Apparatus for sorting and distributing mail pieces

In an apparatus for sorting and distributing mail pieces, the mail pieces e introduced into an inlet module, then from the inlet module into a transporter and finally to an outlet module. Mail pieces are moved from a receiving station on to a continuous conveyor forming a part of the inlet module. The continuous conveyor has a number of transporting sections disposed in spaced generally horizontal planes. From the transporting sections mail pieces are transferred at a transfer station from transport pallets on to individual receptacles in the transporter. At a removal station spaced from the transfer station, mail pieces are removed by an extraction device from the individual receptacles on the transporter to containers on an output conveyor of the output module. The containers are formed to receive a plurality of mail pieces.

BACKGROUND OF THE INVENTION 
The present invention is directed to an apparatus for sorting and 
distributing mail pieces, such as letter mail, made up of an input module 
for the mail pieces, a transporter for moving individual mail pieces 
between the input module and an output module for the sorted mail pieces. 
A known problem with so-called letter mail is that the type of sorting and 
distribution of such mail pieces is very costly, particularly in terms of 
personnel, whether the distribution and allocation refers to individual 
cities and villages or to the distribution and allocation to individual 
streets and other receivers within the cities and villages. 
Mail distributing systems are known where mail pieces, particularly 
letters, are directed into individual compartments via belt conveyors 
after presorting and subsequent sorting. A letter placed into the system 
is provided with a code, the code is read at a corresponding place in the 
system, and the letter is then assigned to an indiVidual compartment by 
distributing conveying means. The following German patent No. DE-C-32 05 
652 is referred to only as an example. 
The known solution is suitable only for standard letter formats, as a rule, 
differences in size, thickness, and dimensioning can not be processed in 
such a system. Further, such a system is completely unsuitable for mailing 
periodicals, printed matter and the like. 
SUMMARY OF THE INVENTION 
Therefore, it is the primary object of the present invention to sort 
completely a collection of heterogeneous mail pieces and to assemble them 
in a sorted form where a rough sorting, as well as a detailed sorting, is 
possible in the same system or apparatus The apparatus is made up of an 
input module for receiving the mail pieces, and an output module for 
collecting the sorted mail with a transporter moving the mail pieces 
between the input module and the output module. The input module includes 
a continuous conveyor for receiving mail pieces at a receiving station 
from singulators or separators. The continuous conveyor includes a 
plurality of horizontally arranged vertically spaced transporting planes 
for directing the mail pieces into the transporter. The transporter 
comprises a multiplicity of circulating individual transporting units or 
receptacles. Transport pallets on the continuous conveyor of the input 
module also form transfer elements for placing the mail pieces from the 
pallets into assigned individual receptacles of the transporter. At least 
one extracting device is located on the transporter spaced from the 
transfer station for extracting or removing the mail pieces from the 
transporter and placing them in a conveyor in the output module where the 
mail pieces are collected in containers. 
In the invention, the sorting operation including transporting the sorted 
mail pieces, is provided in a transporter which is as independent as 
possible from the items being transported, that is, the format, weight, 
dimensions of the mail pieces need not be taken into account. 
From a supply container, which can be comparable to a container available 
at the outlet end of the system, each mail piece is fed from a separator 
to a continuous conveyor provided with forked pallets. The position of a 
mail piece can be determined at any time by a corresponding coding device. 
The mail piece, supplied to the continuous conveyor is then conveyed so 
that it is sorted from the individual pallets of the continuous conveyor 
to a collecting container with a transporter in the form of an individual 
conveying means forming an intermediate part of the apparatus. 
The equipment at the receiving station for transferring a mail piece onto 
the inlet module includes a gripping device with a wiping device. In 
addition, an oscillating drive and/or so-called format baffle plates can 
be provided for ensuring a certain pre-sorting according to size by 
mechanical means using size templates in a sloped position of the 
container or pallet receiving the unsorted mail pieces. 
It may be advisable if a combined pneumatic and mechanical gripping device 
is used for picking up the upper mail pieces, that, for example, the upper 
mail piece is drawn off or raised from the stack by only a short distance 
using the pneumatic conveyor whereby it can be completely gripped by the 
mechanical gripping device Such an arrangement has the advantage that the 
pneumatic gripping device need only expend a slight force, since it is not 
necessary for it to transport the total weight of the mail piece. 
Different suction grippers can be controlled based on information from a 
format and thickness detection device of the system, that is, only as many 
suction grippers are activated and controlled as are necessary based on 
the letter size to be gripped. 
It is also advisable to construct the carriers for the individual mail 
pieces as forked pallets, that is, the individual mail pieces are 
deposited on an individual fork or forked cage. With such an arrangement, 
it is advantageous to arrange the fork or forked cage as part of a 
transporting pallet movable around at least two different axes. 
Further, it is advantageous if the transporter receiving mail pieces from 
the input module is in the form of a continuous conveyor provided with a 
multiplicity of individual receiving positions each formed as a forked 
receiver with the conveyor being a substantially oval shaped multi-tier 
circulating conveyor, for example, with one thousand receiving positions. 
To deposit individual mail pieces in the individual tiers in a synchronous 
manner, at least one synchronizing member is provided in the input module. 
The continuous conveyor of the input module includes a multi-loop path 
made up of a plurality of interconnected transporting sections with each 
section being approximately in a horizontal plane with the individual 
planes spaced apart in the vertical direction. The multiple loop-like 
transporting sections for the forked pallets is advantageous to provide 
the transfer of the mail pieces to the individual tiers of the transporter 
conveyor. 
To remove the mail pieces from the fork support or basket on the 
transporter conveyor, a removal device is provided which is also equipped 
with fork arms. The fork arms can take a mail piece from the fork baskets 
on the transporter conveyor and direct it into a collecting container in 
the output module 
Dividing the transporter conveyor into a plurality of vertically spaced 
tiers permits the formation of zones, each with approximately four tiers, 
which can be covered by a vertically movable extracting device, affording 
one extracting device for processing the mail in four tiers of one zone. 
The apparatus involving the present invention is coupled with an electronic 
data processing system which carries out all of the distributing and 
control operations. 
Such control operations range from the possible coding and detection of 
individual mail pieces to the positioning of the individual forked pallets 
on the input module conveyor, the transfer from the input module into the 
transporter conveyor and the subsequent removal or extraction from the 
transporter conveyor into a receiving container in the output module. The 
coding and distribution can lead to a further processing, possibly to a 
further pass through the apparatus for a more detailed sorting of the mail 
pieces. 
Control of the apparatus can be effected so that preliminary depositing is 
carried out during introduction onto the transporter conveyor whereby the 
individual extracting devices do not have to move over any distance in 
effecting a sorting process. The preliminary distribution can be performed 
so that a given destination is placed in a tier of the transporter 
conveyor. The extracting device can then be operated in one position. 
The following advantages can be obtained by using suitable software: a high 
average throughput, processing of peak loads by means of buffers, and a 
high availability by using parallel apparatus and particularly effecting 
exchangeability of the individual system elements by utilizing individual 
modules. The possibility of selecting the number of operational planes and 
the number of modules is particularly advantageous so that the system can 
be tailored for each application. Automatic load adaptation and 
frictionless operation can be achieved with corresponding software during 
outages of portions of the system. 
The various features of novelty which characterize the invention are 
pointed out with particularity in the claims annexed to and forming a part 
of this disclosure. For a better understanding of the invention, its 
operating advantages and specific objects attained by its use, reference 
should be had to the accompanying drawings and descriptive matter in which 
there are illustrated and described preferred embodiments of the invention 
.

DETAILED DESCRIPTION OF THE INVENTION 
The main parts of the apparatus 1 are illustrated in FIGS. 1 and 2. 
To sort mail pieces, not set forth in more detail, the mail pieces are 
delivered in pallets 2 and are placed in a receiving or separating station 
3, with two separating stations 3, 3' shown in FIG. 1. The mail pieces are 
moved from the separating station, described in more detail below, on to 
individual transport pallets 4 which are transported to a transporter 
conveyor 6 by an individual mail piece conveyor 5. 
As displayed in FIG. 2 transport conveyor 6 is a circulating continuous 
conveyor with a plurality of individual receptacles 7 for individual mail 
pieces. To provide synchronization between the transporter conveyor 6 and 
the individual mail piece conveyor 5, at least one synchronization unit 8 
is provided with the transfer operation between the two conveyors 
indicated in FIG. 1 by the arrow 9. 
As can be seen in FIG. 1, the continuous conveyor 6 of the transporter has 
a plurality of receptacle planes extending horizontally and spaced apart 
vertically with each plane equipped with a number of individual 
receptacles 7. The receptacle planes are arranged in two groups 10, 10' 
each containing four tiers of the receptacle planes. To provide transfer 
from the individual mail piece conveyor 5 into the transporter continuous 
conveyor 6 the conveyor 5 is formed with a plurality of horizontally 
arranged vertically spaced conveyor loops 11 so that the individual mail 
pieces can be aligned opposite each of the tiers of the receptacle groups 
so that the mail pieces can be transferred in a synchronized manner. 
To facilitate the description, the devices 3, 3' in the receiving or 
separating station 3, the pallets 4, the individual mail piece conveyor 5 
with the synchronization unit 8 and the transfer loops 11 of the conveyor 
are designated as an input module 12. In FIG. 2 a plurality of input 
modules 12 are shown arranged in parallel with one another. The input of 
the mail pieces into the apparatus is shown by the arrows for each of the 
input modules. At another location of the intermediate transporter there 
is a plurality of output modules 13, note FIG. 12, located adjacent to the 
transporter conveyor 6. The transporter conveyor 6 has a multiplicity of 
individual receptacles, there may be one thousand individual receptacles 
per conveyor. 
The output modules 13 receive the individual mail pieces located in the 
individual receptacles 7 in the transporter conveyor 6 and place them in 
containers 15 for the mail pieces. When the containers 15 are filled, they 
are carried by an output module conveyor 16 located at the lower end of 
each group of tiers 10, 10', shown in FIG. 2. Empty containers to receive 
mail pieces are also introduced to the apparatus by the same output module 
conveyors 16. The movement of the containers into and out of the output 
module is shown by the arrows 17 in FIG. 2. 
Details of the separating station 3 are displayed in FIGS. 3 and 4. A 
pallet 2, shown by the reference numeral 18 in FIG. 3, forms a container 
15 for mail pieces and is loaded with mail pieces of different sizes and 
thickness and is mounted on a vibrating table 19 and is maintained in a 
special angular position as indicated in FIGS. 3 and 4. One side of the 
vibrating table 19 is equipped with format baffle plates 20, note FIG. 4, 
offset in a stepwise manner for accepting mail pieces at different depths, 
note FIG. 4, and this arrangement has particular advantages for optical 
detection devices not shown in any detail. 
To remove the upper mail piece out of the container 15 it is lifted in an 
upward direction by an advancing means 21, not shown in greater detail, 
and a gripping device 22 is provided movable on the portal frame 23 in the 
direction of the double arrow 24. The gripping device 22 has a gripping 
plate 25 on a support 26 which can be moved in the direction of the double 
arrow 27 and can also be pivoted as indicated by the double arrow 28. The 
gripping plate 25 has a plurality of suction cups 29 on its underside and 
the gripping plate also has mechanical grippers 30 not shown in detail, at 
one end of the plate. 
Gripping device 22 works in the following manner: after automatic format 
detection of the upper mail piece, the support 26 with the gripping plate 
25 are moved over the mail piece with the activation of as many suction 
cups 29 as required to correspond to the size and weight of the letter or 
mail piece. Gripping device then moves the upper mail piece over a 
supporting and wiping mechanism 31 for completely gripping the mail piece 
by mechanical grippers 30. Accordingly, the suction cups 29 need only 
apply a slight output for the required lateral thrust. The mail piece is 
then placed on a carrying fork 32 forming a part of the transporting 
pallets 4 with the fork being pivotally movable around at least two 
separate axes. 
Transporting pallet 4 is set forth in more detail in FIG. 5. Transporting 
pallet 4 is also characterized as a forked pallet since it is equipped 
with the carrying fork 32 which, as mentioned above, is pivotally movable 
about at least two axes indicated in FIG. 5 by the double arrows 33, 34. 
Base 35 of the forked pallet is mounted on the input module conveyor 5. 
Carrying fork 32 can be pivoted out of the travelling direction, as shown 
by the arrow 36, in an outward direction by a corresponding control means, 
for example, for the purpose of coding, as indicated in FIG. 6. For coding 
the fork 32 is pivoted so that the mail piece is positioned in front of a 
coding station where it can be read. At the coding station, a person 
inputs the destination of the mail piece using a coding device 37 note 
FIG. 6. It should be noted that it is not necessary for the letter itself 
to be coded, since the coding information can be assigned directly to the 
forked pallets 4, 4' and to the other parts of the apparatus or system. 
The detection of the transported mail piece is possible by means of the 
individual transport. 
In FIG. 7 the transfer station cf the mail pieces from the forked pallets 4 
of the input module to the individual receptacles 7 in the transporter 
conveyor 6, is depicted. The individual receptacles 7 are also formed in a 
fork-like manner as indicated in FIG. 7. The speed of the forked pallets 
corresponds to that of the individual receptacles by means of the 
synchronization unit 8 in the input module. In the transfer operation, the 
fork 32 pivots downwardly with the mail piece 18 so that it moves through 
the forked basket 38 of the individual receptacles 7 with the first part 
of the pivoting operation being displayed by the circled portion 1 in FIG. 
7. The exact transfer is exhibited in FIG. 7 by the circled position 2 and 
with the further downward pivotal movement of the fork 32 the mail piece 
18 is deposited in the forked basket 38 as displayed by the circled 
position 3 in FIG. 7. 
In FIGS. 8 and 9 the transporter conveyor 6 located between the input 
module and the output module, is illustrated as a continuous conveyor with 
a plurality of tiers of individual receptacles 7 combined to form the tier 
units 10, 10'. In the plan view of FIG. 14 output module conveyor 16 is 
shown and located below the tier units 10, 10' in FIGS. 8 and 9. According 
to the height, length and filling density, it can be noted that 
transporter conveyor 6 can be equipped with a multiplicity of individual 
receptacle 7 from which a mail piece can be removed individually. An 
extracting device forming a part of the output module 13, is set forth in 
more detail in FIGS. 10 to 13. The output modules include vertically 
movable extraction devices 14 movable in the direction of the double 
arrows 39 in FIG. 10. A container 15 for mail pieces is assigned to each 
of the extracting devices 14. If a container is full, it is placed on the 
conveyor 16 and an empty conveyor is supplied to the extracting device. 
The extraction or removal of the mail pieces is explained briefly with 
reference to FIGS. 12 and 13: The extraction device 14 includes a forked 
gripper 40 secured to and extending outwardly from a crank gear 41. As 
mentioned above, the forked gripper is movable in the vertical direction. 
This feature of its movability means that the extracting operation is not 
performed in synchronization with the moving continuous conveyor 6 of the 
transporter, instead it is carried out in as short a time as required to 
swing through and empty a corresponding receptacle 7. The movement of the 
extracting device 41 relative to the receptacle 7 is indicated by the 
shaded portion 42 in FIG. 13. The mail piece in the forked basket 38 of 
the receptacle 7 is lifted by the forked gripper or fork 40 in a very 
rapid movement so that it remains positioned on the fork. The fork 40 then 
carries the mail piece upwardly and in a rotational movement deposits it 
against a displaceable rear wall 43 of the container 15 for the mail 
pieces. Rear wall 43 is displaceable in a synchronous manner in accordance 
with the filling state of the container 15. A stop or baffle plate 44 is 
provided at the end of the receptacle adjacent the extracting device 14 
and prevents mailing pieces from falling out of the front of the container 
and swivels in a reciprocating motion upwardly and then downwardly in a 
synchronous manner when the mail pieces are read. 
In FIG. 14 a plan view is shown of the output module conveyor 16 with empty 
position 45, empty containers 15 for mail pieces, and filled containers 
15' for mail pieces. Empty containers 15 are supplied to the conveyor 16 
along an inlet feed path 46. Full containers 15' are removed from the 
conveyor 16 along a removal path 47. The full containers may be introduced 
at the receiving or separating stations 3 for a further sorting and 
distribution operation. 
FIG. 15 illustrates a possible contruction of a container 15 for mail 
pieces. Front and rear sides 50 of the container can be plugged in, as 
indicated in dash-dot lines in different positions on a base plate 49 
containing a plurality of plug-in holes. Such an arrangement, as shown, 
frequently suffices for holding the mail pieces. 
As set forth in FIGS. 15A-15C, respectively, a container 15 can be enclosed 
with a shrinkage foil 51, with a cover 52 slipped over the container, or 
with a covering 53. Transporting cams and/or coding cams 54 can be 
provided along the side of the base plate 49. Additional cams 54 can be 
used as required. 
While specific embodiments of the invention have been shown and described 
in detail to illustrate the application of the inventive principles, it 
will be understood that the invention may be embodied otherwise without 
departing from such principles.