U.S. patent application number 11/254516 was filed with the patent office on 2007-04-26 for vertical mail piece stacker.
This patent application is currently assigned to Pitney Bowes Incorporated. Invention is credited to Michael S. Doery.
Application Number | 20070090590 11/254516 |
Document ID | / |
Family ID | 37984623 |
Filed Date | 2007-04-26 |
United States Patent
Application |
20070090590 |
Kind Code |
A1 |
Doery; Michael S. |
April 26, 2007 |
Vertical mail piece stacker
Abstract
A mail piece stacker system includes a back wall and a side
wall. A platform is mounted adjacent to the back wall and side wall
and is moveable in a vertical direction. The platform is adapted to
support a stack of mail pieces, such as mail pieces, and has means
connected to the platform to position the platform in a first
vertical position when no mail pieces are on the platform and to
position the platform in a different vertical position lower than
the first vertical position when mail pieces are on the platform.
The platform may be positioned at an acute angle with respect to
the back wall and the side wall to help in registering mail pieces
being stacked on the platform. The stacker may employ the method of
moving mail pieces seriatim onto a platform. The platform is
moveable in a vertical direction and is moved in a downward
direction as mail pieces are stacked on the platform. The movement
is such that the vertical level of the stacker platform is adjusted
as mail pieces are stacked on the platform so that the top surface
of the topmost mail piece is substantially adjacent the vertical
position of the platform when no mail pieces are on the
platform.
Inventors: |
Doery; Michael S.; (Monroe,
CT) |
Correspondence
Address: |
PITNEY BOWES INC.;35 WATERVIEW DRIVE
P.O. BOX 3000
MSC 26-22
SHELTON
CT
06484-8000
US
|
Assignee: |
Pitney Bowes Incorporated
Stamford
CT
|
Family ID: |
37984623 |
Appl. No.: |
11/254516 |
Filed: |
October 20, 2005 |
Current U.S.
Class: |
271/213 |
Current CPC
Class: |
B65H 31/3063 20130101;
B65H 2601/325 20130101; B65H 2701/1916 20130101; B65H 2405/11152
20130101; B65H 31/14 20130101 |
Class at
Publication: |
271/213 |
International
Class: |
B65H 31/04 20060101
B65H031/04 |
Claims
1. A stacker system, comprising: a back wall and a side wall; a
platform adapted to support a stack of mail pieces, said platform
mounted adjacent said back wall, and said side wall, said platform
moveable in a vertical direction; and, a means connected to said
platform to position said platform in a first vertical position
when no mail pieces are on said platform and to position said
platform in a different vertical position lower than the first
vertical position when mail pieces are on said platform.
2. A stacker system as defined in claim 1, wherein said platform is
positioned with respect to said back wall to form an acute angle
such that mail pieces on said platform tend to move toward said
back wall.
3. A stacker system as defined in claim 2, wherein said platform is
positioned with respect to said side wall to form an acute angle
such that mail pieces on said platform tend to move toward said
sidewall.
4. A stacker system as defined in claim 1, wherein said platform is
positioned with respect to said back wall to form an acute angle
and said platform is positioned with respect to said sidewall to
form an acute angle such that mail pieces on said platform tend to
move toward said back wall and tend to move toward said side
wall.
5. A stacker system as defined in claim 4, including guide members
for guiding mail pieces onto the platform.
6. A stacker system as defined in claim 5, wherein said first
vertical position of said platform is at a height to receive mail
pieces moved past the guide members and onto said platform.
7. A stacker system as defined in claim 1, wherein said means is a
spring selected such that vertical downward movement of said
platform under the weight of a mail piece is a distance
substantially equal to the thickness of said mail piece so that the
topmost mail piece of a stack of mail pieces on said platform is
substantially adjacent to said first vertical position.
8. A stacker system as defined in claim 7, wherein said platform is
positioned with respect to said back wall to form an acute angle
such that mail pieces on said platform tend to move toward said
back wall.
9. A stacker system as defined in claim 7, wherein said platform is
positioned with respect to said side wall to form an acute angle
such that mail pieces on said platform tend to move toward said
sidewall.
10. A stacker system as defined in claim 7, wherein said platform
is positioned with respect to said back wall to form an acute angle
and said platform is positioned with said sidewall to form an acute
angle such that mail pieces on said platform tend to move toward
said back wall and tend to move toward said side wall.
11. A stacker system as defined in claim 1, wherein said platform
is mounted to a moveable belt.
12. A stacker system as defined in claim 11, wherein said platform
includes a first platform segment and a second platform
segment.
13. A stacking system as defined in claim 12, wherein said means is
a motor connected to said moveable belt.
14. A stacker system as defined in claim 1, further comprising a
lock mechanism for locking said platform from vertical
movement.
15. A stacker system as defined in claim 14, further comprising a
pivot connected to enable said platform to be moved for unloading a
stack of mail pieces on said platform into a mailing tray.
16. A stacker system as defined in claim 7, wherein said spring is
tunable to accommodate different size mail pieces.
17. A method for stacking mail pieces, comprising the steps of:
moving mail pieces seriatim onto a vertically moveable platform;
and, adjusting the vertical level of said platform such that said
topmost mail piece surface remains substantially adjacent the
vertical position of said platform without mail pieces on said
platform.
18. A method for stacking media items as defined in claim 17,
wherein said vertically moveable platform is adjacent a back wall
and moving said mail pieces includes the step of moving a lead edge
of each of said mail pieces to strike said back wall and thereafter
move downward toward said platform.
19. A method for stacking mail pieces as defined in claim 18,
wherein said vertically moveable platform is adjacent a side wall
and moving said mail pieces includes the step of moving said mail
pieces toward said side wall.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to mail piece handling
equipment and more particularly to a vertical mail piece stacker
system.
BACKGROUND OF THE INVENTION
[0002] Various mail handling equipment, such as mailing machines,
inserters and folders, employ mail piece stackers. Various
arrangements of stackers have been implemented in mail handling
equipment and also in copiers. These include auger-type stackers,
drop-type stackers, and bins used to catch copy sheets in a copier
output station.
[0003] In certain mail creation machines finished mail pieces are
moved into a bin. Although the equipment operates satisfactorily,
the employment of large bins can result in mail pieces ending up in
a haphazard pile that may not preserve the order of the output of
the equipment. Preserving the order the mail pieces can be
important to maintain a lower postal cost for some mailings where
quantity discounts are provided when mail is grouped by postal
codes. Moreover, reducing the size of the bin may help in
minimizing the problem of haphazard organization of the mail
pieces, however, the operator must empty the bin at much more
frequent intervals. Another approach has been to deposit the
finished mail pieces in a horizontal conveyor (a tab-type stacker)
in a shingled arrangement. While this approach tends to preserve
the output order of the mail pieces and the mail is generally
organized in a neat grouping, such an arrangement takes up a lot of
floor space and can be very expensive. The stacking of copy sheets
has been employed in copier output stations where copy sheets are
moved onto a platform which is lowered by electromechanical
motorized means. The platform is lowered so that the distance
traveled by the copy sheets to the top of the stack is
minimized.
[0004] It is desirable in media stacking systems to provide stacks
that are neat, preserve the output order of the mail pieces from
the media handling equipment, such as the inserters, folders and
the like, and also allow unloading while the equipment is running.
It is desirable in stacking systems to facilitate the unloading and
to facilitate easy transport of the mail pieces from the stacker,
such as in a mailing tray for mail pieces.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide a
flexible stacker that will not require a long drop into a single
bin design and will help preserve the output order from mail pieces
handling equipment in a neat stack.
[0006] It is a further object of the present invention to provide a
stacker configuration that facilitates user unloading of the
stacker.
[0007] It is yet another object of the present invention to provide
an effective vertical stacker that takes up a small footprint and
also stacks mail pieces neat enough to allow the operator to
transfer the mail pieces in an ordered stacking such as to a mail
piece mailing tray employed by the United States Postal Service
(USPS) and other posts.
[0008] It has been discovered that a vertical, or near-vertical,
stacking arrangement can be employed which can receive or catch,
for example, mail pieces near a mailing machine exit and have a
platform that moves in substantially vertical direction and
functions as an elevator. The platform moves down to allow the next
mail piece to rest on top of the previous mail piece at
substantially the same position of the platform when it receives
the first mail piece in a stack.
[0009] It has been discovered that the elevator-type arrangement
can be organized to let the weight of the mail piece work against a
spring element so that a platform continuously moves down under the
weight of successive mail pieces. User adjustments can be
implemented to accommodate different mail piece sizes and
combinations. Alternatively, the platform can be moved down under
control of a motor and a sensing system and organized to facilitate
unloading requirements after which the platform would return to its
top position after the mail pieces have been unloaded.
[0010] It has also been discovered that productivity of the stacker
can be enhanced by eliminating the time required for the platform
to return to the top position by having a continuous elevator
arrangement where successive platforms, which may composed of
separate platform segments, can be on an endless belt arrangement.
The belts can be driven by motor or operated under the weight of
mail pieces being stacked on the platform. The bins may be
configured to hold a quantity of mail pieces suitable for an
operator to unload. The lowest bin continues to follow the belt
path and recycle to the top of the stacker. If all the bins are
full, a sensor can be provided to detect this condition and stop
the machine operation.
[0011] A mail piece stacker system embodying the present invention
includes a back wall and a side wall. A platform is mounted to be
adjacent to the back wall and the side wall. The platform is
moveable in a vertical direction and is adapted to support a stack
of mail pieces. A support spring is connected to the platform to
position the platform in a first vertical position when no mail
pieces are on the platform and to position the platform in a
different lower vertical position than the first vertical position
when the mail pieces are on the platform.
[0012] A method for stacking mail pieces embodying the present
invention includes the steps of moving mail pieces off a machine
exit seriatim onto a stacker platform. Adjusting the vertical level
of the stacker such that as mail pieces are moved onto the stacker
platform, the topmost mail piece surface remains at substantially
the height of the platform without any mail pieces on the
platform.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Reference is now made to the various figures, wherein like
reference numerals designate similar items in the various figures
and in which:
[0014] FIG. 1 is a perspective view of a mail piece stacker system
embodying the present invention;
[0015] FIGS. 2-5 are diagrammatic representations of the stacker
shown in FIG. 1 having different quantities of mail pieces on the
stacker platform; and,
[0016] FIG. 6 is an alternative embodiment of a mail piece stacker
system employing the present invention with stacker platforms
connected to an endless belt arrangement.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] Reference is now made to FIG. 1. Mail piece handling
equipment shown generally at 2 includes a machine with a mail piece
exit. The exit may be a mail piece conveyor 4 for conveying mail
pieces from the mail piece handling equipment 2. Mail pieces are
conveyed by the belts 6, 8, 10 and 12 toward a vertical stacker,
generally shown at 14. The vertical stacker 14 includes a base 16
which is physically connected by brackets 18 and 20 to the mail
piece handling equipment 2. This establishes a specific spatial
relation between the stacker 14 and the mail piece handling
equipment 2.
[0018] The stacker 14 includes a platform 22 for receiving mail
pieces exiting the mail piece handling equipment 2 and conveyed by
the conveyor 4 to the stacker 14. A stack of envelopes 24 is shown
neatly stacked on the platform 22. The mail pieces are transported
on conveyor belts 6, 8, 10 and 12. The platform 22 is connected to
a vertically moveable plate 26 having a handle 28 and forming part
of a back wall which includes the vertical plate 29 to which the
moveable plate 26 is attached. The plate 28 is at a right angle to
the side wall 30 of the stacker.
[0019] The platform 22 is positioned at an acute angle with respect
to the back wall of the stacker. Additionally, the platform 22 is
at an acute angle with respect to the side wall 30. In this manner,
where desired and where the acute angles are such to make the slope
of the platform sufficient, when a mail piece hits the back wall
moveable plate 26 and settles onto the stack 24, the mail piece
will tend to slide toward the side wall 30 and become registered in
the stack. The side wall 30 of the stacker is perpendicular to the
back wall; however, other angles may be employed. The platform 22
is oriented so that it is at a compound angle. The platform is
oriented at an acute angle with respect to the back wall and plate
22 and also at an acute angle with respect to the side wall 30.
Mail pieces which do not fly far enough to strike the back wall
plate 26 and land on the stack tend to slide toward the back wall
plate 26 and also toward the side wall 30, where they are
registered in the stack. When exiting the mail piece handling
equipment conveyor 4, the lead edge of the mail piece will hit the
back wall plate 26 and then settle onto the stack 24. Since the
stack 24 is angled due to the platform orientation, the mail piece
will tend to slide against the side wall 30 to become fully
registered.
[0020] A spring 31, shown diagrammatically in FIGS. 2-5 is
connected to the platform 22. When no mail pieces are stacked on
the platform 22, the platform 22 will assume a vertical position
substantially at the position of mail piece 24d. As mail pieces
move off the conveyor they become airborne and travel toward the
back wall. The mail piece will strike the back wall plate 26 and
settle onto the stack. Guide bars or strips 32 and 34 help guide
the portion of the mail piece trailing the lead edge of the mail
piece. The angled orientation of the platform 22, and also mail
pieces in the stack of mail pieces 24, facilitates the settling of
the mail piece onto the stack. The spring 31 is not shown in FIG.
1. The spring 31 is directly under and hidden from view in FIG. 1
by the platform 22. Spring 31 may be a compression type spring
connected to base 16 as shown in FIGS. 2-5.
[0021] A slot 36 is provided in the base 16. This enables the
stacker mechanism to be moved toward and away from the end of the
mail piece handling equipment conveyor 4 and the guide bars or
strips 32 and 34. This enables the stacker to accommodate different
width mail pieces. To facilitate unloading of the stacker, an
operator may lift the stack of mail pieces 24 by the handle 28.
This will raise the plate 26 and the attached platform 22 to a
comfortable height for unloading. A locking mechanism 38 (shown in
FIGS. 2-5) when engaged as shown in FIG. 5, locks the platform 22
in a position for unloading the stack of mail pieces 24.
[0022] The neatness of the stack of mail pieces is directly related
to how far the mail piece has to travel through the air or land on
a stack. With the present arrangement, as shown in the various
figures, by having a small drop, for example, a 3-4 inch drop,
there is a good likelihood of mail pieces stacking flat on the bin
platform and with the next mail piece landing directly on top of
the previous mail piece in a way that the mail piece stack is neat.
The further that the landing point, the platform or the bin floor
is from the place where the mail piece took off, the more likely
that the mail piece will flip or have erratic movement while
traveling through the air. Since the mail piece is aerodynamic and
since it does have a rotational characteristic as it leaves the
exit of the mail handling equipment, the further the distance the
mail piece moves through the air from the leap or exit point, the
more likely the mail piece is to flip or travel erratically and
then not end up being neatly stacked on the platform. By always
maintaining a platform catch point that is relatively close to the
mail handling equipment exit point, the greater the likelihood of
making a neat, organized mail piece stack.
[0023] As is illustrated in FIGS. 2-4, the stacker platform
functions similar to an elevator. The platform 22, under the action
of spring 31, starts with the platform 22 at a top position. As the
mail pieces stack on top of the platform 22, by virtue of the
weight of the stack 24, the spring 31 allows the platform 22 to
move down under the weight of the growing mail piece stack but
still presents a good landing point, on the top of the topmost mail
piece, for the next exiting mail piece to make a neat, flat
landing. This is because the topmost mail piece on the platform 22
is substantially at the position where the platform 22 was located
without any mail pieces stacked thereon.
[0024] Different mail pieces may have different weights, depending
on how many inserts are in the mail piece. However, the more
inserts in an envelope or mail piece, the thicker the envelope or
mail piece and thus the vertical position of the topmost mail
piece, which is the landing point for the next mail piece, remains
approximately constant for a given size envelope, regardless of the
number of inserts where an appropriate spring is employed. One
variable that makes the mail piece different in weight is generally
the width and length of the mail piece. However, many mail pieces
are of similar length. The mail piece widths often fall into two
major categories for many mail creation machines. One is the number
10 envelope, about 31/2 to 4 inches wide and about 9 inches long,
the other is the C5 envelope, which is about 6 inches wide and 9
inches long. The spring 31 can be tuned to accommodate these
different width mail pieces by either changing the spring
arrangement for the different width mail pieces (adding, removing
or substituting different springs or providing an adjustment
mechanism) or selecting a spring 31 that is an accommodation for
the different width mail pieces, such as No. 10 and/or C5
envelopes. The selection of a spring to accommodate the two width
mail pieces or multiple width mail pieces is a trade-off between
the settling of the platform 22 and the effort to change or tune
the spring. However, a spring can be selected that satisfactorily
accommodates multiple-sized mail pieces. Since the small size
envelopes are less aerodynamically stable than larger size
envelopes, by primarily accommodating the requirements of a No. 10
envelope, for example, a selection will be made that may still be
satisfactory for a C5 size envelope.
[0025] As noted above, a mail piece that is thicker with more
inserts pushes down more on the platform than a thinner envelope
with fewer inserts. The landing point for the next mail piece mail,
however, remains about the same regardless of whether the thicker
or thinner mail piece is on the platform 22 providing the landing
surface. Accordingly, whether a single insert or eight inserts are
in an envelope, the landing point for the next mail piece remains
at substantially the same height. A single insert makes a thinner
mail piece, which weighs less, and does not depress the spring and
platform as much as a thicker mail piece. Accordingly, a thinner or
thicker mail piece has a change in platform height, where the
topmost mail piece on the platform still remains at substantially
the same height regardless of which mail piece is placed on the
platform. If the mail piece is a thicker packet, it weighs more and
pushes the stack down more, but still ends up with the same landing
point for the next mail piece. It should be recognized that
selection of the spring 31 and/or changing the spring or tuning the
spring for different sized envelopes and other variables is a
design choice, depending upon the particular requirements for the
stacker and the media being employed.
[0026] Other important parameters in addition to the spring
selection are the platform angle with respect to the back wall
plate 26 and with respect to the side wall 30 and the location of
the back wall with respect to the mail piece exit point of the mail
handling equipment. The guides 32 and 34 may be arranged to guide
mail pieces exiting the mail handling equipment onto the mail piece
stack 24. The guides 32 and 34 guide portions of an envelope
trailing the lead edge of an envelope as they move off the conveyor
and onto the mail piece stack 24.
[0027] In general operation, mail pieces exit the mail handling
equipment conveyor 4 and hit the back wall plate 26 and drop onto
the stack 24. As the mail piece exits the conveyor 4, the mail
piece starts to fall and the lead edge of the mail piece is angled
downwardly with respect to the trail edge of the mail piece. In one
configuration, the mail piece hits the back wall about an inch
above where it will settle onto the platform 22 or topmost mail
piece in the stack 24. The greater the settling distance, the more
variation that may occur in the mail piece stack. As the mail piece
exits the equipment and moves off the edge of the conveyor 4
support, it begins a rotational movement no matter how fast the
mail piece moves off the edge of the equipment. The lead edge of
the mail piece starts to drop once the center of gravity goes over
the end of the mail piece handling equipment conveyor. At this
point, the mail piece starts a rotational movement. The mail piece
tends to rotate down but hits the back wall plate 26 and lands on
the stack 24 before it rotates too far. Otherwise, the mail piece
may end up with the lead edge going straight into the edge of the
mail piece stack 24 and the mail piece, clearly, in such case will
not stack properly.
[0028] The further the mail piece has to travel to get onto the
stack 24, the more time exists when the rotational movement of the
mail piece will continue and further travel tends to create an
erratic stacking. By keeping the stacking platform 22 at a
substantially stable position with limited vertical stacking height
movement and also close to the mail piece exit point for all mail
pieces, the rotational effect and erratic travel is minimized.
Additionally, orienting the platform 22 at an angle with respect to
the back-wall plate 26 further minimizes the distance the trailing
edge of a mail piece has to fall to settle onto the stack. This
angle mimics the approach angle of an airborne mail piece and less
time is needed for the trailing edge of the mail piece to settle
onto the platform 22 or the topmost envelope in the stack 24. This
further tends to reduce variation in the stacking of the mail
pieces.
[0029] When the platform stack is full, the platform 22 can be
positioned to assist the operator in unloading the stacker 14. A
platform lock 40 is provided. The platform lock 40 may include a
sliding member 42 (shown in FIG. 5) which will engage the platform
22 to lock the platform into a position to facilitate operator
unloading of the stacker 14. The handle 28 may be used by the
operator to lift the platform and the stack of mail pieces and lock
the platform for unloading. The position for unloading may be an
upper position as shown in FIG. 5. However, the position to
facilitate unloading is a matter of design choice based on the
equipment involved and the stacking apparatus.
[0030] As illustrated in FIGS. 2-5, a series of mail pieces are
being conveyed by the conveyor 4 and are about to be exited from
the conveyor 4 past the guides onto the stacker platform. FIG. 3
illustrates the platform 22 with a stack of mail pieces 24. The
platform 22 is at a lower vertical position under the weight of the
mail piece stack 24 than the platform 22 as shown in FIG. 2 with no
mail pieces. However, the top surface of the topmost mail piece on
the stack 24 is at approximately the same position of the platform
22 illustrated in FIG. 2 without any mail pieces thereon. FIG. 3
additionally illustrates a mail piece as having just struck the
back wall 26 and preparing to drop onto the stack.
[0031] As shown in FIG. 4, the back wall of the stacker 14 has been
moved and is positioned further from the conveyor 4 to accommodate
larger sized mail pieces, which are being stacked on the platform
22. A mail piece is shown as having exited the conveyor 4 and
moving onto the stack of mail pieces 24 on the platform. The trail
edge of the mail piece is guided by the guide 32.
[0032] A full stack 24 of mail pieces on platform 22 is illustrated
in FIG. 5. The platform 22 has been moved to an unloading position.
The platform 22 is locked into a position for unloading by engaging
locking mechanism 40. The locking is by virtue of the platform lock
sliding member 42 being moved into engagement with the underside of
platform 22.
[0033] Reference is now made to FIG. 6. The mail piece stacker 44
is shown with mail pieces 46 stacked on the elevator platform 48.
The elevator platform is composed of two elevator platform segments
48a and 46b. As mail pieces exit a machine, the mail pieces drop
onto the topmost bin, here bin 50, which is formed by platform 48.
The mail piece drops on top of the topmost mail piece that
previously exited the machine and were placed in bin 50. This is
similar to the arrangement shown in FIGS. 1-5 where the distance
the mail pieces need to travel through the air to be placed onto
the stack is controlled to avoid large distances. The bins of the
stacker 44 may have a capacity of, for example, about between 10-15
mail pieces, depending upon the thicknesses of the various mail
pieces. However, the capacity of the particular bin is a matter of
design choice.
[0034] As a bin, such as bin 50, is full, the bin moves down and a
new bin moves into position above the previous bin to continue to
receive mail pieces from the machine. The new bin will be formed by
platform segments 52a and 52b. At any time, there could be a number
of bins, such as five or six bins, holding mail pieces. An operator
could remove mail from any of the bins, however, the mail removal
would normally be from the lowest configured bin when it is not
receiving mail pieces. If the lowest bin is full, before it is
rotated to begin upward travel, sensor 54 will detect this
condition and stop the stacker 44 and mailing machine
operation.
[0035] The bins of stacker 44 are constructed as platforms or
shelves, with the particular arrangement shown in FIG. 6 having two
platform segments, mounted to belts 56a and 56b and 58a and 58b to
form a platform to support both sides of the mail pieces. Various
types of belt arrangements and platforms and segmented platforms
may be employed. The belts 56a, 56b, 58a and 58b are driven by a
motor 60. The motor 60 only needs power to move the bins with mail
pieces in a downward direction and empty bins in an upward
direction. Accordingly, the motor 60 can be of a small size. As the
lowest bin is emptied, the lowest platform segments continue to
follow the belts and are recycled to the top of the stack 44.
[0036] The entire bin array can be configured to be the size to fit
into a mailing tray. This would enable placing the mail tray over
the bin array and tilting the stacker 44 to rotate around pivot 62
into the mail tray to allow the operator to move all the stacked
mail pieces into the mail tray. The arrangement shown in FIGS. 1-5
may also be configured to employ a pivot to enable tilting of the
stacker 14. The tilting of the stackers 14 or 44, as the case may
be, is such that the stacked output order of the mail pieces is
preserved in neat stacks when moved into a mail tray. In the case
of the arrangement shown in FIGS. 1-5, the pivot would be
configured to avoid conflict with the mail handling equipment 2.
This can be achieved, for example, by pivoting the stacker away
from the mail handling equipment 2 and then swiveling the stacker
to empty the mail piece stack into the mailing tray or by moving
the mail handling equipment 2.
[0037] It should be recognized that while the detailed description
show stackable mail piece envelopes, the invention is suitable for
use with other types of mail pieces which are stackable.
Accordingly, when used herein, the term mail piece is intended to
be a broad term. Other modifications can be employed in the system.
Various platform and segmented platform arrangements, various types
of belt or chain arrangements, various types of springs and spring
configurations, back and side wall configurations and various types
of locking mechanisms can all be employed with the system. Various
materials can be selected for the back wall and for the guides to
dampen the effect of a mail piece strike and/or to facilitate mail
piece sliding. Moreover, various configurations for the stacker
back wall can also be implemented. For example, the back wall can
have the plate 26 recessed into the plate 29 to form a continuous
single surface as opposed to being mounted on the plate 29.
[0038] While the present invention has been described in connection
with what is presently considered the most practical and preferred
embodiments, it is to be understood that the invention is not
limited to the disclosed embodiment but, on the contrary, is
intended to cover various modifications and equivalent arrangements
included within the spirit and scope of the appended claims.
* * * * *