Note: Descriptions are shown in the official language in which they were submitted.
2096701
~N9009
SYST~M FOR AUTCMATIC~Y ST~GING } USBD
I~ C~hN~lON ~IT~ A L~ ~K SOk.ld~ ~C~T~E
FIELD OP THE lNvKN-llON
The invention relates to letter sorting systems, such
as systems employed by the United States Postal~Servic~e. The
inven~ion al90 relates to automatic storage and retrieval
sy~tems.
~AC~GROUND OF THE r~v~NllON
The United States Postal Service employs many types of
letter 90rting machine~. Some examples are bar code sorters,
optical character readers, multiple position letter sorters and
delivery bar code 90rters. Such letter sorting ma~hine~ are well
known to those skilled in the art, and the~e machine~ will
therefore not be described in greater detail.
The operation of these machines is currently quite
labor intensive. Letters are generally conveyed to and from
letter sorting machines in trays which are in turn conveyed in
relatively large carts that are moved by hand. This requires a
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significant amount of labor, and the carts take up a significant
amount of floor space. Two-pass delivery bar code sorters also
require staging or ~toring of letters between passes. Such
staging is currently done with the same trays and carts,
resulting in the same disadvantages.
Many letter sorting machines are modular, i.e., their
capacity can be increased or decreased by adding or removing
modular units.
SUMM~RY OF THE INVENTION
The invention provides a modular system for
automatically staging or storing trays of letters for input to a
letter sorting machine and for automatically staging letters
dispensed by a letter sorting machine. The invention also
provides an improved automatic storage and retrieval machine.
The system can be used in connection with any type of
letter sorting machine. When used in connection with a two-pass
delivery bar code sorter, the system also automatically presents
letter trays in proper order for the second pass, automatically
stages letters from the letter sorting machine after the second
pass, and automatically presents letter trays in proper order for
conveyance after the second pass.
The system is modular, so it can be tailored to a
letter sorting machine of virtually any ~ize. The modular nature
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of the system enables relatively quick installation of the system
in existing facilities. The system can be fit within various
types of building layouts and can be interfaced with various
delivery and take-away systems. The system can be located close
to a letter sorting machine so that relatively little labor is
required to move letters from the sorting machine to the system.
The system takes advantage of available vertical air space and
requires a m; n;m~lm amount of floor space. The height of the
system can be varied to take advantage of existing overhead
clearance. The system provides faster and more accurate staging
than can be done manually. _ _
Overall, the system provides substantial floor space
savings, substantial capital cost savings, and substantial labor
savings.
Specifically, the system comprises, along with a letter
sorting machine, an automatic storage and retrieval system. The
automatic storage and retrieval system includes a staging or
storage rack and a storage and retrieval machine which is
positioned to receive letter trays from the sorting machine and
to present letter trays for input to the sorting machine and
which is operable to stage letter trays in and retrieve letter
trays from the staging rack. The staging rack is modular and
includes a number of discrete modules each providing several
levels and bays of staging locations, such that the number of
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staging locations can be varied by varying the number of module~.
The modules are arranged end-to-end, ~o that the length of the
system can be adapted to the length of the letter sorting
machine. The staging locations of the staging rack are by de~ign
provided by cantilevered shelves. Because the shelves are
cantilevered, there are no partitions between adjacent staging
locations. This affords a maximum number of staging locations in
a given space.
The storage racks used in connection with prior art
storage and retrieval machines must be specially designed to
accommodate a shuttle mechanism or extractor. For example, if
the rack includes shelves defining the storage locations, thoce
shelves mu~t be discontinuous or otherwise specially configured
to permit placement of the extractor plate beneath a stored
object. A further disadvantage associated with prior art storage
and retrieval machines is the need to lift objects on and off the
storage rack. This requires the mechanism for supporting the
extractor plate to be of a heavy, durable construction, and to be
carefully maintained. The extractor of the present invention
avoids the foregoing disadvantage~.
The storage and retrieval machine provided by the
invention includes a mast movable horizontally adjacent the
staging rack, a carriage movable vertically relative to the mast,
and an extractor movable relative to the carriage for placing
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letter trays in and extracting letter trays from the staging
rack. The carriage and extractor assembly differs from known
assemblies in that, among other things, it has been specifically
adapted for handling letter trays. Rather than extending below
and picking up the object to be moved (the letter tray), the
extractor of the present invention extends above a letter tray
and pulls or slides the letter tray onto the carriage. This
permits the extractor to be more lightly constructed and
supported than prior art extractors. The extractor includes two
hoop-like mechanisms that swing down and engage or capture the
letter tray, and the combination of the hoop-like mechanisms and
the location of the extractor immediately above the letter tray
substantially prevents letters from coming out of the letter tray
while the storage and retrieval machine is moving the letter
tray. Movement of the hoop-like mechanisms is actuated by one or
more motors.
More particularly, the extractor includes one or more
plate members that are supported for horizontal extension and
retraction relative to the carriage. The plate members include
an uppermost plate member that is stationary with respect to the
carriage, and one or more successively lower plate members that
are each preferably slideably supported with respect to the
preceding plate member. When extended, the plate members extend
outwardly in the same direction and in generally cantilevered
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relation to each other. The number of plate members used can be
varied to change the length of extension of the extractor. When
in the retracted condition, the plate members are aligned in
generally vertically stacked relation within the carriage so that
they do not interfere with movement of the carriage. Suitable
moving means, such as an electric motor on the carriage or on the
uppermost plate member, is provided to move the plate members
between extended and retracted positions.
When used in conjunction with a two-pass delivery bar
code sorter (DBCS), the system also comprises a sweep rack on
each side of the DBCS. Each sweep rack provides, for each output
stacker of the DBCS on the same side of the DBCS, a respective
letter tray staging position. The sweep racks are located such
that an operator (a sweep operator) can easily move or nsweepn
letters from an output stacker to the associated letter tray
supported by the sweep rack. The sweep racks are, like the
staging rack, modular. The staging rack and the storage and
retrieval machine are located on one side of the DBCS, and the
sweep rack on that side of the DBCS (the near-side sweep rack) is
located beneath the staging rack. By design, the modules of the
sweep rack are the same length as the modules of the staging
rack, and each staging rack module is mounted on top of a
respective sweep rack module.
2096701
The system also comprises an input tray transport
system or conveyor for transporting or conveying letter trays
from the opposite-side sweep rack to the storage and retrieval
machine. This tray transport system also conveys trays from the
near-side sweep rack to the storage and retrieval machine. The
tray transport system is by design horseshoe-shaped and runs
through the opposite-side sweep rack, around the end of the DBCS,
and through the near-side sweep rack. The tray transport system
terminates adjacent the station of the DBCS feed operator. The
tray transport system i9 located in the sweep racks such that a
sweep operator can easily place trays from either sweep rack onto
the tray transport system. The tray transport system is
accessible by the storage and retrieval machine at a point near
the downstream end of the tray transport system, i.e., at the end
of the near-side sweep rack. All letter trays from the opposite-
side sweep rack are conveyed to either the feed operator or the
storage and retrieval machine by the tray transport system.
The system also comprises, in the near-side sweep rack,
output belts or conveyors for carrying letter trays to the feed
operator. Each output belt is aligned with and located behind an
associated level of staging positions in the near-side sweep
rack, such that the sweep operator can push letter trays from any
one of the staging positions onto the associated output belt.
The downstream end of each output belt is located adjacent the
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feed operator station, and each output belt is accessible
adjacent its downstream end by the storage and retrieval machine.
The operation of the system with a two-pass DBCS will
be described only generally at this point. A more detailed
description follows.
Letter trays coming to the DBCS are placed on the
upstream end of the input tray transport system. Many of these
letter trays are staged by the storage and retrieval machine, and
the remainder of the letter trays are retrieved by the ~torage
and retrieval machine and placed on one of the output belts to be
delivered to the feed operator. After the trays on the input
tray transport system have been delivered to the feed operator,
the storage and retrieval machine delivers the trays in the
staging rack to the feed operator.
During and after first pass, the sweep operator places
letters from each output stacker into the associated letter tray
in the associated sweep rack. The letter tray carries a bar code
identifying the associated DBCS output stacker. Full letter
trays are placed on the input tray transport system for transport
to the storage and retrieval machine. When first pass has ended,
letter trays remaining on the opposite-side sweep rack are placed
on the input tray transport system for transport to the storage
and retrieval machine, and letter trays remaining in the near-
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side sweep rack are pushed onto the output belts for transport to
the feed operator.
As the system presents letter trays to the feed
operator for second pass, the system insures that all filled
trays that were placed on the input tray transport system are
presented to the feed operator in proper sequence. Operation
during second pass is similar to operation during first pass.
After second pass, letter trays are staged for subsequent
conveyance rather than for another pass through the DBCS.
Thus, the invention provides a letter sorting apparatus
including a letter sorting machine having means for receiving
letters to be sorted, means for sorting letters, and means for
dispensing sorted letters. The letter sorting apparatus also
includes means separate from the letter sorting machine for
automatically staging letters from the dispensing means.
The invention also provides a letter sorting apparatus
including a letter sorting machine having means for receiving
letters to be sorted, means for sorting letters, and means for
dispensing sorted letters. The letter sorting apparatus also
includes means separate from the letter sorting machine for
automatically staging letters for input to the receiving means.
The invention also provides a letter sorting apparatus
including a letter sorting machine that has means for receiving
letters to be sorted and means for sorting letters. The letter
g
209 67 0 1 ~RN~
sorting apparatus also includes an automatic storage and
retrieval system including means defining a plurality of storage
locations, and a storage and retrieval machine. The storage and
retrieval machine is positioned to receive letters from the
sorting means and to present letters for input to the receiving
means, and is operable to store letters in and retrieve letters
from the storage locations.
The invention also provides a letter sorting apparatus
including a letter sorting machine which has two sides and which
includes means for receiving letters to be sorted, means for
sorting letters, and means on both of the sides for dispensing
sorted letters. The letter sorting apparatus also includes an
automatic storage and retrieval system including means defining a
plurality of staging locations, and a storage and retrieval
machine operable to stage letters in and retrieve letters from
the staging locations. The letter sorting apparatus further
includes first staging means adjacent one of the sides of the
letter sorting machine for staging letters from the sorting
means, the staging means including means defining a plurality of
staging positions, means for transporting letters from the first
staging means to the storage and retrieval machine, the
transporting means including a transport system located adjacent
the staging positions such that an operator can push letter
receptacles from the staging positions onto the transport system,
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second staging means adjacent the other side of the letter
sorting machine for staging letters from the sorting means, and
means for transporting letters from the second staging means to
the storage and retrieval machine.
The invention also provides an automatic storage and
retrieval system including means defining a plurality of storage
locations, a storage and retrieval machine operable to store
objects in and retrieve objects from the storage locations,
storing means defining a plurality of storage positions, and
means for conveying objects from the storing means to the storage
and retrieval machine. The conveying means includes a conveyor
located adjacent the storage positions such that an operator can
push objects from the storage positions onto the conveyor.
The invention also provides an automatic storage and
retrieval system including storing means defining a plurality of
storage positions, means defining a plurality of storage
locations above the storage positions, a storage and retrieval
machine operable to store objects in and retrieve objects from
the storage locations, and means for conveying objects from the
storing means to the storage and retrieval machine.
The invention also provides an automatic storage and
retrieval system including one or more discrete modules each
defining a plurality of storage locations, such that the number
of storage locations can be varied by varying the number of the
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2096701
modules, and a storage and retrieval machine. The storage and
retrieval machine is operable to store objects in and retrieve
objects from the storage locations.
The invention also provides a method of handling
letters being sorted by a letter sorting machine. The method
includes the steps of providing an automatic storage and
retrieval system including means defining a plurality of staging
locations, and a storage and retrieval machine, transporting
letters from the sorting machine to the storage and retrieval
machine, and operating the storage and retrieval machine to stage
letters in and retrieve letters from the staging locations.
_
The invention also provides a method of handling
letters being sorted by a letter sorting machine. The method
includes the steps of providing an automatic storage and
retrieval system including means defining a plurality of staging
locations, and a storage and retrieval machine, transporting
letters to the storage and retrieval machine, and operating the
storage and retrieval machine to stage letters in and retrieve
letters from the staging locations and to stage letters for input
to the receiving means.
The invention also provides a letter sorting apparatus
including a letter sorting machine having means for receiving
letters to be sorted, means for sorting letters, and means for
dispensing sorted letters. The letter sorting apparatus also
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includes an automatic storage and retrieval system for
automatically staging letters from the dispensing means, the
system including a storage rack, the storage rack including a
shelf having a continuous upwardly facing surface defining a
plurality of storage locations, and a storage and retrieval
machine. The storage and retrieval machine is positioned to
receive letters from the dispensing means, and includes a base
adapted to move horizontally along a supporting surface and an
extendable and retractable shuttle mechanism supported by the
base for placing letters in and removing letters from the storage
locations.
The invention also provides a storage and retrieval
machine including a base adapted to move horizontally along a
supporting surface, a generally vertical mast supported by the
base, a carriage supported for generally vertical movement along
the mast, and an extendable and retractable shuttle or extractor
mechanism supported by the carriage. The extractor includes an
upper plate fixed against horizontal movement relative to the
carriage, an intermediate plate which is located below the upper
plate and which is supported by the upper plate for horizontal
movement relative thereto, and a lower plate which is located
below the intermediate plate and which is supported by the
intermediate plate for horizontal movement relative thereto. The
shuttle mechanism is operable between a retracted condition
2~96701
wherein the intermediate plate i9 located directly below the
upper plate and the lower plate is located directly below the
intermediate plate, and an extended condition wherein the
intermediate plate extends outwardly in one direction relative to
the upper plate and the lower plate extends outwardly in the one
direction relative to the intermediate plate.
The invention also provides a storage and retrieval
machine including a base moveable horizontally along a supporting
surface, a generally vertical mast supported by the base, a
carriage supported for generally vertical movement along the
mast, and shuttle means for sliding a load onto and off the
carriage without exerting an upward force on the load.
The invention also provides an automatic storage and
retrieval system including a storage rack having a shelf with a
continuous upwardly facing surface defining a plurality of
storage locations, and a storage and retrieval machine. The
storage and retrieval machine includes a base moveable
horizontally along a supporting surface, and an extendable and
retractable shuttle or extractor mechanism supported by the base
for placing objects in and removing objects from the storage
locations.
The invention also provides a storage and retrieval
machine including a base moveable horizontally along a supporting
surface, a generally vertical ma~t supported by the base, a
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2Q96701
carriage supported for generally vertical movement along the
mast, and an extendable and retractable shuttle or extractor
mechanism supported by the carriage. The extractor includes a
plate-like member movable horizontally relative to the carriage,
a first motor for moving the member relative to the carriage, a
second member movable relative to the plate-like member for
engaging an object to be moved by the extractor, and a second
motor for moving the second member relative to the plate-like
member.
The invention further provides a storage and retrieval
machine including a base moveable horizontally along a supporting
surface, a generally vertical mast supported by the base, a
carriage supported for generally vertical movement along the
mast, and an extendable and retractable shuttle or extractor
mechanism supported by the carriage. The extractor includes a
plate movable horizontally relative to the carriage, and means on
the plate for selectively engaging an object so that the object
moves horizontally with the plate, the means for selectively
engaging the object including a member movable relative to the
plate between an upper po~ition and a lower position.
Other features and advantages of the invention will
become apparent to those skilled in the art upon review of the
following detailed description, claims and drawings.
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2096701
DESCRIPTION OF THE DRAWINGS
Fig. 1 i~ a top plan view of a letter sorting apparatus
embodying the invention.
Fig. 2 is a view taken along line 2-2 in Fig. 1.
Fig. 3 i8 a view taken along line 3-3 in Fig. 1.
Fig. 4 is a view taken along line 4-4 in Fig. 1.
Fig. 5 is a partial perspective of the apparatus.
Fig. 6 is an enlarged view which is taken along line
6-6 in Fig. 2 and which shows the carriage and extractor assembly
with the extractor in a retracted position.
Fig. 7 is a left side elevational view of the carriage
and extractor assembly shown in Fig. 6.
Fig. 8 is a top plan view, partially broken away, of
the carriage and extractor assembly shown in Fig. 6.
Fig. 9 is a view taken along line 9-9 in Fig. 8.
Fig. 10 is a reduced top plan view of the carriage and
extractor assembly shown in Fig. 6 with the extractor extended.
Fig. 11 is a side elevational view of the carriage and
extractor assembly shown in Fig. 10 and with the extractor in an
extended position.
Fig. 12 is a top plan view of an alternative embodiment
of the invention which includes a bar code sorter rather than a
delivery bar code sorter.
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2096701 H~RN~
Fig. 13 i8 a top plan view of a second alternative
embodiment of the invention which includes an optical character
reader rather than a delivery bar code sorter.
Fig. 14 is a top plan view of a third alternative
embodiment of the invention which includes a one-sided delivery
bar code sorter rather than a two-sided delivery bar code sorter.
Fig. 15 is a view taken along line 15-15 in Fig. 1.
Fig. 16 is an enlarged side elevational view of the
storage and retrieval machine shown in Fig. 2.
Fig. 17 is an enlarged view of a portion of the storage
and retrieval machine shown in Fig. 16.
Fig. 18 is a left end view of the storage and retrieval
machine portion shown in Fig. 17.
Fig. 19 is a view taken along line 19-19 in Fig. 17.
Fig. 20 is a view taken along line 20-20 in Fig. 16.
Fig. 21 is a further enlarged view of a portion of the
storage and retrieval machine shown in Fig. 16, showing
attachment of the base of the machine to a drive belt.
Fig. 22 is a side elevational view of a carriage and
extractor assembly including an alternative extractor
construction shown with the extractor extended and the hoops
lowered.
Fig. 23 is a top plan view of the carriage and
extractor assembly shown in Fig. 22.
2096701 ,~",900
Fig. 24 is side elevational view of a portion of the
carriage and extractor assembly shown in Fig. 22 but with the
hoops raised.
Fig. 25 is a view similar to Fig. 24 showing the
opposite side of the extractor.
Fig. 26 is an end elevational view (from the left in
Fig. 22) of the extractor in the retracted condition.
Fig. 27 i8 a partial side elevational view similar to
Fig. 22 of a second alternative extractor construction shown with
the extractor extended and only one of the hoops lowered.
Before one embodiment of the invention is explained in
detail, it is to be understood that the invention is not limited
in its application to the details of the construction and the
arrangements of components set forth in the following description
or illustrated in the drawings. The invention is capable of
other embodiments and of being practiced or being carried out in
various ways. Also, it is to be understood that the phraseology
and terminology used herein is for the purpose of description and
should not be regarded as limiting.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A letter sorting apparatus 10 embodying the invention
is illustrated in Figs. 1-5. The apparatus 10 comprises a letter
sorting machine 14. While any suitable letter sorting machine
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can be used, the illustrated letter sorting machine is a delivery
bar code sorter (DBCS) that is utilized by the United States
Postal Service and that is manufactured by Electrocom Automation,
Inc. of Dallas, Texas. Such a DBCS is well known to those
skilled in the art and will be described only to the extent
necessary for a full understanding of the present invention.
Other types of letter sorting machines to which the invention is
applicable include, for example, bar code sorters, optical
character readers and multiple position letter æorting machines.
The DBCS 14 has opposite ends (left and right ends in
Fig. 1) and opposite sides (upper and lower or opposite and near
sides in Fig. 1). The DBCS 14 includes, at its left end, means
18 for receiving letters to be sorted. A feed operator puts
letters into the receiving means or input of the DBCS 14. The
DBCS 14 also includes means for sorting letters, and means on
both of the upper and lower sides for dispensing sorted letters.
The dispensing means includes three levels of output stackers 22
on both sides of the DBCS 14. A sweep operator on each side
removes sorted letters from the output stackers 22. The portion
of the DBCS 14 including the output stackers 22 is made of
modules 26. Each module 26 is approximately 110 inches long and
includes eight output stackers per level.
Letters are sorted to individual area routes by passing
the letters twice through the DBCS 14. In other words, letters
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are initially put into the receiving means 18, and the DBCS 14
reads the bar codes on the letters, partially sorts the letters,
and dispenses the letters to the output stackers 22. The letters
are then again put in the receiving means for a second pass
through the DBCS. Letters in the output stackers 22 must be
presented to the receiving means 18 in the proper order for the
second pass. After the second pass, the DBCS 14 dispenses to the
output stackers 22 letters sorted to the individual carrier
routes. Before and after sortation by the DBCS 14, letters are
staged and transported in conventional letter receptacles or
trays 46.
The apparatus 10 also comprises means adjacent the
opposite side of the DBCS 14 for storing or staging trays of
letters. While various suitable opposite-side staging mean~ can
be employed, in the illustrated embodiment, such means includes
(see Fig~. 1 and 4) a modular staging or storage or sweep rack 30
fixed to the floor or other supporting surface. As shown in
Fig. 4, the sweep rack defines three levels of staging or storage
positions 34, with each level being generally aligned with a
respective one of the levels of output stackers 22 on the
opposite side of the DBCS 14. Each level is defined by an
outwardly and upwardly sloped ~helf 38 and includes eight staging
po~itions 34, with each staging position 34 being generally
aligned with a respective one of the output stackers 22 of the
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2096701
DBCS 14. Each of the staging positions 34 is adapted to receive
a letter tray 46, so that a sweep operator can simply "sweep"
letters from an output stacker of the DBCS 14 to the letter tray
46 in the associated staging position. Each tray 46 has thereon
a bar code 47 (Fig. 5) identifying the associated output stacker
22. The sweep rack 30 is made of modules 48 (Fig. 1). By
design, each module 48 of the ~weep rack is approximately 110
inches long, like the modules 26 of the DBCS 14, and includes
eight staging positions 34 per level. Located on top of the
sweep rack 30 i8 a non-powered skate wheel conveyor 49 (Fig. 4),
the reason for which is explained below.
The apparatus 10 also comprises means adjacent the near
side of the DBCS 14 for storing or staging trays of letters from
the DBCS sorting means or output stackers 22. The near-side
staging means preferably includes means defining a plurality of
letter tray storage or staging positions 50. In the illustrated
embodiment, the near-side staging means is substantially
identical to the sweep rack 30 and includes (see Figs. 1, 3 and
5) a modular sweep rack 54 also preferably fixed to the floor.
The sweep rack 54 defines three levels of letter tray staging
positions 50, with each level being generally aligned with a
respective level of DBCS output stackers 22. Bach level includes
a plurality of staging positions 50, with each staging position
50 being generally aligned with a respective output stacker 22.
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Adjacent staging positions on each shelf are separated by
separator strips 42 (Fig. 5) on the upper surface of the shelf.
The sweep rack 54 is made of modules 56 tFig. 1). Each module 56
of the sweep rack 54 is approximately 110 inches long and
includes eight letter tray staging positions 50 per level.
Located on top of the sweep rack 54 is a non-powered skate wheel
conveyor 58 (Figs. 3 and 5), the reason for which is explained
below.
The apparatus 10 also comprises means separate from the
DBCS 14 for automatically storing or staging letters from the
DBCS dispensing means or output stackers 22, means separate from
the DBCS for automatically storing or staging letters or letter
trays for input to the DBCS receiving means, means for
automatically presenting letters or letter trays in proper order
for the second pass through the DBCS 14, means for automatically
storing or staging letters from the output stackers 22 after the
second pass, and means for automatically presenting letters or
letter trays in proper order for conveyance after the second
pass. All of the foregoing preferably include (see Figs. 1-3 and
5) an automatic storage and retrieval system 62 located adjacent
the near side of the DBCS 14.
The automatic storage and retrieval system 62 includes
means defining a plurality of storage or staging locations 66.
While various storage location defining means can be employed, in
20~6701 ~
the illustrated embodiment such means includes (see Figs. 2 and
3) a modular staging or storage rack 70 mounted on top of the
near-side sweep rack 54. The storage rack 70 is made of modules
74. Each module 74 is approximately 110 inches long so that one
staging rack module 74 is mounted on top of each sweep rack
module 56. Each staging rack module 74 includes (see Fig. 3) a
frame 78 mounted on top of the sweep rack 54, seven vertically
spaced shelves 82, and cantilever supports 86 which are supported
by the frame 78 and which support the shelves 82. Each shelf 82
has a continuous upwardly facing horizontal surface that defines
a number of horizontally spaced staging locations 66. Use of the
cantilever supports 86 allows the shelves 82 to be supported such
that there are no partitions between adjacent letter tray staging
locations 66. Also, the top of the sweep rack 54 defines an
additional level of letter tray staging locations 66, so that the
sweep rack 54 and the storage rack 70 define eight levels of
staging locations, and a plurality of bays of staging locations,
with each bay including eight vertically aligned letter tray
locations.
The automatic storage and retrieval system 62 is
provided with (see Figs. 16-19) a track assembly 88 for reasons
more fully explained below. The track assembly 88 is supported
on a suitable supporting surface such as the floor, and in the
particular embodiment illustrated, includes a track that is
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preferably an elongated cylindrical rail member 88a extending
horizontally adjacent the rack system. The underside of the rail
member 88a i9 fixed to support members 88b which are spaced
axially along the rail member 88a and which are mounted on a
channel-shaped base 88c. Suitable means such as fasteners 88d
are provided to secure the components of the track assembly 88
together. The automatic storage and retrieval system also
includes (see Fig. 16) an upper rail 89 which is preferably
supported by the storage rack 70.
The automatic storage and retrieval system 62 also
includes (see Figs. 1-3~ a storage and retrieval machine 90.
While the storage and retrieval machine 90 can be used in a wide
variety of storage and retrieval applications, in the illustrated
arrangement the machine 90 receives trays of letters from the
DBCS 14 and presents letter trays 46 for input to the DBCS 14.
The storage and retrieval machine 90 is also operable to stage
letter trays 46 in and retrieve letter trays 46 from the staging
locations 66 in the staging rack 70.
The storage and retrieval machine 90 includes (see Fig.
16) a chassis or base 92, and means for supporting the base 92
for movement along the track assembly 88 so that the storage and
retrieval machine 90 is horizontally moveable relative to the
staging rack. While various supporting means can be employed, in
the illustrated arrangement the supporting means includes (see
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2~96701
Fig. 16) a pair of linear ~lide assemblies 93 supporting the base
92 on the rail member 88a. Referring to Figs. 17 and 19, each
slide assembly 93 includes a V-block 93a mounted (via fasteners
93b) to the underside of the base 92, and two oppositely axially
inclined linear slides 93c mounted on the V-block 93a with
fasteners 93d. The linear slides 93c provide substantially
frictionless sliding engagement between the storage and retrieval
machine 90 and the rail member 88a. Suitable slide assemblies
are produced by Thomson Industries, Inc. of Port Washington, New
York, and are sold under the name Roundway.
The storage and retrieval machine 90 also includes a
mast 94 (see Fig. 16) extending vertically from the base 92, a
carriage 98, and shuttle means for sliding a load onto and off
the carriage 98 without exerting an upward force on the load.
The upper end of the mast 94 is supported for movement along the
upper rail 89 by a pair of wheels or rollers 99 (one is shown in
Fig. 16) that are mounted on the mast 94. The shuttle means
preferably extends above the load and includes (see Fig. 6) a
shuttle or extractor mechanism 102 that is horizontally moveable
relative to the carriage 98 for placing letter trays 46 in and
extracting letter trays 46 from the staging locations 66 in the
storage rack 70. While the illustrated apparatus 10 has only one
storage rack on one side of the storage and retrieval machine 90,
it should be understood that the storage and retrieval machine 90
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is capable of accessing a storage rack on the other side of the
storage and retrieval machine 90 as well. Thus, the extractor
102 is extendable from both sides of the carriage 98.
To move the storage and retrieval machine 90
horizontally, means are provided for moving the base 92 along the
rail member 88a. While various moving means can be employed, in
the illustrated arrangement such means includes a drive mechanism
103. As shown in Fig. 16, the drive mechanism 103 includes drive
and idler wheels or sprockets 103a and 103b, respectively,
supported adjacent opposite ends of the rail member 88a, and a
toothed belt 103c trained around the sprockets 103a and 103b and
connected (Fig. 21) at its opposite ends to the opposite ends of
the base 92. The belt 103c is preferably a POLY CHAIN GT belt
manufactured by Gates. A stationary motor 103d is drivingly
connected to the drive sprocket 103a via a gear reducer to pull
the storage and retrieval machine back and forth along the rail
member 88a.
Means are also provided for supporting the carriage 98
on the mast 94 for vertical movement relative thereto. In the
illustrated arrangement (see Fig. 16) the means for supporting
the carriage 98 on the mast 94 includes a mounting assembly 104
including a pair of spaced apart vertically extending cylindrical
rods 104a and 104b. The rods 104a and 104b are fixed to a
support bracket 104c that is mounted on the mast 94 by fasteners
2096701 ~
104d or by other suitable means. The mounting assembly 104 also
includes (Fig. 16) upper and lower bearing assemblies 104e for
supporting the carriage 98 for vertical sliding movement along
the rods 104a. The upper and lower bearing assemblies 104e are
preferably identical and the upper bearing assembly is
illustrated in more detail in Fig. 20. Each bearing assembly
104e includes a pair of spaced apart pillow blocks 104f and 104g
fixed to the carriage 98, and a linear bearing 104h mounted in
each pillow block. The bearing 104h in block 104f slideably
receives the rod 104a, and the bearing 104h in block 104g
slideably receives the rod 104b. Each linear bearing 104e
extends in excess of 180 around the associated rod 104a or 104b.
Means are also provided for selectively moving the
carriage 98 up and down the mast 94. In the illustrated
arrangement (Fig. 16) the moving means includes a motor (not
shown) supported on the base 92 for driving a drum 105a. The
moving means also includes a pulley 105b rotatably supported on
top of the mast 94, and a cable 105c reeved around the drum 105a
and over the pulley 105b and connected to the carriage 98 via
(Fig. 20) a mounting block lO5d.
The carriage 98 and a first construction of the
extractor 102 are more particularly illustrated in Figs. 6
through 11. The carriage 98 includes (see Figs. 6 and 7) a frame
106 providing an upwardly facing surface 110 for supporting a
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letter tray 46. The extractor 102 includes an upper plate or top
member 114 preferably fixed to the carriage frame 106 in upwardly
spaced, parallel relation to the tray supporting surface 110.
The extractor 102 also includes an intermediate plate or member
118 which is located below the top member 114 and which is
supported by the top member 114 for horizontal sliding movement
relative thereto. The extractor 102 also includes a lower plate
or bottom member 122 which is located below the intermediate
member 118 and which is supported by the intermediate member 118
for horizontal sliding movement relative thereto and thus
relative to the top member 114.
More particularly, as best shown in Fig. 7, the
intermediate member 118 includes, adjacent each corner thereof,
an upwardly offset, horizontally extending mounting flange 126.
Extending downwardly from each of the flanges 126 is an H-shaped
bearing block or slide 130 defining both an outwardly opening
bearing track 134 and an inwardly opening bearing track 138. A
pair of bearing supporting members 142 extend downwardly from the
top member 114. One of the bearing supporting members 142 has
mounted thereon an upper slide or bearing strip 146 slidably
received in the bearing track 134 of one of the bearing blocks
130, and the other bearing supporting member 142 has mounted
thereon a bearing strip 146 slidably received in the bearing
track 134 of the other bearing block 130. The bearing strips 146
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support the intermediate member 118 for horizontal sliding
movement relative to the top member 114. Similarly, a pair of
bearing supporting members 147 extend upwardly from the bottom
member 122. One of the bearing supporting members 147 has
mounted thereon a lower slide or bearing strip 148 slidably
received in the bearing track 138 of one of the bearing blocks
130, and the other bearing supporting member 147 has mounted
thereon a bearing strip 148 slidably received in the bearing
track 138 of the other bearing block 130. The bearing strips 148
support the bottom member 122 for horizontal sliding movement
relative to the intermediate member 118. The bearing strips 146
and 148 can be made of any suitable low-friction material.
Means are provided for extending and retracting the
extractor 102, i.e., for causing sliding movement of the
intermediate and bottom members 118 and 122 relative to the top
member 114. While various extending and retracting means can be
employed, in the illustrated arrangement this means includes (see
Figs. 6 and 7) a drive motor 150 mounted on the top member 114.
The motor 150 is reversible and drives a sprocket 154 (Figs. 9
and 10) which is located below the top member 114 and which
rotates about a vertical axis 158. The means for extending and
retracting the extractor 102 also includes an idler sprocket 162
rotatably supported by the top member 114, and a drive chain 166
which is driven by the drive sprocket 154, which passes around
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the idler sprocket 162, which has a first end fixed to the
intermediate member 118 adjacent the right end thereof (as shown
in Fig. 8), and which has a second end fixed to the intermediate
member 118 adjacent the left end thereof (as shown in Fig. 8).
Thus, as is apparent from viewing Figs. 8 and 10, clockwise
rotation of the drive sprocket 154 pulls the intermediate member
118 to the left relative to the top member 114, and
counterclockwise rotation of the drive sprocket 154 pulls the
intermediate member 118 to the right relative to the top member
114.
The means for extending and retracting the extractor
102 also includes (see Figs. 8 and 10) an idler pulley 170
pivotally mounted on the inter~ te member 118, a cable 174
which is reeved around the pulley 170 and which has one end fixed
to the top member 114 and an opposite end fixed to the bottom
member 122, an idler pulley 17~ rotatably mounted on the
intermediate member 118, and a cable 182 which is reeved around
the pulley 178 and which has one end fixed to the top member 114
and an opposite end fixed to the bottom member 122. As is
apparent from viewing Fig. 8, movement of the intermediate member
118 to the left causes movement of the pulley 170 relative to the
top member 114, and such movement of the pulley 170 causes the
cable 174 to pull the bottom member 122 to the left relative to
the intermediate member 118. Movement of the intermediate member
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118 to the right relative to the top member 114 causes movement
of the pulley 178 to the right relative to the top member 114,
and such movement of the pulley 178 causes the cable 182 to pull
the bottom member 122 to the right relative to the intermediate
member 118. The cable and pulley arrangements cause the bottom
member 122 to move twice as fast as the intermediate member 118.
Thus, clockwise rotation of the drive sprocket 154
causes movement of the intermediate member 118 and bottom member
122 to the left (as shown in Fig. 8), and counterclockwise
rotation of the drive sprocket causes movement of the
intermediate member 118 and bottom member 122 to the right.
Accordingly, the extractor 102 is operable between a
retracted condition (Fig. 6) and an extended condition (Figs. 10
and 11). In the retracted condition, the intermediate and bottom
members 118 and 122 are aligned directly beneath the top member
114 and contained within the carriage so that the members are out
of the way and protected during movement of the carriage. In the
extended condition, the intermediate member 118 extends outwardly
in one direction relative to the top member 114, and the bottom
member 112 extends outwardly in the same direction relative to
the intermediate member 118.
Means are provided on the bottom member 122 for
selectively engaging an object ~i.e., a letter tray 46) beneath
the bottom member 122 so that the object moves horizontally in
HARN9009
2~96701
common with the bottom member 122. While the engaging means can
be configured to move various objects to permit the storage and
retrieval device 90 to be used in other applications, in the
illustrated arrangement the engaging means includes (see Figs. 6,
8, 10 and 11) a pair of generally U-shaped members or hoops 186
each having opposite ends pivotally mounted on the bottom member
122. Referring to Fig. 6, each of the hoops 186 is pivotally
moveable between an upper position (shown in solid lines) wherein
it extends substantially parallel to the bottom member 122, and a
lower position (shown in phantom) wherein it extends transversely
and downwardly relative to the bottom member 122. When the hoops
186 are in their upper positions, the bottom member 122 can pass
over a letter tray 46 located in the storage rack 70 without
interference between the hoops 186 and the letter tray 46. When
the hoops 186 are moved to their lower positions, each of the
hoops 186 is engageable with a respective end of the letter tray
46 so as to substantially prevent horizontal movement of the
letter tray 46 relative to the bottom member 122.
Means are provided for selectively pivoting the hoops
186 relative to the bottom member 122. Such means preferably
includes means for simultaneously moving the hoops 186 to their
upper positions and for simultaneously moving the hoops 186 to
their lower positions. While various hoop pivoting means can be
employed, in the embodiment illustrated in Figs. 6, 8, 10 and 11
H~RN9009
2096701
such means includes, for each of the hoops 186, a torsional motor
or solenoid 190 (Figs. 6 and 8) which is mounted on the bottom
member 122 for movement therewith and which is drivingly
connected to one end of the hoop. The solenoid 190 is biased so
as to bias the hoop to its upper position, and actuation of the
solenoid 190 causes movement of the hoop to its lower position.
Means are provided for selectively retaining the hoop in its
lower position. This means preferably includes (see Figs. 6 and
11) a cam 194 fixed to the hoop for pivotal movement therewith
about the solenoid axis, and a linear motor or solenoid 198
having an outwardly biased plunger 202 engaging the cam 194.
When the hoop moves to its lower position, pivotal movement of
the cam allows the plunger 202 to "fall off n a step 206 on the
cam, and the plunger thereafter interferes with the step so as to
prevent pivotal movement of the cam and the hoop in the opposite
direction. Engagement of the step 206 by the plunger 202
therefore prevents movement of the hoop from its lower position.
Accordingly, neither of the solenoids needs to be actuated in
order to retain the hoop in its lower position. In order to
return the hoop to its upper position, the linear solenoid is
actuated. This retracts the plunger so that the plunger 202 no
longer interferes with the step 206, and this allows the natural
bias of the torsional solenoid 190 to return the hoop to its
upper position.
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This arrangement m; n; m;zes the amount of electricity
needed to operate the hoops 186. The torsional solenoids 190
naturally bias the hoops 186 to their upper positions. Only a
momentary current is necessary to move the hoops 186 to their
lower positions. Thereafter, the spring bias of the linear
solenoids 198 retains the hoops 186 in their lower positions.
Only a momentary actuation of the linear solenoids 198 is
necessary to return the hoops 186 to their upper positions. Once,
the steps 206 clear the plungers 202 of the linear solenoids 198,
the linear solenoids 198 can be deactivated.
The carriage and extractor assembly operates as
follows. When the supporting surface 110 of the carriage is
aligned with a shelf 82 in the staging rack 70, the drive
sprocket 154 is rotated clockwise so as to extend the bottom
member 122 above a letter tray 46 on the shelf. The hoops 186
(or only the outer hoop if the third embodiment is employed) are
then moved to their lower positions to capture the letter tray,
46, and the drive sprocket is rotated counterclockwise so as to
retract the bottom member 122. Engagement of the letter tray 46
by the hoops 186 causes the letter tray 46 to move with the
bottom member 122 and slide off the shelf onto the carriage
supporting surface 110. Location of the bottom member 122
immediately above the letter tray 46 substantially prevents
letters from coming out of the tray 46 during movement of the
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2096701
tray 46. The hoops 186 remain in their lower positions during
movement of the carriage relative to the staging rack 70.
To prevent the storage and retrieval machine 90 from
being derailed, means are provided on the base 92 for preventing
its upward movement relative to the rail member 88a. While
various movement prevention mean~ can be employed, in the
illustrated arrangement such means includes (see Fig. 16) a pair
of retainer assemblies 208 positioned outside of the slide
assemblies 93 adjacent the opposite ends of the base 92. As
shown in Figs. 17 and 18, each retainer assembly 208 includes a
mounting or pillow block 208a fixed to the base 92 by suitable
means such as fasteners 208b, and an arcuate bushing bearing or
retainer 208c. The retainer 208c includes an inner bearing
surface 208d that extends beneath the rail member 88a and in
excess of 180 around the rail member 88a to provide an opening
208e adjacent the underside of the rail member 88a. The bearing
surface 208d defines a bore which comml~n;cates with the opening
208e and through which the rail member 88a extends. The opening
208e accommodates the support members 88b. During normal
operation of the storage and retrieval machine 90, the bearing
surface 208d preferably remains slightly spaced from the rail
member 88a, slideably contacting the rail member 88a only when
the base 92 becomes slightly misaligned with respect to the rail
member 88a.
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2C96701
The apparatus 10 further comprises means for
transporting or conveying letter trays from the opposite-side
sweep rack 30 to the storage and retrieval machine 90. The
transporting means includes (see Figs. 1) a horseshoe-shaped
lower or input tray transport system or conveyor 210. The input
tray transport system 210 includes (see Fig. 4) an upstream
portion running through the opposite-side sweep rack 30 below the
sweep rack staging positions 34. This portion of the tray
transport system 210 runs from left to right as shown in Fig. 1.
The tray transport system 210 also includes (see Fig. 3) a
downstream portion running through the near-side sweep rack 54
beneath the staging positions 50 thereof. This portion of the
tray transport system 210 runs from right to left as shown in
Fig. 1. The tray transport system 210 also includes a middle
portion which runs from top to bottom in Fig. 1 and which
connects the upstream and downstream portions of the tray
transport system 210. As shown in Fig. 5, the tray transport
system 210 jogs inwardly (downwardly in Fig. 1) at its downstream
end. The upstream end of the tray transport system 210 is
referred to hereinafter as the tray induction station 212
(Fig. 1), because trays can be placed on the tray transport
syqtem at this point. Several motors (not shown) drive the tray
transport system 210.
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~096701 H^~
As shown in Figs. 5 and 15, pick-up and delivery
powered conveyor rollers (P&D station) 214 are located adjacent
the downstream end of the tray transport system 210 and run from
right to left in Fig. 1. Trays on the input tray transport
system 210 are deposited onto the P&D station 214, which is
accessible by the storage and retrieval machine 90. A set of
gravity rollers 222 is located adjacent the downstream end of the
P~D station 214. The rollers 222 define an operator station.
The gravity rollers 222 operate by gravity and present trays to
the feed operator. If a tray 46 at the P&D station 214 is not to
be retrieved by the storage and retrieval machine 90, the P&D
powered rollers 214 convey the tray 46 to the operator station
gravity rollers 222 so that the tray 46 is delivered to the
operator. This will happen when the control system cannot read a
tray bar code.
When a tray 46 in the opposite-side sweep rack 30
becomes full, or when a DBCS pags is ended, an operator removes
the tray 46 from its staging position in the opposite-side sweep
rack 30 and places the tray 46 on the tray transport system 210.
The tray 46 is then conveyed to the pick-up and delivery station
214 where the tray 46 can be retrieved by the storage and
retrieval machine 90 or allowed to pass to the operator (in the
event of a bar code "no-read").
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209670~.
The apparatus 10 also comprises means for conveying or
transporting letter trays from the near-side sweep rack 54 to the
storage and retrieval machine 90. This transporting means
preferably includes (see Figs. 3 and 15) the input tray transport
system 210 and three additional output belts or conveyors 226
running through the near-side sweep rack 54. Each of the output
belts 226 runs from right to left as shown in Fig. 1. Each belt
226 is located immediately behind an associated level of staging
positions 50 such that a sweep operator can push letter trays
from any one of the staging positions 50 onto the associated
output belt 226. Means are provided for driving the belts 226.
Such means includes (see Fig. 5) a drive motor 230 selectively
clutched to drive each of the belts 226.
As shown in Figs. 1, 5 and 15, P&D powered conveyor
rollers (P&D rollers or P&D station) 231 are located adjacent the
downstream end of each of the output belts 226 and run from right
to left in Fig. 1. Each set of P&D conveyor rollers 231 is
identical to the P&D conveyor rollers 214. A tray 46 on one of
the output belts 226 is deposited onto the associated set of P&D
powered conveyor rollers 231, which i8 accessible by the storage
and retrieval machine 90. A set of gravity rollers 233 is
located adjacent the downstream end of each P&D station 231.
Each set of gravity rollers 233 is identical to the gravity
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HARN9009
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rollers 222. Each set of rollers 233 defines an operator
station, where the trays are accessible by the feed operator.
Means are provided for driving the powered conveyor
rollers 214 and 231. Such means preferably includes (see Fig. 5)
a drive motor 234 selectively clutched to drive each of the sets
of rollers 214 and 231.
Adjacent the P&D station 214 at the downstream end of
the input tray transport system 210 is a bar code scanner pair
(not shown) that is connected to the control system 238. The
control system 38 reads the bar code on any tray 46 before that
tray 46 reaches the input P&D station 214.
The apparatus 10 operates as follows:
It should be recalled that letters are sorted to
individual area routes by passing the letters twice through the
DBCS 14. Letters are put into the receiving means 18 for first
pass, and the DBCS 14 partially sorts the letters and dispenses
the letters to the output stackers 22. The letters are then put
into the receiving means for second pass, and the DBCS 14
dispenses to the output stackers 22 letters sorted to the
individual carrier routes.
Before mail sortation by the DBCS 14 may begin, the
sweep racks 30 and 54 must be staged or supplied with empty mail
trays. The empty trays are distributed on the sweep racks 30 and
54 by placing stacks of empty trays on the non-powered skate
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2096701 HARN~
wheel conveyor 58 at the uppermost level of the sweep racks and
pushing the trays along in slugs. An empty tray 46 is placed in
each of the three sloped staging positions in the sweep racks 30
and 54. In addition, eight to nine empty trays are positioned on
the top level of the sweep racks at each horizontal position.
Alternatively, stacks of nested empty trays are placed
on the input tray transport system 210 at the tray induction
station 212. Three to six empty trays are placed in each stack.
The stacks of empty trays are allowed to travel along the input
tray transport system 210 to the downstream end of the tray
transport system 210. Once all staging positions are staged with
an empty tray 46 and there are sufficient extra empty trays
staged on the top level of the sweep racks, the input tray
transport system 210 is cleared of all empty trays.
Next, a bar code tag 47 is placed on each of the trays
staged in the staging positions in the sweep racks. The bar code
label 47 identifies the DBCS output stacker 22 that the mail is
transferred from as it is placed in the empty tray 46. The
preprinted labels 47 are inserted into existing plastic sleeves
provided on the mail trays 46.
All carts of trayed mail to be processed at the DBCS 14
are delivered to the tray induction station 212 at the upstream
end of the input tray transport system 210. The trays are
unloaded onto the input tray transport system 210 and allowed to
-40-
2096701 HARN~
travel to the P&D station 214 (see Fig. 5) at the downstream end
of the input tray transport system 210. At this point in the
operation the staging rack 70 is empty.
As the trays are processed at the P~D station 214, the
bar code on each tray 46 is scanned by the bar code scanner pair.
Each tray of mail to be processed at the DBCS 14 arrives with a
bar code label that was attached at the previous station. A
positive read of the bar code label informs the apparatus 10 that
the tray 46 requires first pass processing.
The trays arriving at the P&D station 214 are stored by
the storage and retrieval machine 90 in the staging rack 70. Any
empty location in the staging rack 70 may be used. To m; n;m; ze
the access time of the storage and retrieval machine 90, the
trays are first placed in the staging rack 70 in the positions
closest to the output P&D stations 231. The three levels of
output belts 226 in the staging rack 70 serve as input positions
from the sweep rack 54 at the end of both sortation passes and
are not accessible by the storage and retrieval machine 90.
Sufficient staging rack capacity has been provided to
stage all of the trays requiring first pass processing. There
are eight levels in each bay of the staging rack 70. When
approximately 80~ of the available capacity in the staging rack
70 i9 utilized, the storage and retrieval machine 90 no longer
stores the incoming trays. The trays of mail to be sorted on
-41-
2096701 ~
first pass are then allowed to queue along the entire length of
the input tray transport system 210.
When first pass processing of the mail is started, the
storage and retrieval machine 90 begins to deliver trays to the
DBCS operator via the operator stations. The storage and
retrieval machine 90 retrieves the trays arriving at the P&D
station 214 at the end of the tray transport system 210 and
places the trays on one of the three output P&D stations 231
(i.e., on one of the sets of powered conveyor rollers 231). From
here the trays 46 are moved onto the gravity rollers 233 and thus
to the feed operator. If a deposit position is not available at
one of the output P&D stations 231, the trays are placed in the
staging rack 70. The trays of mail on the input tray transport
system 210 are the first trays delivered to the DBCS feed
operator by the apparatus 10.
After the trays on the input tray transport system 210
have been processed, the storage and retrieval machine 90 begins
to retrieve the trays of mail waiting for first pass processing
in the staging rack 70 and delivers them to the output P&D
stations 231. From here the trays 46 are moved onto the gravity
rollers 233 and thus to the feed operator. All of the mail to be
processed on first pass has the same priority and is retrieved
accordingly.
-42-
HARN9009
2096701
The sweep operator transfers the sorted first pass mail
from the DBCS output stackers 22 to the empty trays in the sweep
racks 30 and 54. When a tray 46 is completely filled before
first pass is over, m~n;ng there are multiple trays of sorted
mail from the same DBCS output stacker 22, the full tray 46 is
placed on the input tray transport system 210 and travels to the
input conveyor P~D station 214. Such a full tray 46 is referred
to as an "overflow" tray. If the input tray transport system 210
is not clear at the position where the overflow tray 46 occurs
(the input tray transport system 210 may contain trays waiting
for first pass sortation), the tray is placed on the top level of
the sweep rack. The trays of mail placed on the top of the sweep
racks are placed on the input tray transport system 210 when a
clear window appears. The reason the trays on the input tray
transport system 210 are processed before the trays in the
staging rack 70 is to help maintain open windows on the input
tray transport system 210.
As the trays are being processed and as first pass
continues, more trays may be introduced at the tray induction
station 212 on the input tray transport system 210. As these
trays arrive at the P~D station 214 the bar code scanner pair
scans the label end of the tray. If a label is read without the
first pass bar code 47, the tray is scheduled for immediate first
pass processing. When a valid read of a first pass label 47 with
HARN9009
2096701
the corresponding DBCS output stacker number occurs, the tray is
an overflow and is staged in the staging rack 70. This tray
remains in the staging rack 70 waiting to be sequenced for second
pass processing. The information associated with this tray is
entered in the control system database.
First pass sortation ends as all unsorted trays have
been processed. The computer control system maintains a count of
the trays in the staging rack 70 that are to be sorted on first
pass and dynamically updates and displays this information on the
control monitor. To reduce the time from the end of first pass
to the start of second pass, all overflows are placed on the
input tray transport system 210 and staged in the staging rack 70
before the end of first pass processing. At this point in the
operation the input tray transport system 210 should be clear.
The first step in preparing to process the mail for
second pass is to verify that all of the trays that are overflows
for any DBCS output stacker 22 have been placed on the input tray
transport system 210.
The sweep operator completely sweeps all first pass
mail from each DBCS output stacker 22 and places it in the
corresponding tray at the sloped positions in the sweep racks 30
and 54.
H~UN9009
2096701
Next, the sweep operator places all the trays from the
three levels of opposite-side sweep rack 30 onto the input tray
transport system 210. It is preferable that these trays be
placed on the input tray transport system 210 in exact DBCS
output stacker sequence. Not all of the trays from the opposite-
side sweep rack 30 are able to queue on the input tray transport
system 210. Only the m;n;mllm number of trays need to be staged
in the staging rack 70 before second pass processing may begin.
This leaves the input tray transport system 210 completely loaded
as second pass processing begins.
Each of the trays at the near-side sweep rack 54 (even
empty trays) is pushed onto one of the three belts 226. Care
must be taken to correctly position these trays to ensure the
proper orientation on the belts 226. (Overflow trays are not
pushed onto the belts 226 in the sweep rack 54 during processing.
They are placed on the input tray transport system 210 to be
staged in the storage and retrieval machine 90.)
At this point all first pass overflows are in the
staging rack 70, the three belts 226 hold the three levels of
first pass trays inserted from the near-side sweep rack 54, and
the input tray transport system 210 is completely full of first
pass trays arriving from the opposite-side sweep rack 30.
When second pass processing is started, the three
output belts 226 begin to deliver the trays to the three output
-45-
2096701 """~,
P&D stations 231. The trays are advanced into the P&D stations
231 in the exact sequence to correspond to the first DBCS output
stacker locations. Only one tray at a time is indexed from the
output belt 226 through the P&D station 231 to the associated
rollers 233 and thus to the feed operator. Tray sequencing is
maintained by presenting only one tray at a time to the feed
operator.
All staging positions 34 and 50 are now re-supplied
with empty trays from the top level of the sweep racks 30 and 54.
The bar code labels 47 printed by the DBCS 14 are inserted in the
plastic sleeves attached to the trays 46. The bar code labels 47
contain carrier route and dispatch information.
The control system keeps track of the overflow trays 46
and deliver~ them as required to match the trays from each DBCS
output stacker 22. The overflows are queued in the output P&D
stations 231 by the storage and retrieval machine 90 and are
released to the operator stations (the rollers 233) under the
direction of the control system. Because the overflow trays are
completely full, they are the first trays delivered to the DBCS
feed operator.
After all the first pass trays on the three levels of
belts 226 in the sweep rack 54 have been processed, the storage
and retrieval machine 90 begins to deliver to the P&D stations
231 (i.e., to the powered conveyor rollers 231) the trays from
-46-
2096701 HARN~
the opposite-side sweep rack 30 that have been placed in the
staging rack 70.
At the same time trays are being delivered to the
output P&D stations 231 for second pass processing, the storage
and retrieval machine 90 i9 transferring trays from the input P&D
station 214 to the staging rack 70. The control system continues
to dispatch trays to the operator station one at a time in order
of DBCS sequence number. These first pass trays are arriving on
the input tray transport system 210 from the opposite-side sweep
rack. The trays on the input tray transport system 210 are
staged as soon as a location in the staging rack 70 is available.
The trays on the input tray transport system 210 are in order as
placed there by the sweep operator.
The bar code label 47 on the tray identifies a DBCS
output stacker location. This data is sc~nne~ by the bar code
scanner pair and stored in the control system database. This
allows the control system to track the overflow trays which are
staged by the storage and retrieval machine 90.
The sweep operator performs the same operations on
second pass that were performed on the first pass. As trays are
filled and overflows occur they are placed on the input tray
transport system 210. The overflow trays are placed on the top
level of the sweep racks if open windows are not available on the
input tray transport system 210. These trays are moved to the
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input tray transport system 210 as soon as open positions are
available.
All of the overflow trays from second pass processing
are to be in the staging rack 70 before the mail is dispatched.
The sweep operator verifies that all overflows have been placed
on the input tray transport system 210, delivered to the input
conveyor P&D station 214, and then staged in the staging rack 70.
The sweep operator completely sweeps all second pass
mail from each DBCS output stacker 22 and places it in the
corresponding tray at the sloped positions in the sweep rackq 30
and 54. The operator then pushes all of the trays on the near-
side sweep rack 54 onto the three output belts 226.
The trays in the opposite-side sweep rack 30 are placed
on the input tray transport system 210 in sequence and delivered
to the input P&D station 214. Because of the number of trays at
the opposite-side sweep rack 30 it may be necessary to place only
half of the trays on the input tray transport system 210.
Placement of these trays in dispatch carts at the operator
stations 233 will free the input tray transport system 210 to
accept the remaining trays from the opposite-side sweep rack 30.
All of the trays to be dispatched are delivered
directly to dispatch carts. Before dispatching the mail, all
second pass overflow trays are in the staging rack 70, the three
belt~ 226 hold the three levels of second pasq trays inserted
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H~N9009
from the near-side sweep rack ~4V~a~d ~e input tray transport
system 210 is completely full of second pass trays arriving from
the opposite-side sweep rack 30.
When dispatch is started, the three belts 226 begin to
deliver the trays to the three P&D stations 231. The trays are
advanced onto the gravity rollers 233 and to the operator in the
exact sequence corresponding to the first DBCS output stacker
locations. The control system tracks the trays on the belts 226
and directs the storage and retrieval machine 90 to retrieve from
the staging rack 70 any overflows to match the trays that are
staged at the head or downstream ends of output belts 226. The
storage and retrieval machine g0 delivers these overflow trays to
one of the three sets of powered conveyor rollers 231. The
control system comm~n~s the dispensing of trays from either the
output belts 226 or the output P&D stations 231 whenever all of
the operator stations 233 are determined to be empty. Only one
tray at a time is indexed onto one of the three sets of rollers
233 for consistent sequencing of trays to the operator.
Once all of the trays on the three belts 226 have been
delivered to the operator and loaded onto dispatch carts, the
trays from the opposite-side sweep rack 30 are dispatched. These
trays are loaded directly from the input tray transport system
210 onto dispatch carts via operator station 222. Overflows are
brought out to match trays which are staged at the head or
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2096701
downstream end of the input tray transport system. The control
system either dispatches from the lowest operator station 222 or
delivers overflows to the operator stations 233.
Empty dispatch carts are used by the operators for
loading the trays 46. The loaded dispatch carts go directly to
the shipping dock. After all the trays are on carts and on the
way to dispatch, the sweep racks are again staged with empty
trays.
An apparatus 310 which is an alternative embodiment of
the invention and which includes a bar code sorter 314 rather
than a delivery bar code sorter is shown in Fig. 12. The
apparatus 310 comprises an automatic storage and retrieval system
362 including a storage and retrieval machine 366 and a staging
rack 370 on each side of the storage and retrieval machine 366.
Each rack 370 includes four bays of staging positions. The
apparatus 310 also comprises a conveyor 374 between the bar code
sorter 314 and the automatic storage and retrieval system 362.
Thus, the invention provides a letter sorting apparatus
including a letter sorting machine and an automatic storage and
retrieval system. It automatically stages letters sorted and
dispensed by the letter sorting machine and that automatically
stages letters for input into the letter sorting machine for
sorting. The automatic storage and retrieval system includes one
or more discrete storage rack modules each having standard shells
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with continuous upwardly facing surfaces that define a plurality
of staging or storage locations, and a storage and retrieval
machine that is operable to store objects, such as letter trays,
in and to retrieve objects from designated storage locations.
Transporting means, such as a conveyor, is employed to feed
objects to be stored to the storage and retrieval machine from
temporary storage positions. In the particular embodiment
described hereinafter, letters to be sorted by the letter sorting
machine are staged by the storage and retrieval machine for input
into the letter sorting machine, and, after sorting, are
transported from the letter sorting machine into the storage and
retrieval machine which thereafter stores the letters in and
retrieves the letters from storage locations on the storage rack
modules. The storage and retrieval machine includes a
horizontally movable base, a vertical mast on the base, a
vertically movable carriage supported on the mast, and an
extractor that is generally inverted relative to prior art
arrangements and that is operable to slide a load (i.e., a letter
tray) onto and off of the carriage without exerting an upward
force on the load. More particularly, the extractor includes an
upper most plate member fixed on the carriage, and one or more
successively lower plate members that are horizontally movable
relative to the proceeding plate member thereabove. Suitable
moving means, such as a motor, is provided to move the movable
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2096701
plate members between an extended position wherein the lower most
plate member is positioned directly above an object in a storage
location without interference from the shelves, and a retracted
position wherein the movable plate members are vertically aligned
within the carriage. The lower most plate member is provided
with at least one hoop-like member selectively movable between a
raised position and a lowered position wherein it is engageable
with an object to be moved so that when the lower most plate
member is extended or retracted the object is slid with it to
move the object between the carriage and the desired storage
location. One or more motors are provided for moving the hoop-
like member.
An apparatus 410 which is an alternative embodiment of
the invention and which includes an optical character reader 414
rather than a delivery bar code sorter is shown in Fig. 13. The
apparatus 410 comprises an automatic storage and retrieval system
462 including a storage and retrieval machine 466 and a staging
rack 470 on each side of the storage and retrieval machine 466.
Each rack 470 includes one bay of staging positions, so that the
mast of the storage and retrieval machine 466 does not have to
move horizontally. The apparatus 410 also comprises a conveyor
474 between the optical character reader 414 and the automatic
storage and retrieval system 462.
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An apparatus 510 which is an alternative embodiment of
the invention and which includes a one-sided delivery bar code
sorter 514 rather than a two-sided delivery bar code sorter is
shown in Fig. 14. The apparatus 510 comprises a sweep rack 554
on the output side of the bar code sorter 514. The apparatus
also comprises a storage and retrieval system 562 including a
storage and retrieval machine 566 and a staging rack 570 on top
of the sweep rack 554. The sweep rack 554 has therein belts (not
shown) identical to the belts 210 and 226 of the apparatus 10,
rollers (not shown) identical to the rollers 214 and 222 of the
apparatus 10, and rollers 531 and 533 (one set is shown)
identical to the rollers 231 and 233 of the apparatus 10.
An alternative extractor or shuttle mechanism 602 is
illustrated in Figs. 22-26. Except as described below, the
shuttle mechanism 602 is identical to the shuttle mechanism 102,
and common elements have been given the same reference numerals.
In the shuttle mechanism 602, the opposite ends of the
hoop 186A are designated by reference numerals 604 and 606, and
the opposite ends of the hoop 186B are designated by reference
numerals 608 and 610. The end 604 of the hoop 186A has thereon
(see Fig. 25) a downwardly extending pivot arm 612, and the end
608 of the hoop 186B has thereon an upwardly extending pivot arm
614. The end 606 of the hoop 186A has thereon (see Fig. 24) an
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upwardly extending pivot arm 116, and the end 610 of the hoop
186B has thereon a downwardly extending pivot arm 618.
In the shuttle mechanism 602, the means for moving the
hoops 186 includes (see Fig. 25) a first link 620 extending
between the pivot arms 612 and 614 (and thus between the hoops
186A and 186B). The means for moving the hoops 186 also includes
(see Fig. 24) a second link 622 extending between the pivot arms
616 and 618 (and thus between the hoops 186A and 186B). Each of
the links 620 and 622 i8 movable substantially longitl~;n~lly in
opposite directions. The means for moving the hoops 186 also
includes a motor 626_fixed against horizontal movement relative
to the carriage 98. The motor 626 is preferably fixed to the
upper plate 114. The motor 626 is preferably a reversible brake
motor having (see Fig. 23) a horizontally extending output shaft
630 having opposite ends 632 and 634. The shaft end 632 has
thereon (see Fig. 25) a downwardly extending lever arm 636, and
the shaft end 634 has thereon (see Fig. 24) a downwardly
extending lever arm 638. The means for moving the hoops 186 also
includes means for drivingly connecting the motor 626 to the
hoops 186. Such connecting means preferably includes a cable and
pulley arrangemenS connecting the lever arm 636 to the link 620
and a cable and pulley arrangement connecting the lever arm 638
to the link 622.
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~09~701
The cable and pulley arrangement connecting the lever
arm 636 to the link 620 includes (see Figs. 23 and 25) a pulley
640 pivotally mounted on the upper plate 114 and fixed against
horizontal movement relative thereto, and a pulley 644 pivotally
mounted on the intermediate plate 118 and fixed against
horizontal movement relative thereto. The pulley 640 rotates in
a vertical plane, and the pulley 644 rotates in a non-vertical
and non-horizontal plane as best shown in Fig. 26. A cable 648
is trained over the pulleys 640 and 644 and has one end fixed to
the lower end of the lever arm 636 and an opposite end fixed to
the upper end of the pivot arm 614. As seen in Fig. 25,
counterclockwise movement of the lever arm 636 acts through the
cable 648 to cause clockwise movement of the pivot arm 614 and
thereby pivots the hoops 186 to their upper positions.
The cable and pulley arrangement connecting the lever
arm 638 to the link 622 includes (see Figs. 23 and 24) a pulley
652 pivotally mounted on the upper plate 114 and fixed against
horizontal movement relative thereto, a pulley 656 pivotally
mounted on the intermediate plate 118 and fixed against
horizontal movement relative thereto, and a pulley 660 pivotally
mounted on the lower plate 122 and fixed against horizontal
movement relative thereto. The pulleys 652 and 660 rotate in a
vertical plane, and the pulley 656 rotates in a non-vertical and
non-horizontal plane as best shown in Fig. 26. A cable 664 is
209 670 1 HA~
trained over the pulleys 652, 656 and 660 and has one end fixed
to the lower end of the lever arm 638 and an opposite end fixed
to the upper end of the pivot arm 616. As seen in Fig. 24,
counterclockwise movement of the lever arm 638 acts through the
cable 664 to move the pivot arm 616 counterclockwise and thereby
pivots the hoops 186 to their lower positions.
A second alternative extractor or shuttle mechanism 702
is partially illustrated in Fig. 27. Except as described below,
the shuttle mechanism 702 i9 identical to the shuttle mechanism
602, and common elements have been given the same reference
numerals.
In the shuttle mechanism 702, the pivot arms 612, 614,
616 and 618 all extend upwardly so that longitudinal movement of
either link 620 or 622 causes one of the hoops 186 to move to its
upper position and causes the other hoop 186 to move to its lower
position. For example, as seen in Fig. 27, counterclockwise
movement of the lever arm 616 moves the hoop 186A to its lower
position and moves the hoop 186B to its upper position.
Various features of the invention are set forth in the
following claims.
