EP1093402A2

EP1093402A2 - Device and method for producing a complete stack

Info

Publication number: EP1093402A2
Application number: EP99944237A
Authority: EP
Inventors: Ottmar Kechel; Walter Rosenbaum; Josef Mok
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 1998-07-01
Filing date: 1999-07-01
Publication date: 2001-04-25
Anticipated expiration: 2019-07-01
Also published as: WO2000001496A2; DE19829484C1; EP1093402B1; WO2000001496A3; DE59902361D1; JP2002519196A

Abstract

The invention relates to a device and a method for producing a complete stack of flat items for sending, these items being provided with information for distribution, in a set order of distribution with given distribution stopping points. The complete stack is compiled from several stacks (31, 32, 33) of items which have been sorted in the same order of distribution. The inventive device comprises a stack-holder for each stack (31, 32, 33), separating devices for the stacks (31, 32, 33), each of which leads to a distribution information reader (13), intermediate storage elements, each with one or more storage steps (15, 16), a continuously driven transportation device with a transportation line (11, 12) for transporting the items (5) to a stacking device, said line being divided into equal sections. The items (5) for a particular distribution stopping point can only be transported onto the transportation device when all of the items (5) from the respectively preloaded stack holders for the previous distribution stopping points (according to the order of distribution) can be supposed to have passed the respective intermediate storage exit according to a predetermined degree of probability. The items can be loaded into the transport sections one above the other in accordance with the order of distribution.

Description

description

Device and method for generating an entire stack

The invention relates to a device and a method for generating an entire stack of flat mail items provided with distribution information in a predetermined distribution order from a plurality of stacks of mail items sorted in the same distribution order.

Particularly in the case of aisle sorting, increasingly pre-sorted stacks have to be combined to form an overall stack that is carried out by the deliverer in question. On the one hand, these pre-sorted stacks come from large customers, who use the sorting plans provided by the postal services to put uniform consignments such as magazines, magazines, advertising material in the correct order, and on the other hand from the postal service itself, using the appropriate sorting machines are available in certain time slices, thus creating multiple batches to be combined.

This combination of the pre-sorted stacks into an overall stack in the delivery order of the deliverer has hitherto been carried out manually, mostly by the delivery operator, mostly time-consuming.

If previously existing sorting machines were used, the advantage of the previous sorting in the order of distribution would be lost, since the pre-sorted stacks are entered one after the other, the pre-sorting being irrelevant.

The invention specified in independent claims 1 and 17 is therefore based on the object of a device and to create a method with which batches of mail items pre-sorted in a certain distribution sequence are to be automatically combined to form an overall stack in the same distribution sequence.

The invention enables a cost-effective and secure automatic consolidation of the pre-sorted batches of mail into an overall batch in the same distribution order.

Using the sorting of the individual stacks and the parallel loading of the means of transport that transports the mail items to the stacking point for summarization to form an entire stack, this entire stack is generated efficiently and quickly. The means of transport has a low-effort, continuously driven, rotating and sectioned transport line, with which no gaps between shipments can be created. On the one hand, when loading the consignment onto the transport line, it must be clear that only consignments for the same or a later distribution stop point may follow after each loaded consignment, and on the other hand, as few free sections as possible should result on the transport line for high throughput, a far-reaching one must be provided Knowledge of the composition of the individual stacks is available. Therefore, if this knowledge is not already available, it is necessary to look as far as necessary into the stack and to record the distribution information. This is achieved by temporarily storing the items in as many stages as necessary after reading the distribution information.

Be according to claim 17, the distribution information acquired in ^'the composition of the individual stacks to the ER, along with batch and / or program identifiers the total stack convincing device transmitted, so the necessary distribution information and sequences for all shipments are known and a multi-stage intermediate storage is not absolutely necessary for an optimal plan for loading the transport device.

Advantageous embodiments of the invention are specified in the subclaims.

The throughput can be further increased according to claim 2 by stacking mail items in the sections to the extent permitted.

For parallelization and for loading the transport line as quickly as possible, it is advantageous according to claim 3 to load shipments for the next but one distribution stop on the transport line if it is ensured that between the section with the last shipment of the current distribution stop and the first section for the Shipments from the distribution point after next fit all shipments at the next distribution stop.

In order to achieve a high level of utilization of the transport line, according to claim 4, shipments from the next distribution stop can already be stacked within the permissible total thickness within the permissible total thickness.

So that as few free sections as possible appear on the transport line, it is favorable to load the shipments of the distribution point to be loaded next into an empty section that is closest to the section containing the last mailings of the current distribution point. In a further advantageous embodiment, all shipments that can be loaded onto the transport strand at the same time are observed in parallel, while observing the distribution order. This also serves for the quick and compact loading of the transport line.

In order to minimize the number of free sections of the transport line, the shipments should be loaded into successive sections for one distribution stopping point, provided this is possible on the basis of the composition of the individual stacks.

It is also advantageous to begin the determination of the consignment to be loaded onto the transport route with the consignments from the stack receptacle closest to the stacking device, since these consignments have an effect on the loading processes from the stack receptacles in front of them.

In order to ensure safe loading of the mail items onto the transport line without stressing the mail items, it is advantageous according to claim 9 to adapt the loading speed to the transport speed and to adapt the loading times to the position of the sections.

In order to implement the buffer stores with little effort, they can be designed as a separately controlled transport route. According to claim 11, it is advantageous to provide thickness measuring devices for the mail items after the separating devices and before the intermediate stores, so that the maximum number of mail items that can be loaded into a section of the transport line can be determined while observing the maximum total thickness.

According to claim 12, the mail items are advantageously stacked and transported horizontally, which enables a low-cost implementation in terms of device technology. For simple and robust realization of the transport routes, these can be constructed according to claim 13 from endless conveyor belts guided over rollers.

In order to prevent the mail items from slipping on the conveyor belts during the start-stop movements during intermediate storage, it is advantageous according to claim 14 to press the mail items onto the conveyor belts by means of resilient pressure rollers. In this processing of the lying mail items, it is advantageous, according to claim 15, to include the batch receptacles in the separating devices and to separate them by subtracting the bottom mail item. According to claim 16, the stacking device advantageously has two stacking stations, the respective other stacking station being actuated when a defined filling level is reached. As a result, it is not necessary to stop the device to form the entire stack, since alternately a stacking point is unloaded and a stacking point is filled. The transmission of the distribution information of the individual stacks from the locations at which the information was ascertained to the device for generating an entire stack advantageously takes place via data networks.

The identifier of the distribution information and the shipments can contain an identification code and / or the identified and coded address information.

The invention is explained in more detail below in an exemplary embodiment. The drawing in FIG. 1 shows a schematic side view of the device according to the invention, FIGS. 2 and 3, the sorting sequence with 10 batches of mail items in sections in 12 time steps. As can be seen from FIG. 1, a continuously driven transport device transports mail lying horizontally from left to right into a stacking container 10, in which they are stacked one above the other in order to form an entire stack in a defined distribution sequence. The consignment 8 is moving from the transport device to the uppermost consignment 9 located in the stacking container 10. The transport device has a transport strand which consists of an endless conveyor belt 11 running around it. This conveyor belt 11 is divided into uniform sections by means of drivers 12. Shipments 5 are loaded into these sections, further shipments 7 also being transported one above the other in a section up to a fixed overall thickness. For loading the mail items 5 there are corresponding devices for each stack 31, 32, 33 sorted in the specified distribution order. Each stack 31, 32, 33 is placed in a stack receptacle, the mail items being in a lying position. The stack receptacles are arranged obliquely so that the mail items of the stack are aligned on a front stop wall 2. In a sequence to be explained below, the stacks 31, 32, 33 are separated by pulling off the bottommost mail item 3 of the stacks to a feed device 14. So that the bottom mailpiece can be pulled off, the front stop wall 2 has a gap 4 at the bottom through which the mailpieces 5 reach the feed device 14. A trigger device known per se is not shown in detail here. This can consist, for example, of trigger belts operating in the start-stop mode with high coefficients of friction and vacuum support, and with known retaining devices (wipers) to prevent double triggering. The feed Devices 14, which consist for example of endless conveyor belts, each transport the individual mail items 5 to distribution information readers 13, for example barcode readers. With this information, the shipments are assigned to the individual distribution stops. This is done in a control device, not shown. After the distribution information of the programs has been read, the programs 5 arrive at two-stage buffers. These consist of two transport lines 15, 16 arranged one behind the other - endless belts driven and guided by rollers. Each transport route 15, 16 can be controlled separately via the control device, so that the mail items 5 can, depending on the reading result, go directly into a specific section of the conveyor belt 11, or in the first and / or the second transport route 15, 16 as long as desired according to the distribution information and the distribution order can be buffered.

The mailings 5 are transported out of the second transport path 16 into a specific section of the moving conveyor belt 11 in such a way that the mailpieces 5 have approximately the speed of the conveyor belt 11 when they are handed over. This discharge movement is started so that the mail items 5 are deposited within the sections. The movements of the second transport route are therefore synchronized with the movement of the conveyor belt 11. So that the mail items 5 do not slip during intermediate storage and removal, they can be pressed onto the transport lines 15, 16 by means of spring-loaded rollers or belts. The drivers 12 and the machine geometry, including pressure rollers, are designed such that a plurality of mail items 5 can be stacked on top of one another in the sections of the conveyor belt 11 up to a predetermined total thickness. to In compliance with this condition, the thicknesses of the individual mail items 5 are measured by means of thickness sensors, for example rows of light barriers. These measurements must be carried out for each individual consignment if the individual stacks are inhomogeneous, ie consist of consignments of different thicknesses. If, on the other hand, consignments 5 from major customers are distributed, that is to say many consignments of the same type 5 in succession, and if these consignments 5 of the same type are loaded into a respective stack receptacle, it is sufficient to carry out the thickness measurement only for the respective first identical consignment 5.

The stacking device, not shown in more detail, located at the end of the transport device can be constructed, for example, from a chain which is guided over two large deflection rollers and which is made up of plates with the dimensions of the largest mailpieces and at distances from one another which are greater than the length of the largest mailpieces in the transport direction . The chain is driven in such a way that a shipment is always transferred to a plate. Two stacking containers are located between the deflection rollers below the chain parts moving in the transport direction. An up and down movable scraper is assigned to each stacking container. It is located at the rear end of the stacking container in the transport direction. If there is a shipment on a plate and this is to be stacked in the relevant stacking container, the scraper is moved downwards. The shipment bumps into it, the plate moves on and the shipment falls into the stacking container. In order to ensure a safe wiping, the plates have grooves into which tines of the fork-shaped wiper protrude. The two wipers are controlled so that one stacking container is filled and the other stacking container is changed in the meantime so that the machine run does not have to be interrupted. It is important for the throughput of the device that the mailpieces 5 are optimally transferred from the buffer store to the transport device which transports the mailpieces 5 to the stacking point, where the entire stack is formed. It is obvious that the decision as to whether a certain consignment is transported to the transport device depends on the content of the other batch receptacles. The more detailed the contents of all batch recordings with regard to the assignment of each mail item 5 to a distribution stop point are known, the more time-efficiently the mail items 5 can be loaded onto the transport device. If this knowledge of the previous sorting process for forming the individual stacks is known and has been transferred to the control device, then after the respective shipment 5 has been identified in the distribution information reader 13, the shipment only has to be buffered once. If this knowledge is not available a priori, it is necessary to "look" as far as possible into the individual stacks 31, 32, 33. In this example, a double intermediate storage was therefore chosen, ie the assignment of each stack 31, 32, 33 is known of the next two consignments 5 to the distribution stops, which means that a decision can be made early on about the transfer to the transport facility.

The individual transfer decision rules are explained below.

The first intermediate storage stage implemented as a transport route 15 behind the distribution information reader 13 is called buffer A, and the following intermediate storage stage implemented as a transport route 16, from which the mail items 5 reach the conveyor belt 11, buffer B. The determination of the transfer decisions is started for the consignments of the batch pickup that are closest to the stacking device, since these consignments have an effect on the loading processes from the batch pickups in front of them. In general, mail items 5 for a specific distribution stop point are only loaded into a section of the conveyor belt 11 when all mail items from the stack receptacles upstream in the transport direction for the distribution stop points previous according to the distribution order have left the respective intermediate stores, whereby mail items 5 up to one have been adhered to in the distribution order specified total thickness can be loaded into the sections of the conveyor belt 11. Shipments 5 for the same distribution stopping point can thus be loaded onto one another, as well as shipments of the next distribution stopping point in the distribution sequence for the last shipment of a specific distribution stopping point.

At the beginning of the sorting process, all mail items 5 for the first distribution stop point in the distribution sequence are loaded in parallel from the buffers B onto the still empty conveyor belt 11. If possible, the parallel loading is carried out during the entire sorting process.

In order to avoid empty sections of the conveyor belt 11, shipments 5 for a specific distribution stop point are loaded, if possible, into a section which follows a section with shipments 5 for the same distribution stop point. Furthermore, under appropriate conditions, the mail items 5 for the distribution point to be loaded next on the conveyor belt 11 are transported into a section which is closest to the section containing the last mail items of the previous distribution point. Is it clear from the information about the shipments in the batch recordings how many sections of the conveyor belt 11 for the mail fertilization of the distribution point to be loaded next is required, mail items 5 for the distribution point next to the next in the distribution sequence can also be loaded into a section lying in front of it.

If several consignments are to be loaded onto the conveyor belt 11 for a distribution stopping point, the consignments are prioritized with regard to the sequence. The prioritization takes place in such a way that the highest possible throughput during sorting results.

In the following explanations, a device with 10 stack receptacles and associated buffers A and B is agreed.

The mail items for the distribution stopping point 1 are first to be loaded onto the conveyor belt 11 and are stacked at the bottom in the stacking container 10, the mail items for the distribution stopping point with the highest number are loaded last and stacked at the top.

In the diagrams, the first line shows the number of the batch pickup, the numbers in the second line indicate the distribution breakpoints of the consignment located in buffer A for the respective batch pickup, the numbers in the third line the distribution stoppoints of those in buffer B for the respective batch pickup Consignment, the numbers in the fourth line the contents of the sections of the conveyor belt 11 currently located at the outputs of the buffers B. Here, x means empty and, for example, 3; 3; 2 means that in this section from top to bottom one shipment for distribution stop 2 and two shipments for distribution stop 3 were loaded one above the other. The conveyor belt 11 is moved from left to right. The prioritization of the shipments is based on following table explained. This table shows a ^'' snapshot 'during the sorting process.

Stacking 10

Buffer A 7 8 9 7 9 6 11 9 8 5 buffer B 6 7 7 6 7 6 10 5 4 4 conveyor belt X 5; 5 4 4; 4 4;: 4 2; 2 2

5 4 2

Table 1

The shipment for the distribution stop 5 in the buffer A 10 (buffer A for the stack holder 10) prevents the shipment for the distribution stop 6 in the buffer B1 from being loaded onto the conveyor belt 11. Only when there is a shipment in the buffer A10 for a distribution breakpoint ≥6 can the shipment be loaded from the buffer B1.

So that the shipment for the distribution stop 6 from the buffer B1 can be loaded onto the conveyor belt 11 as early as possible to increase the throughput, the transfer of the shipment for the distribution stop 4 from the buffer BIO to the conveyor belt 11 has the highest priority over the other shipments for the distribution breakpoint 4 in the buffers B. This transfer can be implemented since there is still space for the shipment from the BIO buffer in the current section 7 of the conveyor belt 11. Therefore, the mail item for distribution stop 4 in buffer B9 is not combined with the mail items for the same distribution stop point under buffer B7, but with the mail item under buffer B5. As a result, the shipment for the Distribution stop 6 in the buffer B1 two steps earlier to be loaded onto the conveyor belt.

On the basis of the table shown in FIG. 2, a sorting process is carried out, for example, in time steps as explained. Here means

B2 Buffer B for stacking 2 A4 Buffer A for stacking 4

C7 at the time in question under the buffer B of the stack holder 7 section of the conveyor belt

The arrow points to the next shipment 3 to be loaded onto the conveyor belt; 3; 2 the lowest shipment is for distribution point 2, above it are two shipments for distribution point 3 3p8 shipment for distribution point 3 and priority 8, i.e. the shipment in B8 must be transferred as early as possible. EC transfer condition (eject condition)

The stack lines - stack holder and associated buffer - with the highest priority are printed in bold and oblique. The consignments are stacked in the total stack from bottom to top with increasing distribution stop number. As can be seen from previous explanations, the entire stack can be formed as quickly and without errors as complete information as possible about the composition of the stack in the stack receptacles with regard to the distribution breakpoints is available. This means that the number of memory levels in the buffers should be as large as possible. Since this in turn would greatly enlarge and increase the cost of the machine, it is advantageous in terms of the number of Storage levels of the buffer and the machine throughput to compromise. For this reason, the composition of the stacks is statistically evaluated over a longer period. If, on the basis of the statistical data, it is unlikely that certain batch compositions will occur, consignments for a specific distribution breakpoint can be loaded onto the transport device, taking into account this assumption, although it is not 100% certain that there is not yet a consignment in a batch for a previous batch distribution point to be filed. This variant can be useful if, for example, the throughput can be increased by 20% with an error rate that is only 0.5% higher. When the individual batches for the batch receptacles are formed, the information regarding the distribution breakpoints assigned to the individual shipments is ascertained or is already available during the formation. If this data is then transmitted to the device for forming the entire stack, for example via data networks, then the entire stack can be formed quickly with little expenditure on equipment, based on the knowledge of the composition of the individual stacks - only a one-step intermediate storage is necessary. So that the individual shipments can be assigned to the transmitted distribution breakpoints, at least every batch must be provided with an identification code. When the data is transferred, the batch identification is also transferred. Since the order of the shipments is retained in the stack, identification of the individual shipments is not absolutely necessary, but can be done for additional security. The individual consignment can be identified by a consecutive ID number in barcode form or by the distribution information that is recognized and applied as a barcode.

Claims

claims

1. Device for generating a total stack of flat mail items provided with distribution information in a specific distribution order with given distribution stops from several stacks (31, 32, 33) of mail items sorted in the same distribution order, consisting of

- one stack holder for each stack (31,32,33)

controllable separating devices for separating the stacks of mail items (31, 32, 33) from the stack receptacles into one feed device (14) each for a distribution information reader (13),

- the mail items (5) from the respective distribution information readers (13), with at least two storage levels (15, 16),

a continuously driven transport device with a circulating transport line divided into uniform sections for receiving one or more mail items (5) from the intermediate stores up to a specified total thickness and for further transport of the mail items (5) to a stacking device for the entire stack,

a control device for controlling the separating devices, feed devices, distribution information readers, intermediate stores,

- That the mail items (5) can only be transported from a buffer to the transport device for a specific distribution stop when all the mail items from the stack recordings upstream in the transport direction for the distribution points previous according to the distribution sequence have passed the respective buffer output with an agreed probability.

2. Apparatus according to claim 1, wherein the control device is designed so that mail items in compliance with the partial order up to the specified total thickness can be loaded into the sections of the transport device.

3. Apparatus according to claim 1 or 2, wherein the control device is designed such that when the last shipment of a respective distribution stop is in a certain section of the transport device, at least one shipment of the next but one distribution stop in the distribution order is in a section of the transport device is loaded when between this section and the section with the last shipment of the respective distribution stop all shipments for the next distribution stop in the distribution sequence can be loaded.

4. Device according to one of claims 2 to 3, wherein the control device is designed so that on the last shipment / shipments of a certain distribution breakpoint up to the specified total thickness, shipments of the next distribution breakpoint in the distribution order are stackable.

5. Device according to one of claims 1 to 4, wherein the control device is designed such that the shipments of the next to be loaded onto the transport device distribution stop in an empty, the section containing the last shipments of the previous distribution point closest to the transport device loadable are.

6. Apparatus according to claim 1 or 2, wherein the control device is designed such that all mail items that can be loaded simultaneously from the intermediate stores are loaded in parallel onto the transport device.

7. The device according to claim 1 or 2, wherein the control device is designed such that the mail items can be loaded for one distribution stopping point into sections of the transport device lying one behind the other.

8. The device according to claim 1, wherein the control device is designed such that, in the case of newly filled stack receptacles, the determination of the shipments to be loaded onto the transport device begins with the consignments of the stack receptacle closest to the stacking device for the entire stack.

9. The device according to claim 1 or 2, wherein for the correct loading of the mail items from the intermediate stores into the sections of the transport device, the loading times are matched to the respective position of the sections and the loading speed of the mail items corresponds approximately to the transport speed of the transport device.

10. The apparatus of claim 1 or 9, wherein the intermediate storage each consist of one or more consecutively arranged transport routes (15, 16) which can be controlled separately in start-stop operation.

11. The device according to any one of claims 1 to 10, wherein there are thickness measuring devices for the mailpieces after the separating devices and before the buffers.

12. The device according to one of claims 1 to 11, wherein the mail items are stackable and transportable horizontally.

13. The apparatus of claim 10 and 12, wherein the transport routes (15,16) consist of endless conveyor belts guided over rollers.

14. The apparatus according to claim 13, wherein there are non-driven pressure rollers or belts which are movably mounted above the conveyor belts and are pressed by spring force against the conveyor belts.

15. The apparatus of claim 1 and 12, wherein the stack receptacles are part of the separating devices and the stack (31,32,33) can be separated by subtracting the lowest mail items (3).

16. The apparatus of claim 1, wherein the stacking device for the entire stack has two approachable stacking points, the other stacking point being in use when a defined filling level is reached.

17. A method for generating a total stack of flat mail items provided with distribution information in the form of addresses in a specific distribution order with given distribution breakpoints from several stacks (31, 32, 33) of mail items sorted in the same distribution order, the batches and / or the individual mail items having a Are provided with the steps:

Transfer the distribution information of the mail items determined during the sorting of the individual mail batches with these identifiers to a device for generating an entire stack, consisting of stack receptacles, separating devices for the mail items in the batch receptacles, distribution information and ID reading devices, and subsequent one-stage intermediate stores from which the mail items are stored Transport device with a rotating, continuously driven transport line, which is divided into uniform sections and which feeds the items to a stacking device for the entire stack, is loaded. - Creation of the transfer plan for loading the transport line by evaluating the transmitted address information of all shipments assigned to the distribution stops. Reading the identifiers of the stacks and / or the individual consignments and formation of the entire stack using the transfer plan for loading the transport line.

18. The method according to claim 17, wherein the identifying distribution information is transmitted via data networks.

19. The method of claim 17 or 18, wherein the identifier contains an identification code.

20. The method according to any one of claims 17 to 19, wherein the identifier of the mailings contains the identified and coded address information.