U.S. patent application number 10/081277 was filed with the patent office on 2002-10-03 for stacker.
Invention is credited to Ancliffe, Dan, Gasser, Thomas, Heeney, Mitch.
Application Number | 20020140162 10/081277 |
Document ID | / |
Family ID | 27574585 |
Filed Date | 2002-10-03 |
United States Patent
Application |
20020140162 |
Kind Code |
A1 |
Gasser, Thomas ; et
al. |
October 3, 2002 |
Stacker
Abstract
An apparatus for stacking a stream of moving sheet-like material
such as, for example, mailpieces is described. The apparatus
comprises a first moving belt positioned at a first level, the
first belt adapted to receive the sheets lying in a first
orientation and position the sheets downstream of the first belt; a
second moving belt positioned at a level lower than the first belt
and positioned whereby the sheets travel from an end position of
the first belt down a step to the second belt; a first sensor
positioned to sense break member in relation to the total thickness
of the sheets on the first belt thereby causing an incremental
movement of the first belt; a second sensor positioned in
contiguous relation to the step and adapted to sense the sheet-like
material as the sheets drop down the step to a second orientation
thereby incrementally moving the sheet-like material according to
the increased number of sheets on the second belt as they are
stacked thereon in the second orientation; and a movable back stop
member adapted to be locked onto the second belt, and further
adapted to help support and stack the sheets in the second
orientation, the stop member moving with the movement of the second
belt.
Inventors: |
Gasser, Thomas; (Bern,
CH) ; Ancliffe, Dan; (Datchet, GB) ; Heeney,
Mitch; (Datchet, GB) |
Correspondence
Address: |
PERMAN & GREEN
425 POST ROAD
FAIRFIELD
CT
06430
US
|
Family ID: |
27574585 |
Appl. No.: |
10/081277 |
Filed: |
February 21, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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60270796 |
Feb 23, 2001 |
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60277806 |
Mar 22, 2001 |
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60277841 |
Mar 22, 2001 |
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60277873 |
Mar 22, 2001 |
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60277931 |
Mar 22, 2001 |
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60277946 |
Mar 22, 2001 |
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60338892 |
Nov 5, 2001 |
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Current U.S.
Class: |
271/213 |
Current CPC
Class: |
G07B 2017/00427
20130101; B65H 2301/321 20130101; G07B 2017/00516 20130101; B65H
2511/51 20130101; B65H 5/00 20130101; B65H 2301/4214 20130101; B65H
2511/13 20130101; B65H 2701/1916 20130101; G07B 2017/00048
20130101; G07B 2017/00491 20130101; B65H 2555/13 20130101; B65H
3/042 20130101; B65H 31/06 20130101; B65H 2511/13 20130101; G07B
17/00467 20130101; G07B 2017/00137 20130101; G07B 17/00193
20130101; G07B 2017/00056 20130101; G07B 2017/00677 20130101; B65H
2220/01 20130101; B65H 2220/01 20130101; B65H 2220/11 20130101;
B65H 2220/02 20130101; B65H 29/18 20130101; B65H 2301/42144
20130101; G07B 2017/00935 20130101; B65H 2511/51 20130101; G07B
17/00024 20130101; B65H 2513/40 20130101; G07B 2017/00241 20130101;
G07B 2017/00177 20130101; G07B 2017/0029 20130101; G07B 2017/00258
20130101; B65H 2405/35 20130101; G06K 15/102 20130101; G07B
2017/00282 20130101; G07B 2017/00145 20130101; G07B 2017/00322
20130101; B65H 2513/40 20130101; B65H 2601/321 20130101; B41J
2/16547 20130101; B41J 2/1752 20130101; B65H 1/08 20130101 |
Class at
Publication: |
271/213 |
International
Class: |
B65H 031/04 |
Claims
What is claimed is:
1. An apparatus for stacking a stream of moving sheet-like material
comprising: a first moving belt positioned at a first level, the
first belt adapted to receive the sheet-like material lying in a
first orientation and position the sheet-like material downstream
of the first belt in an overlapped condition; a second moving belt
positioned at a level lower than the first belt and positioned
whereby the sheet-like material travels from an end position of the
first belt down a step to the second belt; a first sensor
positioned to sense break members in relation to the total
thickness of the sheets on the first belt thereby causing an
increased incremental movement of the first belt; a second sensor
positioned in contiguous relation to the step and adapted to sense
the sheet-like material as sheets drop down the step to a second
orientation thereby incrementally moving the sheet-like material
according to the increasing number of sheets on the second belt as
they are stacked thereon in the second orientation; and a movable
back stop member adapted to be secured to the second belt, and
further adapted to help support and stack the sheets in the second
orientation, the stop member moving with the movement of the second
belt.
2. A stacking apparatus according to claim 1 wherein said first
belt is driven by a DC motor.
3. A stacking apparatus according to claim 1 wherein said second
belt is driven by a stepper motor.
4. A stacking apparatus according to claim 1 wherein said
sheet-like material are mailpieces.
5. A stacking apparatus according to claim 4 wherein said
mailpieces are envelopes.
6. A stacking apparatus according to claim 1 wherein said first
orientation is substantially horizontal.
7. A stacking apparatus according to claim 1 wherein said second
orientation is substantially vertical.
8. A stacking apparatus according to claim 1 wherein said sheets
are dropped onto said second belt in a substantially vertical
position.
9. A stacking apparatus according to claim 1 including means for
repositioning said sheets from a first orientation to a second
orientation, the repositioning means located contiguous to said
step.
10. A stacking apparatus according to claim 1 further comprising a
second sensor adapted to detect each time a sheet is positioned on
said first belt and cause said first belt to advance each time a
sheet arrives on said first belt.
11. A stacking apparatus according to claim 10 wherein said first
belt advances a distance directly dependent on the length and
thickness of said sheet.
12. A stacking apparatus according to claim 1 wherein stacked
sheets positioned in said second orientation are strapped at said
step between said first and said second belts and said back stop
member.
13. A stacking apparatus according to claim 1 further comprising a
plurality of third sensors positioned along said second belt, the
third sensor adapted to control the movement of said second belt in
relation to the position of said back stop member.
14. A stacking apparatus according to claim 4 wherein said stacking
apparatus is one module of a modular mailing system.
15. A stacking apparatus according to claim 1 wherein the stacking
apparatus is adapted to be used in conjunction with a mailing
machine.
16. A stacking apparatus according to claim 15 wherein a main
incremental movement signal for the first belt comes from the
upstream feeder module in the mailing machine.
17. A stacking apparatus according to claim 1 wherein said
sheet-like material is fed to said first moving belt from a
position higher than said first belt.
18. A stacking apparatus according to claim 1 wherein there is
positioned a braking member in contiguous relation to the sheet
material positioned on said first belt, the braking member adapted
to stop the movement of the sheet material and thereby position the
sheets in an overlapped arrangement on said first belt.
19. A stacking apparatus according to claim 18 wherein said braking
member includes a switching device adapted to detect the thickness
of said sheet.
20. A stacking apparatus according to claim 19 wherein when said
thickness is greater than a certain amount, said switching device
sends a signal to said first belt causing said belt to speed up and
thereby help remove thick envelopes from the area of the brake.
21. An apparatus for stacking a stream of moving mailpieces, the
apparatus adapted to be used in conjunction with a mailing system
as the mailpieces are ejected seriatim from the mailing system
comprising: a first moving belt positioned at a first level, the
first belt adapted to receive mailpieces lying in a first
orientation and position the mailpieces downstream of the first
belt; a second moving belt positioned at a level lower than the
first belt and positioned whereby the mail travels from an end
position of the first belt down at step to the second belt; a first
sensor positioned to sense break members in relation to the total
thickness of the mailpieces on the first belt thereby causing an
incremental movement of the first belt; a second sensor positioned
in contiguous relation to the step and adapted to sense the
mailpieces as they drop down the step to a second orientation
thereby incrementally moving the mailpieces according to the
increasing number of mailpieces on the second belt as the
mailpieces are stacked thereon in the second orientation; and a
movable back stop member adapted to be locked onto the second belt,
and further adapted to help support and stack the mailpieces in the
second orientation, the stop member moving with the moving of the
second belt.
22. A stacking apparatus according to claim 21 wherein said
mailpieces are envelopes.
23. A stacking apparatus according to claim 21 wherein said first
orientation is substantially horizontal.
24. A stacking apparatus according to claim 21 wherein said second
orientation is substantially vertical.
25. A method for stacking a stream of mailpieces within a mailing
machine comprising: positioning in a first orientation a plurality
of mailpieces in an overlapped condition on a first moving belt;
positioning on a second moving belt in a second orientation the
plurality of mailpieces from the first moving belt, the second belt
being positioned at a lower level than the first belt; stacking the
mailpieces in the second orientation on the second belt while
supporting the stack of mailpieces on the second belt; and
controlling the movement of the second belt in relation to the
thickness of the stack of mailpieces on the second belt.
26. A method according to claim 25 wherein said mailpieces are
envelopes.
27. A method according to claim 25 wherein said first orientation
is a substantially horizontal orientation.
28. A method according to claim 25 wherein said second orientation
is a substantially vertical orientation.
29. A method according to claim 25 wherein the controlling of said
movement of said second belt in relation to the thickness of said
stack of mailpieces on said second belt is achieved by positioning
a plurality of sensors along said second belt the sensors adapted
to sense the thickness of said stack.
30. A method according to claim 29 wherein said sensors are optical
sensors.
31. A modular mailing system including a module for stacking a
stream of moving mailpieces, the stacking module comprising: a
first moving belt positioned at a first level, the first belt
adapted to receive moving mailpieces lying in a first orientation
and position the mailpieces downstream in the mailing system in an
overlapped condition, the belt moving in a response to a signal
from a feeding module positioned upstream in the modular mailing
system; a second moving belt positioned at a level lower than the
first belt and positioned whereby the mailpieces travel from an end
position of the first belt down a step to the second belt; a first
sensor positioned to sense brake members in relation to the total
thickness of the mailpieces on the first belt thereby causing an
increased incremental movement of the first belt; a second sensor
positioned in contiguous relation to the step and adapted to sense
the mailpieces as they drop down the step to a second orientation
thereby incrementally moving the mailpieces according to the
increasing number of mailpieces on the second belt as they are
stacked thereon in the second orientation; and a movable back stop
member adapted to be secured to the second belt, and further
adapted to help support and stack the mailpieces vertically, the
stop member moving with the movement of the second belt.
32. A modular mailing system according to claim 31 wherein said
first orientation is substantially horizontal.
33. A modular mailing system according to claim 31 wherein said
second orientation is substantially vertical.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority of the following U.S.
provisional patent applications: serial no. 60/270,796 filed on
Feb. 23, 2001, serial no. 60/277,806 filed on Mar. 22, 2001, serial
no. 60/277,841 filed on Mar. 22, 2001, serial no. 60/277,873 filed
on Mar. 22, 2001, serial no. 60/277,931 filed on Mar. 22, 2001,
serial no. 60/277,946 filed on Mar. 22, 2001 and serial no.
60/338,892 filed Nov. 5, 2001.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to an apparatus that is used for
stacking sheets-like material, and more particularly, to an
apparatus having particular use for stacking sheet-like material
such as mailpieces e.g., envelopes, which apparatus can be used
along with a postage meter (franking machine) in a mailing system
for stacking the envelopes processed through the postage meter.
[0004] 2. Description of Prior Developments
[0005] Sheet stacking machines, such as mail stacking machines,
have long been well known, and have been used quite successfully in
conjunction with mailing machines or other mail processing or
handling machines, such as mail sorting machines, stamp
cancellation machines, mail counting machines, inserting machines
and envelope printing machines. Typically, these sheet stacking
machines include an elongated frame which defines a feed path along
which mail pieces are fed toward a stacking location, the feed path
generally being disposed at a lower level than the mail piece
output location of the mailing machine or other mail processing or
handling machine, so that the ejected mail pieces fall upon an
elongated conveyor belt mounted on the frame. This conveyor moves
the mail pieces along a feed path to a stacking location, at the
end of which there is an upwardly angled wall which forms a ramp
against which the mail pieces are stacked by the conveyor belt. A
relatively large pressure wheel is pivotally mounted over the
conveyor belt at a point along the feed path which permits mail
pieces ejected from a mailing machine or mail processing or
handling machine to fall on the conveyor belt before passing under
the pressure wheel, which rests on mail pieces with sufficient
pressure to cause them to maintain effective feeding contact with
the conveyor belt.
[0006] One problem with many known stacking machines is that they
are generally incapable of producing a neat, even stack of mail
pieces since the mailpieces do not fall on the conveyor belt in
precisely aligned overlapping relationship, thereby resulting in a
stack in which the mailpieces lie in slightly staggered
relationship. This makes it difficult to handle a full size stack
when it must be removed from the stacking machine.
[0007] Still another problem generally encountered with many
stacking machines used with mail processing equipment is that they
do not stack thick mail pieces as effectively as they stack thin
mail pieces because the greater stiffness of thick mail pieces
makes it harder to urge these mail pieces under the pressure wheel
and to push them up a ramp.
[0008] Thus, in the mail processing business and with regard to the
technology of stacking sheet like material, there is a need for a
reliable stacking apparatus that will insure a proper stacking of
sheet materials, produce a neat and orderly stack of sheets, and
not be materially affected by variations in the thickness of the
sheets.
[0009] There is also a need for a reliable stacking apparatus in
which the length of the capacity of the stacker has been increased
while decreasing the conveyor belt length in a horizontal
plane.
SUMMARY OF THE INVENTION
[0010] The features and advantages of the present invention which
overcame the disadvantages of prior art structures are achieved by
an apparatus for stacking a stream of moving sheet-like material
comprising: a first moving belt positioned at a first level, the
first belt adapted to receive sheet material lying in a first
orientation and position the sheets downstream of the first belt in
an overlapped condition; a second moving belt positioned at a level
lower than the first belt and positioned whereby the sheets travel
from an end position of the first belt down a step to the second
belt; a first sensor positioned to sense break members in relation
to the total thickness of the sheets on the first belt thereby
causing an incremental movement of the first belt; a second sensor
positioned in contiguous relation to the step and adapted to sense
the sheet-like material as the sheets drop down the step to a
second orientation thereby incrementally moving the sheet-like
material according to the increasing number of sheets on the second
belt as they are stacked thereon in the second orientation; and a
movable back stop member adapted to be secured to the second belt,
and further adapted to help support and stack the sheets in the
second orientation, the stop member moving with the movement of the
second belt.
[0011] Another embodiment of the present invention relates to an
apparatus for stacking a stream of moving mailpieces, the apparatus
being adapted to be used in conjunction with a mailing system as
the mailpieces are ejected seriatim from the mailing system. The
stacking apparatus includes a first moving belt positioned at a
first level, the first belt adapted to receive mailpieces lying in
a first orientation and position the mailpieces downstream of the
first belt; a second moving belt positioned at a level lower than
the first belt and positioned whereby the mail travels from an end
position of the first belt down a step to the second belt; a first
sensor positioned to sense break members in relation to the total
thickness of the mailpieces on the first belt thereby causing an
incremental movement of the first relation belt; a second sensor
positioned in contiguous relation to the step and adapted to sense
the mailpieces as the mailpieces drop down the step to a second
orientation thereby incrementally moving the mailpieces according
to the increasing number of mailpieces on the second belt as the
mailpieces are stacked thereon in the second orientation; and a
movable back stop member adapted to be secured to the second belt
and further adapted to help support and stack the mailpieces in the
second orientation, the stop member moving with the movement of the
second belt.
[0012] Still a further embodiment of the present invention relates
to a method for stacking a stream of mailpieces within a mailing
machine comprising the steps of positioning in a first orientation
a plurality of mailpieces in an overlapped condition on a first
moving belt; positioning on a second moving belt in a second
orientation a plurality of mailpieces from the first moving belt,
the second belt being positioned at a lower level than the first
belt; stacking the mailpieces in the second orientation on the
second belt while supporting the stack of mailpieces on the second
belt in the second orientation; and controlling the movement of the
second belt in relation to the thickness of the stack of mailpieces
on the second belt.
[0013] Still a further embodiment of the present invention relates
to a modular mailing system including a module for stacking a
stream of moving mailpieces. The stacking module includes the
above-described features for a stacking apparatus as described
hereinabove.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The foregoing aspects and other features of the present
invention are explained in the following description, taken in
connection with the accompanying drawings, wherein:
[0015] FIG. 1 is a side plan view of a stacking apparatus in
accordance with the features of the present invention along with an
apparatus which feeds sheet-like material to the stacker;
[0016] FIG. 2 is a side plan view of a portion of the stacking
apparatus in accordance with the features of the present invention
particularly illustrating the overlapping feeding arrangement of
the sheets-like material;
[0017] FIG. 3 is a side plan view of a portion of the stacker
apparatus in accordance with the features of the present invention
particularly illustrating how the sheet's are supported by a
support member on a second belt and how the orientation of the
sheet members change from a first (primarily horizontal)
orientation to a second (primarily vertical) orientation; and
[0018] FIG. 4 is a side plan view of the entire stacker apparatus
in accordance with the features of the invention illustrating the
positioning of the various motors and sensors used in conjunction
with the stacking apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(s)
[0019] The stacker apparatus in accordance with the features of the
present invention can be used for stacking any type of sheets-like
material, such as for example, sheets of paper, sheets of thin
plastic etc. which are being fed through some sort of sheet
conveying system. For purposes of being able to explain the details
of the present invention in the form of an example, this
application shall describe a stacker apparatus that is used for
stacking paper sheets in the form of mailpieces (e.g. envelopes)
which are being fed within a mailing machine system. As shown in
FIG. 1, the stacking apparatus 10 in accordance with the present
invention is comprised of two different levels of belt-type
conveyors, i.e. a first belt conveyor 11 called the "landing belt"
and a second belt type conveyor 12 called the "stacking belt", the
second belt or stacking belt being positioned lower than the first
belt conveyor 11. As shown, the end portion 13 of the first belt
conveyor is in contiguous relation and slightly overlaps the
beginning portion 14 of the second or "landing" belt 12.
[0020] In accordance with the example that is being presented
herein, mailpieces (e.g. envelopes) being fed within mailing system
15 are fed seriatim to first belt member 11 in a first orientation,
or basically in a horizontal position. As illustrated in FIG. 2,
envelopes 16 are fed seriatim from a mailing machine system 15 (see
FIG. 1), and are positioned on belt 11 in an overlapped arrangement
due to the interaction of break member 17 on the horizontally
orientated envelopes.
[0021] The envelopes 16 are received on belt 11 from a mailing
machine system 15. Mailing machine system 15 could be, for example,
a modular mailing system, and the envelopes could be directly
received on belt 11 from a mailing machine module where the
envelope has been processed by a moistener and sealed, and is now
ready to be stacked for further processing. The envelopes are
received from mailing machine system 15 and placed in an overlap
position on the first conveyor belt 11 (see FIGS. 1 and 2). The
mailing machine system 15 feeds the envelopes 16 out onto the belt
conveyor machine 11 at a relatively fast pace in sequential, serial
fashion, i.e. in seriatim so that the envelopes are oriented in a
substantially horizontal position on belt 11. Mailing machine
system 15 does not feed envelopes 16 in an overlapped condition but
this occurs due to break member 17 and the speed of belt 11. The
primary purpose of the first belt conveyor 11 and brake member 17
is to slow down the speed of the traveling envelopes 16 and place
the envelopes in an overlapped arrangement, as clearly illustrated
in FIGS. 1-3. First belt conveyor 11 is positioned below the
conveyor (not shown) within mailing machine system 15. Brake member
17 is positioned over first conveyor belt 11 as clearly shown in
FIG. 2. Brake member 17 is preferably formed of a plurality of
stiff spring loaded finger members with a roller at the end laying
on belt 11 (e.g. plastic fingers) that function to stop the
movement of envelopes 16 and position the envelopes so that they
lie in an overlapped arrangement on belt 11 as shown in FIG. 2.
First conveyor belt 11 moves in an incremental fashion to
accomplish the overlapped arrangement of the envelopes on belt 11.
In operation, brake member 17 is first hit by the fast moving
envelope 16 as it exits the mailing machine system 15 and the
leading edge of each envelope drops down on conveyor belt 11 in a
substantially horizontal position. A signal is sent from the
mailing machine system 15 (e.g. from a feeder module in a modular
mailing system) to the drive system for belt 11 as each envelope 16
is forwarded to belt 11. When the drive system for belt 11 receives
such a signal it moves one increment ahead. This type of
incremental movement by belt 11 produces the overlapped arrangement
for a series of envelopes 16. Brake member 17 is preferably made of
stiff plastic fingers with a roller on their end laying on belt 11
and is formed of, for example, three stiff plastic finger elements
in the same row. The end 18 of the brake member 17 have a roller to
them as illustrated in FIG. 2. The bottom portion of break member
17 is laying on the first belt conveyor 11. The brake member 17
also includes a limit switch as specifically illustrated in FIG. 4.
The function of the limit switch is to detect when the thickness of
the envelope is very large. When this occurs the limit switch sends
a signal to the first conveyor belt 11 to increase the speed of
belt 11 and get the thick envelopes out of the brake area quickly.
This is done to prevent the mailing machine system 15, which is in
the process of continuously feeding envelopes 16 onto first
conveyor 11, from being jammed up. The first conveyor belt 11
should always have the envelopes placed thereon in an overlapped
fashion prior to the envelopes being transferred to the second belt
12. By employing a limit switch as described above, the balancing
of the overlapped envelopes reverses a possible jam, and the
mailing system is operated on an ad-hoc basis.
[0022] The brake member 17 can be switched to a 90-degree
orientation assuming that the conveyor's orientation relative to
the mailing machine system is switched 90 degrees. The screws that
hold the brake in the frame must be undone and the brake physically
attached at a 90-degree orientation.
[0023] There is a control mechanism for the overall control of the
overlapped stack of envelopes being carried by the first conveyor
11 to a backstop support member 20 located on and secured to the
second conveyor belt 12 (see FIG. 3). As the stack of envelopes 16
against the backstop 20 gets thicker and smaller wheel 21 against
the stack of envelopes (see FIG. 4) moves clockwise, and
furthermore when the back stop 20 gets to a certain position,
signals are conveyed to the second conveyor belt 12 to move
incrementally. FIG. 4 also shows the location of various sensors
and motor control sensors that are used in the system. The larger
wheel 22 keeps track of very thick envelopes being carried by the
first conveyor belt 11 and with its sensor can instruct the second
conveyor belt 12 to move incrementally for the thicker
envelopes.
[0024] It is preferable to have a drop off between the first and
second conveyors 11 and 12. The reason for this is that if there is
no such drop off, and the back plate 20 on the second conveyor belt
12 is at a steep angle, the envelopes 16 could fall over onto the
second conveyor 12. The bottom portion 16A of each of the envelopes
16 rest against the backstop 20 and slip down into the space 25
provided by the envelope drop point. The envelopes resting against
back plate 20 on a second conveyor belt 12 are now in a
substantially vertical position. A series of sensors 30, 31 and 32
are positioned along the second conveyor belt 12 for the purpose of
measuring the amount of capacity that is being used on conveyor
belt 12 to support envelopes in a substantially vertical position.
When, for example envelopes 16 have started to be dropped onto
second conveyor 12, a trip sensor 33 which is built in above the
step between belts 11 and 12, detects envelopes as they drop.
Sensors 33 causes stepper motor 34 to turn on and incrementally
move the stack of now vertically positioned envelopes 16 away from
the step area until the sensor is not longer triggered and the
movement of belt 12 stops. Movement of belt 12 causes movement of
back plate 20 since back plate 20 is secured to belt 12. There is
approximately a 50 m.m step down distance from the first conveyor
belt 11 to the second conveyor belt 12. The step (drop) from the
first conveyor 11 to the second conveyor 12 can be as small as
possible so long as the bottom portions 16A of envelope 16 keep
together against back stop 20. As illustrated in FIG. 4, envelopes
16 enter the mail stream from a mailing system designated by arrow
29. The envelopes could be directly from a postage meter, a feeding
device or an addressing system. The envelops are positioned
substantially horizontally and move long until they turn towards a
substantially vertical position and drop on to the second conveyor
belt 12.
[0025] Conveyor belt 11 advances each time an envelope 16 arrives
from the mail stream. The distance of a the advance depends upon
the envelope length, (the envelope length information generally
comes from a Feeder device) and the thickness of the arriving
envelope.
[0026] Although back plate 20 is in a secure locked position onto
conveyor belt 12, it has the option of being able to be moved by
hand to reset the position of the back plate. In the structure
shown in FIG. 4 there is illustrated the use of three sensors along
the second conveyor belt 12, i.e. a 0% sensor (indication that no
envelopes are being supported on conveyor belt 12); a 75% full
sensor (indicating that 75% of conveyor belt is being used, i.e.
stacked with envelopes); and a 95% full sensor (indicating that 95%
of conveyor belt 12 is being used i.e. stacked with envelopes).
[0027] When the back plate 20 reaches the 75% sensor 31, the
postage meter positioned in the mailing machine will given an
acoustic signal. On reaching the 95% full sensor 32, the entire
postage meter stops working.
[0028] The 75% and 95% full sensors (31 and 32) are movable
according to user needs. In addition, in accordance with the
features of the present invention, the sensors employed in the
system described herein can be optical, mechanical or electrical
sensors.
[0029] It should be understood that the foregoing description is
only illustrative of the invention. Various alternatives and
modifications can be devised by those skilled in the art without
departing from the invention. Accordingly, the present invention is
intended to embrace all such alternatives, modifications and
variances which fall within the scope of the appended claims.
* * * * *