
mailpieces are almost nonexistent. Since the frictional forces tend
to cause mutli-mailpiece feeds, this configuration helps to prevent
multi-mailpiece feeds from occurring at the second singulating
apparatus 39. Furthermore, the aligner station acts as a buffer
between first and second document singulating apparatus, allowing
mailpieces to deskew or register onto the transport belt 42.
Subsequent to passage through the second document singulating
apparatus 39, the individual mailpieces are transported into the
second set of take away rollers 41 which act on the mailpieces to
transport the mailpieces to the processing station 26.
[0025] In the preferred embodiment, the guide walls 33, 35 are
separated from each other on each side of the mailpiece feed path
51 by a distance of approximately 28 millimeters. This allows for
the passage of 3/4" thick mailpieces. However, other mailpiece
thickness specifications and distances may be used. The minimum
distance may be determined by the specification of the maximum
width of mailpieces to be passed along the document feed path.
Additionally, the distance is determined by the minimum angle that
the smallest mailpiece would have with respect to the transport
belt 42 when leaning against guide walls 33, 35. The angle, if too
small, would cause the mailpiece to lean below the mailpiece
sensors 105. This spacing would also allows most multi-feeds which
leave first document singulating apparatus 23 to be transported
through aligner station 31 without any large inter-document forces
existing between the mailpieces because no significant normal feed
force is present when the mailpieces are fed by belt 42. It should
be noted that in an alternate embodiment only one document
singulating apparatus upstream from the aligner station 31 may be
used in the mixed mail feeder 1.
[0026] Additionally, antistatic brushes 121 (shown in FIG. 3a) may
be mounted onto the guide walls to help prevent lightweight, static
prone mailpieces such as mailpieces wrapped in wrapping sold under
the trademark TYVEK.RTM. (manufactured by Dupont), envelopes and
postcards from clinging to the walls. The leading edges of the
guide walls 33, 35 are flared outward to minimize catch points. To
provide jam clearance, one guide wall may be hinged to open at, for
example, 45 degrees with positive stops at full close and full
open. The minimum length of the aligner station 31 is governed by
the maximum size of the mailpieces to be handled by the mixed mail
system. That maximum length of the mailpieces is 14 inches and
therefore the aligner station 31 must be at least 14 inches in
order to provide a distance sufficient enough to provide deskewing,
between the two document singulating apparatus 23, 39. Furthermore,
the length must be additionally increased to allow the mailpieces
traveling through the aligner station 31 time to deskew or bottom
edge align with the transport belt 42.
[0027] The aligner station 31 may include a trap subsystem 100
which provides gap enforcement between mailpieces. The gap is
important because the mail handling machine may need time for
processing that happens down stream in the processing station 26,
such as OCR processing. Additionally, proper gap affects throughput
of the mail handling machine. Gap is also helpful in a situation
where there is a multifeed going into the second document
singulating apparatus 39, as described below. The trap 100 allows
the transport belt 42 to remain in constant motion while an
interpiece gap is being maintained or lengthened instead of
attempting to achieve the gap by stopping and starting the
transport belt 42 which would stop all the mailpieces on the belt
instead of just the mailpieces between which a larger gap is
desired.
[0028] The trap subsystem 100, illustrated in FIG. 3a, comprises
two trap levers 101, 103 which are actuated in order to grab a
mailpiece as it moves through the aligner station 31. The actuation
is based upon timing information from feed path sensors 105 which
are mounted along the feed path. Each sensor 105 may be, for
example, a photo electric sensor for detection of light, which when
blocked indicates that a mailpiece is on the transport belt in the
area of the sensor 105, and when not blocked, indicates that there
is no mailpiece in the area of the sensor. The sensor
configurations for the various embodiments are example
configurations, other configurations may be used as may be
determined by one of ordinary skill in the art. The guide walls 33,
35 may have openings which accommodate the sensors. The timing for
actuating the trap levers may be determined by one of ordinary
skill in the art; however, in the preferred embodiment, the trap
levers 101, 103 may actuate any time too small a gap exists between
mailpieces and that gap can not be widened by some other upstream
mechanism in the mail handling machine such as the take away
rollers 27, 29 of the output feed structure 25. In the event that
the trap subassembly 100 is unable to top the mailpiece in time,
the second document singulating apparatus 39 would act to help
enforce the gap control. Each trap lever 101, 103, illustrated in
FIGS. 3a, 3b and 3c, comprises an arm portion 107 and a head
portion 109.
[0029] A trap pad 111 is mounted on the head portion 109 in a
configuration which forms an air gap 113 between the trap pad 111
and the head portion 109. In the preferred embodiment, the trap pad
111 may be formed of a material such as natural rubber with a
coefficient of friction not less than 1.6 on uncoated twenty pound
bond paper. The trap pad 111 functions to provide adequate friction
to stop large and/or heavy mailpieces within the aligner station
31. The trap pad 111 material functions while being exposed to
various materials and contaminates which effect the trap pad's
coefficient of friction. Furthermore, the resilient material
forming the trap pad 111 and the air gap 113 function to minimize
noise when trap levers 101, 103 actuate and grab a mailpiece. The
trap pad 111 and air gap 113 also prevent rebound of the trap
levers 101, 103 after impact which can cause the mailpiece to
escape the trap subsystem 100. Additionally, the air gap 113 acts
to reduce noise by decelerating the trap levers 101, 103 prior to
final impact with the mailpieces. This noise reduction helps to
make the mail handling machine more tolerable in a work
environment.
[0030] The trap subsystem 100 may further comprise a deflector 115
which deflects mailpieces as they move through the aligner station
31. The deflector 115 is configured to prevent the mailpieces from
becoming hung up on the trap head portion 109.
[0031] FIG. 4 illustrates an actuating assembly 117 for trap levers
101, 103. The trap levers 101, 103 can be actuated by the actuating
assembly 117 (which can be mounted under deck 2 using bracket 119)
which comprises an electromagnetic solenoid actuator or brushless
torque actuator (BTA) 120 attached to a drive gear 122 which drives
two driven gears 124, 126. A microprocessor 131 controller may be
used to control the actuation of the BTA 120 and other gap control
apparatus. The two driven gears 124, 126 are coupled to a drive
shafts 128a, 128b respectively, and each drive shaft 128a, 128b is
coupled to trap lever 101, 103 respectively. The trap levers 101,
103 are mounted such that in the resting position, a gap E
(illustrated in FIG. 4) which is slightly wider than the thickest
anticipated mailpiece is present between the trap levers 101, 103
to ensure proper actuation time and prevent mailpieces from hitting
the trap levers 101, 103 as they travel through the aligner station
31. The gears 122, 124, 126 are designed with high tolerances which
provide for less resistance of the driven gear 124, 126 and less
friction during operation which causes more efficient operation and
reduces noise.
[0032] In an alternate embodiment (illustrated in FIG. 5), instead
of guide walls, two vertically oriented transport belts 32, 36
positioned parallel to and on each side of the aligner station 31
above the trap subassembly 100. The vertically oriented belts are
driven in the direction of the feed path and serve to move the
mailpieces along the paper path as well as provide support for the
mailpieces in a similar fashion to the guide walls 31, 35.
[0033] In another alternate embodiment (illustrated in FIG. 6), the
aligner station 31 comprises guide walls 33, 35 and first and
second transport belts 42a, 42b. The first transport belt 42a
transports mailpieces from the first set of takeaway rollers 25
into the aligner station 31. The second transport belt 42b is
positioned downstream from the first transport belt 42a, and
transports documents out of the aligner assembly. The first
transport belt stops the documents while downstream documents are
being processed. An example of the first transport belt 42a
stopping upstream mailpieces follows. When a multiple mailpiece
feed is at the second document singulating apparatus 39, a
singulator sensor 105c is blocked. When a lead mailpiece is
singulated and travels downstream to the second set of takeaway
rollers 41, the singulator sensor 105c remains blocked by other
mailpieces in the multipiece feed. The lead mailpiece, positioned
at the second set of takeaway rollers 41 blocks the take away
sensor 105d. When both sensors 105c, 105d are blocked, the first
transport belt 42a stops transporting upstream mailpieces and the
second transport belt 42b continues feeding mailpieces into the
second singulating device 39 until the multipiece feed is cleared.
After the multipiece feed is cleared, the first transport belt 42a
resumes the upstream mailpieces.
[0034] The following is an example of the operation of the aligner
station 31 and trap subassembly 100 of the embodiment of FIG. 1, in
handling a multiple mailpiece feed at the second document
singulating apparatus 39 as illustrated in FIGS. 7a-c. FIGS. 7a-c
are simplified schematic top views illustrating mailpiece positions
at first, second and third successive time increments respectively.
In FIG. 7a, at the first time increment, two mailpieces, mailpiece
A and mailpiece B are fed to the second document singulating
apparatus 39, mailpiece A is separated from mailpiece B in the
second document singulating apparatus 39. The trail-edge of
mailpiece B waits in the aligner station 31. At the second time
increment, illustrated in FIG. 7b an entry sensor 105b for second
document singulating apparatus 41 sees the trailing edge of
mailpiece B, then mailpiece C is fed into the aligner station 31.
The sensors 105 in the area of the aligning station monitor the gap
between the trail-edge of mailpiece B and the lead edge of
mailpiece C. When the gap between the trail and lead edge of these
two mailpieces becomes too small, which is indicated when only one
sensor is not blocked (as explained above), and mailpiece C is
stopped by the trap subsystem 100 in the aligner station 31. FIG.
7c illustrates the third time increment which shows recovery of
normal operation of the mixed mail feeder by singulation of
mailpieces A and B and feeding mailpiece C into the second document
singulating apparatus 39.
[0035] The operation of trapping the mailpieces occurs generally,
when only one sensor is not blocked; when this occurs upstream mail
flow is stopped. The upstream mail flow can be stopped by take away
rollers 25 or the trap subsystem 100 depending upon the position of
the upstream mail when too small of a gap is sensed by sensors 105.
When the trap subsystem 100 is actuated, all upstream mail flow is
stopped. A condition that can cause actuation of the trap subsystem
100 is when a mailpiece is delayed from feeding out of the second
document singulating apparatus 39 and another mailpiece is at the
trap subsystem and only one sensor is not blocked. A condition that
can cause the stopping of mailpiece(s) by the take away rollers 25
is when longer mailpieces are in a multipiece feed situation at the
second document singulating apparatus 39 and the trail edge of one
or more of those mailpieces is blocking sensors in the aligner
station 31 such that only one sensor is not blocked, the take away
rollers 25 stop the upstream mailpiece(s).
[0036] In the situation where the mailpiece continues to be skewed
after passing through the aligner station 31, an over-height sensor
105a (shown in FIG. 1) mounted downstream from the aligner station
31 at an overheight position will sense the skewed mailpiece and
stop the mail handling machine so that the mailpiece can be
manually cleared from the feed path. The over-height sensor 105a
can also sense mailpieces that are not skewed but are above the
maximum height requirements of the mail handling machine.
[0037] Finally, the aligner station 31 significantly improves the
separation capability of the singulating apparatus 39 by reducing
the inter-document forces between the large and small mailpieces
via its bottom edge transport and overall configuration such that
separation is more easily achieved. The aligner station 31 also
improves separation of mailpieces thus helping to prevent
mailpieces from colliding and becoming damaged. Additionally, the
aligner station 31 provides mailpiece edge alignment while reducing
noises such as inter-document noises and mechanically created
noises by providing an improved trap lever with an airgap 113 and a
trap pad 111 of resilient material and also by providing
deceleration of the trap lever 101, 103 prior to final impact with
the mailpiece. Noise is also reduced by providing an actuating
assembly 117 with high design tolerances such that the gear centers
are accurately controlled.
[0038] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details, and
representative devices, shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims. For example while the preferred embodiment is
described in connection with a mail handling machine, any apparatus
for handling mixed or same sizes/thicknesses of articles can
utilize the principles of the invention.
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