EP1836006A1

EP1836006A1 - Conveyor/sorter apparatus and method

Info

Publication number: EP1836006A1
Application number: EP05803985A
Authority: EP
Inventors: Uffe Lykkegaard
Original assignee: FKI Logistex AS
Current assignee: FKI Logistex AS
Priority date: 2004-11-22
Filing date: 2005-11-22
Publication date: 2007-09-26
Also published as: JP2008520518A; WO2006053570A1

Abstract

The invention relates to the field of sorting machines. The present invention relates to a sorter (1) for sorting articles such as CDs, videos, books, letters and/or flats and even mail parcels and other types of articles. In order e.g. to provide an improved relation between sorting capacity, sorting level and/or floor space the invention discloses in one aspect a conveyor system for conveying articles, comprising an endless track assembly (10a, 10b), a plurality of cartridges (15) for receiving articles and for discharging received articles there from, where the cartridges is supported from the track assembly and movable about a conveying path defined by the track assembly, and the conveyor system furthermore comprises a plurality of destination buffers (13, 14, 15, 16) for receiving articles being discharged from the cartridges (5), wherein the destination buffers (14) is positioned at a level below the cartridges and being movable transverse to said conveying path between two or more discharge positions.

Description

CONVEYOR/SORTER APPARATUS AND METHOD

FIELD OF THE INVENTION

The invention relates to the field of sorting machines. The present invention relates to a sorter for sorting articles such as CDs, videos, books, letters and/or flats and even mail parcels and other types of articles. In particular, the present invention relates to sorting articles of a relatively light weight such as, e.g., of a maximum weight of about 8 kg, in particular a maximum weight of about 5 kg. It will although be understood that the principles of the invention can be utilised also in connection with articles of a higher weight than about 8 kg. In particular, the invention relates to a sorter that allows a high degree of adaptability to requirements or constraints with respect to the space it can occupy.

BACKGROUND OFTHE INVENTION

Sorters for sorting of articles such as CDs, videos, books, letters and/or flats and/or bundles and other relatively light articles should be designed so that they can relatively easily be installed and operated under widely varying space conditions. Furthermore, it is of outmost importance that e.g. a predetermined sorting capacity, measured in articles per hour, and e.g. a predetermined sorting level, measured in a number of sorting destinations, can be achieved at the minimum space occupied by the sorting system.

SUMMARY OF THE INVENTION

The present invention relates to such sorters that are highly flexible with respect to their installation and operation and which permit the sorter units thereof to follow paths in any desired direction. The present invention relates to sorters which can be installed and operated in a space comprising more than one floor and/or on walls; in which a feeding station can be installed directly above or directly under a discharge station, and/or feeding stations or discharge stations can be installed directly above each other; and which can be made economically and yet deliver a highly efficient operation.

In the present invention, the articles to be sorted are mainly positioned with their smallest dimension extending substantially in a travelling direction of the articles carried by the sorter.

By positioning the articles with the smallest dimension of the articles extending in a travelling direction of the articles on the sorter, a higher sorting capacity is achieved along with a decreased need for space. A higher capacity and a decreased need for space is achieved when compared e.g. to a sorting capacity and a need for space when positioning the articles with the smallest dimension of the articles extending in a direction perpendicular to the travelling direction of the articles on the sorter. A sorter of the type where the smallest dimension of the articles is extending in a direction perpendicular to the travelling direction of the articles on the sorter is described in the European patent EP 1 044 148.

Although there are differences between the sorting system described in EP 1 044 148, and the present invention, the flexibility of the endless sorter track and other characteristics disclosed in EP 1 044 148, may be used with the present invention. Therefore, EP 1 044 148 is incorporated herein by way of reference.

An improved solution is achieved by positioning the articles with their smallest dimension extending in the travelling direction of the articles on the sorter, compared with the solution disclosed in EP 1 044 148. But still it has been found, that present sorting systems where the articles are travelling with their smallest dimension extending in the direction of travel, has certain disadvantages. These disadvantages may in particular be present when e.g. only very limited floor space is present and in particular, when present sorting systems further must provide a certain predetermined sorting capacity, measured in articles per hour, and/or e.g. a predetermined sorting level, measured in a number of sorting destinations.

It is therefore one object of the present invention to provide a sorting system with improved possibilities for installation on limited space compared to the present systems while still being easy maintainable, very reliable and providing high sorting capacity and a high sorting level.

The object of the invention is obtained by the invention according to the description of the present invention and the appended claims according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of sorting system according to an embodiment of the present invention.

Fig. 2 is a perspective view of a portion of the sorter system according to an embodiment of the present invention, seen from a position outside a sorter loop. Fig. 3 is a perspective view of a portion of the sorter system according to an embodiment of the present invention, seen from a position inside the sorter loop. Fig. 4 is a perspective view of a portion of the sorter system according to an embodiment of the present invention, seen from the outside of the sorter loop and perpendicular to a main track.

Fig. 5 is a perspective view of a curve of a main sorter track of a portion of the sorter system according to an embodiment of the present invention, seen from the inside of the sorter loop.

Fig. 6 is a perspective view of a part of the main track showing e.g. cartridges supported by the main track.

Fig. 7 shows two perspective views seen from opposite sites of a carriage assembly according to an embodiment of the present invention.

Fig. 8 is a perspective view of e.g. a cartridge according to an embodiment of the present invention.

Fig. 9 shows a drive assembly according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to sorter systems for conveying and/or sorting articles, as well as methods for conveying and/or sorting articles. While the present invention is not so limited, the sorter systems disclosed herein are particularly suitable for use in conveying and sorting postal articles such as letters, flats, and similarly-sized postal articles. ("Flats" are larger, flat mail pieces such as large envelopes, magazines, catalogs, etc.). For example, the sorter systems of the present invention may be used to sort postal articles into a single bundle of articles for each delivery point (e.g., a bundle of letters and flats for each mailing address). This bundle may include both letters and flats, as the sorter systems of the present invention may be configured to merge all of these items into a single bundle (e.g., utilizing cartridges which accommodate two or more distinct sizes of articles such as letters and flats). The result is that the carrier is provided with a single bundle of "mixed" mail for each delivery point. The sorter systems of the present invention are also modular in nature, particularly the main track assembly (e.g. a monorail assembly) which may be assembled in any of a variety of configurations. Also, the sorter systems of the present invention decrease the use of space, in that the transport path may include small radius curves, multiple levels, and even changes in elevation. The main track assembly (e.g. a monorail) may be similar or identical in construction to the various embodiments described in European Patent EP 1 044 148, which is incorporated herein by way of reference. One of the principal distinctions between the systems of the present invention and those described in EP 1 044 148 is that, in EP 1 044 148, the conveyor units (identified by reference numeral 1 therein) employ a "cross-belt" design for discharging articles to either side of the conveying unit. In the present invention, on the other hand, cartridges for receiving and discharging the sorted articles are provided. In particular, the present invention provides conveyor systems for conveying and/or sorting articles wherein the articles are inserted into a plurality of cartridges movingly supported by a main track assembly. In the described embodiments of the invention, the articles are preferably positioned within the cartridges with the smallest dimension of the articles extending in a travelling direction of the articles on the sorter. The cartridges are supported by the track assembly such that the cartridges will travel along a transport (or sorting) path defined by the course of the track assembly.

In an exemplary embodiment of the invention the cartridges are fixed in the transverse direction with respect to the conveyor path. In the embodiment, a destination buffer configured as a chute is sliding in a transverse direction with respect to the conveyor path. In the embodiment, the chutes with a sliding destination buffer may be provided along with one or more chutes having a destination buffer being fixed.

Fig. 1 is a perspective view of an exemplary conveyor/sorting system 1 according to one embodiment of the present invention. It should be pointed out that the system depicted in Fig. 1 is a simplified version, as a typical installation may often employ a considerably longer main track assembly 2 having multiple sorter legs, one or more separate induction legs and even multiple levels. The exemplary system depicted in Fig. 1 includes main track assembly 2 in the form of an endless loop. Main track assembly 2 may be assembled, for example, from straight sections 8a and 8b and curved section 9 assembled in an end-to-end fashion in order to provide the endless loop (as further detailed in EP 1 044 148). A plurality of cartridges 5 are movingly supported by track assembly 2 such that cartridges 5 may travel in serial fashion along the path defined by the course of track assembly 2 (in a counter clockwise manner in the exemplary embodiment shown in Fig. 1).

In Fig. 1, main track assembly 2 includes a pair of parallel, spaced-apart straight legs (or sorter legs) 8a and 8b, and a pair of curves 9 connecting adjacent ends of the two straight legs 8a and 8b. The straight leg 8b of main track assembly 2 in Fig. 1 also includes an induction section with one induction or feeder 3 and another induction or feeder 4 as shown.

In the embodiment of Fig. 1, articles to be conveyed and/or sorted are inserted into cartridges 5 at inductions 3 and 4. Only one induction may be provided, as well as more than two inductions. Furthermore, also a second induction area, not shown, may be provided in order to improve the capacity of the system. Articles may be inserted into cartridges 5 by hand, or by means of a suitable feed/insertion device. The system of Fig. 1 is particularly suited for the conveying and sorting of mail, such as letters and flats. Thus, the exemplary embodiment of Fig. 1 includes a feeder 4 which is adapted to individually insert letters from a stack into the cartridges 5 at an induction section. The exemplary embodiment in Fig. 1 also includes a feeder 3 which is adapted to individually insert flats from a stack into the cartridges 5. Feeders known to those skilled in the art may be used for this purpose.

In the embodiment of the invention, according to Fig. 1, chutes 6 are provided along the main track. The chutes 6 will be described in detail with reference to the following figures. Two conveyors 10a and 10b (e.g. flighted or cleated conveyors) are located beneath the straight leg (or sorter leg) 8a of main track assembly 2. In general, the conveyor 10b is aligned with main track assembly 2 such that a centerline of the conveyor 10b is situated directly beneath and aligned with the centerline of main track assembly 2. Furthermore, when a cartridge 5 is located at a discharge position, the cartridge 5 will be located directly above, aligned with the conveyor 10b. As further described herein, each cartridge 40 includes one or more "bomb bay" style doors through which articles may be discharged directly beneath the cartridge. Therefore, by aligning a conveyor and/or other suitable receptacles beneath the discharge position of the cartridges along a sorter leg, articles within the cartridges may be selectively discharged into (or onto) the conveyor and/or into the receptacle.

In the embodiment shown in Fig. 1, a series of bins 11a and lib are located on conveyors 10a and 10b for receiving articles discharged from the cartridges 5. Conveyors 10a and 10b may also be configured to ensure that the bins are aligned on the conveyor in a predetermined fashion in order to ensure that the articles are deposited into the appropriate bin. Alternatively, articles may be deposited directly onto the upper surface of the conveyors, and therefore the conveyors may include discrete individually delimited zones (see Fig. 3) for receiving articles discharged from the cartridges.

As further described herein, a series of chutes 6 and 12 and/or buffers (also see Fig. 2) may be provided between cartridges 5 and conveyors 10a and 10b. The chutes with or without buffers may be provided in order to guide discharged articles onto the conveyor or into a receptacle (e.g., a bin, a tub or a tote) positioned on the conveyor. Chutes 6 and 12 and/or buffers may also act as a destination buffer for accumulating articles discharged from the cartridges, and later depositing accumulated articles into a receptacle on the conveyor there-beneath or onto the conveyor itself. By way of example, and with reference to Fig. 1, postal articles for a single postal carrier may be inserted into cartridges 5 traveling along the conveyor path (e.g. using one or more feed devices 3 or 4 or similar apparatus). The control system will designate a receptacle (e.g. a bin 11) on one of the conveyors 10a and 10b for receiving all of the postal articles for a particular delivery destination (e.g., a single mailing address such as the street address of a house). Subsequent to the induction section, as the cartridges continue to proceed about the conveying path in order to discharge postal articles into the appropriate bins or destination buffers. Since each cartridge may have multiple article compartments as further described herein, compartments acting as pockets of the cartridge for the articles need not be emptied at one destination only, but e.g. separately opened at three different destinations. In addition, depending on the quantity of articles being sorted, the cartridges may make multiple passes around the conveying path loop until the entire set of postal articles has been sorted. If destination bins are being employed, once all of the postal articles for a designated bin have been deposited into the destination buffer, the buffer will discharge the sorted articles into the designated bin there-beneath. Thereafter, the bins may be removed, such as by advancing the bins along conveyors 10a and 10b to further processing and/or to the postal carrier for delivery.

Fig. 2 shows a part of the sorter system according to an embodiment of the present invention, seen from a position outside a sorter loop. Figure 2 shows the main track 2, which may be supported from the floor or hanging from a ceiling, with a number of cartridges 5. The centreline of the main track assembly is extending above a centreline of the flighted conveyor 10b. Figure 2 shows two types of chute assemblies, a chute assembly 6 with a fixed secondary destination buffer 13 and a chute assembly 12 with a displaceable secondary destination buffer 14. The word "fixed" used in relation to the buffer(s) means non-moveable in a transverse direction with respect to the travelling direction of the articles on the sorter.

The chute assembly 6 is further provided with a fixed primary destination buffer 15. The fixed primary destination buffer 15 is positioned adjacent to the cartridges running on the main track 2. The chute 6 is also provided with a fixed secondary destination buffer 13. The secondary destination buffer 13 is positioned adjacent to and below the primary destination buffer 15.

The chute assembly 12 is further provided with a fixed primary destination buffer 16. The fixed primary buffer 16 is positioned adjacent the cartridges running on the main track 2. The chute 12 is provided with a displaceable secondary destination buffer 14. The sliding secondary destination buffer 14 is supported from a support rail 21 extending in a transverse direction with respect to the travelling direction of the articles on the sorter. By suitable powering means, a movement of the sliding destination buffer 14, between a first destination position 22 and a second destination position 23 of the sliding destination buffer 14 can be provided. The destination positions 22 and 23 are positions along a direction transverse to the travelling direction of the articles on the sorter. The positions 22 and 23 are provided so as to enable discharging of articles from the sliding secondary destination buffer 14 to a trailing bin 20 positioned on the flighted conveyor 10b and to a leading bin 19 positioned on the flighted conveyor 10a, respectively.

The primary destination buffer and the secondary destination buffer of both the chute 6 with a fixed secondary destination buffer and of the chute 12 with a sliding secondary destination buffer, are each provided with a primary rest 17 and a secondary rest 18. The rests 17 and 18 may open and close, in dependence of predetermined signals from the control system of the sorting system, the control system being operated depending on the operation of the buffer and the sorting system. One or both of the rests may also stay open during operation depending on the operation wanted by the buffers and the system.

The position of the chute 6 and the chute 12, relative to the position of the bin 19 and the bin 20 enables for transfer of articles discharged from the cartridges 5 to both the bin 19 and the bin 20.

In operation, the system may, according to an embodiment of the invention, operate as the following example explains.

A primary and secondary rest of both the chute 6 and the chute 12 may initially be closed. When articles are discharged form a cartridge and a filling level of the primary destination buffer 16 of the chute 12 is reached, and/or when the articles for a given final street address are discharged to the buffer 16, the following may be provided:

The sliding secondary destination buffer 14 may be in the first position 22 or may at this moment be transferred to the first position 22. When the displaceable secondary destination buffer 14 is in the first position 22, the rest 17b may be opened and the articles will due to gravity flow into the below situated displaceable secondary buffer 14 until stopped by the rest 18b. The rest 18b of the displaceable secondary destination buffer 14 may then open and the articles may flow into the receptacle or the trailing bin 20. In an alternative employment, the secondary rest 18b is already open and the articles flows directly from the cartridge into the bin 20 along both the primary buffer bin and the secondary buffer bin. In even an alternative employment, the rest 18b is closed, as initially described, and the displaceable secondary destination buffer 14 slides to the second destination 23. When having reached the second destination 23, the rest 18b opens and the articles flow into the leading bin 19.

The primary buffer and the secondary buffer of both the chute 12 with a fixed secondary buffer and of the chute 12 with a displaceable secondary buffer may be provided with sides such as shown at 26. Still further, support rails 21 may be provided with guides for guiding the articles discharged along the secondary buffer bin 14 to land in the destination 19.

Power for opening and closing the rests may be provided by e.g. an electrical motor (not shown) and e.g. levering arms (not shown) connected to the rest. The electrical motor may, for the displaceable secondary rest 18b, be displaceable together with the displaceable secondary destination buffer 14. The electrical motor may, for the fixed primary rest 18b, may e.g. be fixed within the support 24 of the fixed secondary buffer. Power for the opening and closing movement of the rests may e.g. also be provided by one or more solenoids positioned on the rest or on the chute. The one or more solenoids may then activate a closing or an opening of the rest. This may be provided by a levering arm connected to the solenoid and engaging or disengaging with a common opening and closing movement of a moving member extending and positioned along the rests at positions 22 and 23.

The opening and closing of the destination buffers may additionally or alternatively be provided due to a level of filling of the destination buffer in question. The level of filling of one or more or all of the primary destination buffers and secondary destination buffers 13- 16 may be provided as follows:

The level may be detected by a photo electric cell (PEC) provided at the one or more buffers at a certain level above the rest of the buffer and/or at the top of the buffer such as known to those skilled in the art. The level of filling in the buffer may also or alternatively be acknowledged by the control system due to a detection of at least one dimension of the article at the feeder and/or even by detection of the volume and/or detection of the weight of one or more articles. Knowing the destination for each article, the dimensions and/or other data relating to the articles may then be added for a given destination and hereby the filling level may be provided.

A sliding movement of the displaceable secondary destination buffer 14 of the chute 12 assembly may e.g. be provided by an electrical motor (not shown) provided for moving of the displaceable secondary buffer sliding along a support rail 21. Alternatively to the displaceable destination buffer being displaceable by sliding along the rail 21 the following solution, which is not shown in the figures, may be provided. A conveyor belt having a length traverse to the conveyor path as the rail 21 may be provided at e.g. every second destination. The conveyor belt is preferably tilted in an angle in the conveyor direction similar to the angle of the displaceable destination buffer 14. The conveyor belt may then be operated as follows. When e.g. having received a number of articles on a part of the conveyor belt situated at the first position 22, while a rest is closed, the conveyor belt is driven a certain distance in order to displace the articles to e.g. the second position 23. At the second position the rest is opened and the articles may e.g. fall into a bin positioned below the second position. Hereby an alternative to the example of the sliding destination buffer as shown in the figures is provided.

The system may be operated such as to discharge the articles to the discrete delimited sections or zones of the flighted conveyors 10a and 10b without the bin 19 and/or 20 placed on the conveyors. During such an operation, the conveyors 10a and 10b may be lifted to a level of height decreasing the distance from a lower part of the rest and to the surface of the conveyors 10a and 10b.

Fig. 3 is a perspective view of a part of the sorter system according to an embodiment of the present invention, seen from a position inside the sorter loop. The part of the sorter is the same as the part shown and described in fig. 2. In particular, fig. 3 shows the main track 2 supported by the floor by a track support 27. Track support may also be adapted such as to support the support rail 21 for the cartridges and the support 24 for the chutes 12 and 6, respectively. The figure shows five sets of chutes, each set comprising a chute 6 and a chute 12. The figure shows the primary destination buffers 15 and 16 of the chute 6 and the chute 12 together with the displaceable secondary destination buffer 14.

One possible effect of the displaceable secondary destination buffers is that two destinations are within reach from one discharge position. Another possible effect of the chute configuration is that when the displaceable secondary buffer is not collecting articles discharged from the cartridges, the fixed primary destination buffer of the chute 12 may still be receiving articles to be discharged at this particular destination. And if the primary destination buffer of the chute 12 is also not collecting articles discharged from the cartridges, e.g. due to a maximum filling level of the primary destination buffer having been reached, the destination within reach by the chute 6 may still be open. Still further, when providing each chute 6 with the displaceable secondary buffer of the chute 12 a still further degree of flexibility is provided in the system. The degree of flexibility wanted is a question of the operation wanted compared with a cost of providing the flexibility. Another possible effect of providing a displaceable secondary destination buffer, e.g. in stead of a cartridge adapted for moving between transverse positions with respect to the conveying direction of the carriers, may be that no electrical motor drive means are present on each carrier. Hereby the reliability of the sorting system is enhanced compared to the solution with a moveable cartridge. Still further, the amount of energy, which must be transferred to the chain of cartridges, is relative low if for example solenoids are provided compared to a solution with moving cartridges. However, the disadvantages described for the moving cartridge solution are not at all comparable with the potential benefits of a moving cartridge solution compared to known solutions having neither movable cartridges nor displaceable secondary buffers.

One of the benefits or possible effects of the moving cartridge solution may e.g. be providing the possibility of reaching a double amount of destinations by means of only one cartridge. Reaching the double amount of destinations at the chute pitch described and without increasing the length of the sorter track, may e.g. be achieved by a combination of the moving cartridge solution with the displaceable buffer solution.

Providing the buffers and/or providing the possibility of reaching the highest number of destinations possible at a given sorter leg also has a possible effect of decreasing to a minimum the number of re-circulating articles generated by the sorter system. A re- circulating article is an article that is inserted into a compartment of a cartridge and e.g. due to the designated final position not being open for discharge, the article is still in the compartment after having passed the one or more chutes allocated for discharging of the article. Re-circulating articles are decreasing the capacity of the sorting system.

Fig. 4 shows the main track 2 and a portion of the embodiment of the invention as described in figures 1-3 with the cartridges 5 each supported by a first suspension arm 33 and in combination with other elements providing a carrier assembly as indicated at 32. In the embodiment shown, a carrier pitch 28, a chute pitch 29, a buffer bin pitch 30 and an offset distance 31 between the trailing bin 20 and the leading bin 19 is provided. The offset distance is shown to be substantially equal to the chute pitch 29. In the embodiment shown, the chute pitch 29 is between 0,1m and 3m, preferable between 0,1m and 0,5m, the carrier pitch is between 0,1m and 3m, preferable between 0,1m and 0,5m and the distance 30 is substantially double the chute pitch 29. By the described configuration and chutes, articles from one cartridge may be discharged to two bins 19 and 20. This configuration provides a decreased need for footprint due to two bins 19 and 20, and not only one, being reachable from one fixed cartridge 5 of the sorting system. Rg. 5 shows a sorter curve 9 of the main track 2. The travelling direction of the carriers running supported by the main track is indicated at the arrow 7. It is shown that the carrier pitch is the same along a straight part of the track as along the curve 9.

Figures 6 - 8 depict an exemplary embodiment of a cartridge 5 according to aspects of the present invention. Rectangular cartridge 5 is particularly suited for receiving and discharging postal items (including both letters and flats) and articles of similar size and shape. However, the present invention is not limited to systems for conveying and/or sorting postal items, as it may be used for a variety of other articles.

In the embodiment shown in Figs. 6-8, cartridge 5 includes three compartments (or pockets, which the compartments also may be called) configured for receiving postal items. Of course this is merely exemplary, as the cartridge may include a single compartment, or any number of compartments, as desired. As best seen in Fig. 7, cartridge 5 includes a first compartment 35, a second compartment 36, and a third compartment 37. In the embodiment shown, first compartment 35 has a greater height and thickness as compared to compartments 36 and 37. The thickness of the compartments is defined as the dimension between opposing walls for enclosing articles in the compartment in question. The width of all three compartments may be identical, extending across the entire width of cartridge 5.

In a particular embodiment, first compartment 35 is sized and configured with a larger thickness to receive postal flats (e.g., large envelopes, magazines, etc.), and second and third compartments 36 and 37 are sized and configured with a smaller thickness to receive postal envelopes of standard size. Alternatively, the cartridge may comprise two compartments adapted to receive postal flats or similar somewhat larger items. Compartments 35-37 may be open along either side such that postal items may be inserted into the compartments through either open side. However, in order to help ensure that each postal item remains in its respective compartment until being discharged therefrom, the side openings for each compartment may not extend the entire height of the compartment. Thus, the interior base or floor 38 of first compartment 42 may be lower than the lowermost edge 39 of the side opening for first compartment 35. In this manner, when a postal item is inserted into first compartment 35 through the side opening, the postal item will fall downwardly until it reaches base 38 of first compartment 35.

In the exemplary embodiment shown, the base or floor of each compartment 35-37 of cartridge 5 may comprise a closing means such as a hinged door (or discharge gate) 40, as best seen in Fig. 8. Once an article has been inserted into one of the compartments on cartridge 5, and the cartridge is at the appropriate discharge position, the discharge gate 40 may open (as best seen in Fig. 8) such that the article will fall downwardly from the compartment (and thus discharged from cartridge 5). The opening of discharge gates 40 may occur under the direction of a control system for conveyor/sorting system 1 in order to ensure that the article is discharged at the appropriate location. The cartridge 5, and a control board of the cartridge possibly provided on one or more of the cartridges, may receive wireless signals from the control system via a wireless transmitter(s) provided along track assembly 2 (e.g., infrared or RF transmitters positioned along the length of track assembly 2). E.g. via cables the control signal received is transferred to solenoids 41. The power for powering the movement of the solenoids 41 may be provided to a grid of electrical wires on the track of carriers by inductive power transfer or e.g. by a sliding contact. The power may be transferred from the track of carriers and to a solenoid by electrical wires.

The base floor in one or more of the compartments may in embodiments of the present invention form an angled surface. The angled surface may e.g. be established by one hinged edge of the surface situated at a higher horizontal level and an opposite edge of the surface being situated at a lower level. Hereby, the articles are guided towards the edge being positioned at the lower horizontal level of the base of the compartment, and the gate will provide a controlled opening at first during along the opposite edge.

As seen in Fig. 8, discharge gates 40 are hingedly attached to the base of cartridge 5. The gates may be attached by means of, for example, a torsion spring hinge.

Each gate 40 or a group of gates may also or additionally be provided with a solenoid 41. The solenoid may be e.g. a magnet valve of the kind providing a movement of a levering arm 42, connected to the solenoid, by applying a power to the solenoid. Each solenoid 41 may e.g. through a levering arm 42 be operated and disengaging/engaging a lever pawl of the closing means such as to enable opening or locking/closing of the gate. The closing or opening of the gates may take place by the gates gradually being closed/opened by a gate closing means 43 positioned before an induction section at a fixed position. The gate closing means may be one or more elements 43 extending in a direction of travel of the articles on the sorter. The elements 43 may be curved or having an angled cross-section in a way such as to gradually close the gates 41 as the carrier moves along the element 43. In a closed position, the solenoid 41 and the levering arm 42 keeps the gate closed until opening is wanted again. The solenoids 41 and levering arm 42 arrangement is, in the figures 7-9 shown, to be positioned on the opposite side of a permanent open side of the compartments through which permanent openings are inserted into the compartments. One or more of the solenoids 41 may alternatively be positioned on top of each compartment 35-37. By placing the solenoids on top of the compartments the possibility of inserting articles from either side of the compartments is achieved.

The possible plurality of gates on a single cartridge may be configured to open simultaneously and/or individually. Although the control system may send a signal to the cartridge 5 to open one or more of the gates 40, it is also contemplated that a release mechanism may be provided at each discharge position along the conveying path. Although a mechanism for closing the gates after the articles are discharged may be provided on each cartridge, it is also contemplated that a closing element 43 as previously described or other fixed member may be positioned just prior to the induction station for closure of the gates. Closing elements located directly beneath the traveling cartridges may be positioned and configured in such a manner that when a cartridge passes the closing elements, any open discharge gate will be urged to a closed position by the closing elements and a latching mechanism will ensure that the gates remain closed until operated again for article discharge.

Fig. 7 shows carriage assembly 32 supported on main track assembly 2 and including a mounting pin 44 secured to box assembly 45. Mounting pin 44 is used to attach carriage assembly 32 to a moving element such as a chain 46, shown on figure 6, within main track assembly 2. Carriage assembly 32 further includes a first suspension arm 33, and a second suspension arm 34.

In figure 8, one or more control wires may extend through carriage assembly 32 to cartridge 5 in order to provide actuation signals for the controlled opening of the discharge gates provided on the bottom of cartridge 5. Of course, a variety of other means may be employed for providing power to carriage assembly 32, as needed. Main track assembly 2 may be configured in the manner described in detail in the EP 1 044 148 patent. In particular, main track assembly 2 may comprise a monorail assembly, and each carriage assembly 32 is mounted to a drive chain assembly 46, as shown on figure 6.

One possible effect of providing an opening of the one or mores gates 40 by one or more solenoids 41 provided on the cartridge 5 may be a more precise and more reliable opening of the gates 40, than if the gates was to be opened by mechanical means provided at the destination positions. The more precise and reliable opening of the gates by the solenoids will be explained in the following. Mechanical means for opening the gates may be fixed at predetermined positions along the track e.g. at the destination positions. Such mechanical means for opening the gates may e.g. be an activating arm angaging and thereby unlocking a locking mechanism of the gate to be opened. However, due to the running speed of the chain supporting the carriers, the narrow pitch of the chutes and the narrow pitch of the carriers, and the even more narrow pitch of the cartridges provided on each carrier, it may be more difficult to precisely open the gates in such a way compared to opening the gates by the solenoids. The enhanced precision and reliability when using solenoids is e.g. due to the fact that opening of the gates by the solenoids is relying on a signal received by the solenoid from the control system and not by an activating arm engaging the correct locking mechanism at the right moment. Minor changes in the length of the chain and other minor mechanical changes in e.g. the positioning of the cartridges may enhance the reliability of the solenoid solution for opening the gates, compared to opening the gates by e.g. by an activating arm positioned at predetermined positions at the destination positions.

However, the difficulties of the activation means engaging the right locking mechanism at the right moment may be decreased by providing a set of e.g. three activation arms at each destination position.

As further described in EP 1 044 148, a plurality of support and guide wheels may be employed to facilitate movement of carriage assembly 32 along main track assembly 2. Any of the various drive means described in US 6,571,933 may be employed for the controlled movement of carriage assembly 32 along track assembly 2. US 6,571,933 is hereby incorporated by way of reference herein.

Fig. 9 shows a screw drive assembly that may be provided in the main track assembly 2. The screw drive assembly may be provided in the main track assembly 2 and connected to chain assembly 46 for purposes of driving the carriage assemblies 32 along track assembly 2 according to an embodiment of the present invention. Alternatively the chain may be driven by linear motors or the alike known means for providing a driving force to the chain. The sorter speed of the present invention is chosen in the interval between 0,25 m/s and 3,0 m/s, possibly most preferred in the interval between 0,5 and 1,25 m/s.

The sorter systems of the present invention may be provided on multiple levels. Two or more track assemblies and associated cartridges, sorters, etc. may be provided in a stacked arrangement in order to maximize the usage of floor space. Further, a double cartridge sorter, where two cartridges are placed next to each other in a horizontal plane, in a direction perpendicular to the travelling direction of the articles on the sorter, may be beneficial e.g. due to capacity reasons. Still further, such a "double cartridge sorter" may be provided with cartridges, which are fixed or moveable in a transverse direction with respect to the travelling direction of the articles on the sorter. The specific illustrations and embodiments described herein are exemplary only in nature and are not intended to be limiting of the invention defined by the claims. Further embodiments and examples will be apparent to one of ordinary skill in the art in view of this specification and are within the scope of the claimed invention.

Claims

1. A method for transferring articles from an article feeding position to a selected destination along an article conveying system, said method comprising the steps of: - sorting articles in accordance with destination codes assigned to each article,

- displacing the sorted articles from the article feeding position toward and into a number of compartments of a cartridge docked at a first designated position at the article feeding position,

- conveying the cartridge from the first designated position to a second designated position of the article conveying system by means of a conveyor system to which the cartridge is attached and is capable of being transported by, said conveyor system having a conveying direction along a track,

- providing at least one destination buffer, at the second designated position of the article processing machine, said at least one destination buffer intended for conveying the articles, subsequent to opening the aperture at the bottom of the compartment, from the compartment of the cartridge to a destination buffer rest for the articles,

- displacing the at least one destination buffer, at the second designated position of the article conveying system, to one of the at least first destination and second destination, said displacement of the at least one destination buffer being specifically selected, and said displacement being transverse to the conveying direction of the conveyor, and

- subsequent to displacing the at least one destination buffer, discharging the articles from the destination buffer rest to the selected one destination, said discharge of the articles taking place by means of gravity subsequent to a release of the articles from the destination buffer rest towards the selected one destination.

2. A method according to claim 1, wherein

- each of said compartments are having a bottom aperture being closed during conveying of the articles in the compartment of the cartridges from the first designated position to the second designated position of the conveyor system, - subsequent to displacing the one destination buffer, discharging the articles from the compartment of the cartridge to the selected one destination, said discharge of the articles taking place by means of gravity subsequent to opening the aperture at the bottom of the compartment.

3. A method according to claim 2, wherein opening of the aperture closing means is performed by cams exterior to the cartridge and positioned at the destination for controlling opening of the cartridge in response to the cartridge arriving to the destination.

4. A method according to claim 2, wherein opening of the aperture closing means is performed by means forming an integral part of the cartridge and said means being controlled by other means capable of sensing when the cartridge arrives at the destination.

5. A method according to claim 1, said method comprising the steps of:

- providing a primary destination buffer, at the second designated position of the article processing machine, said destination buffer intended for conveying the articles, subsequent to opening the aperture at the bottom of the compartment, from the compartment of the cartridge to a primary rest for the articles, said primary rest constituting part of the primary destination buffer,

- providing a secondary destination buffer, also at the second designated position of the article processing machine, said secondary destination buffer intended for conveying the articles, subsequent to a release of the articles from the primary destination buffer rest to a secondary destination buffer rest for the articles, - displacing the secondary destination buffer, at the second designated position of the article conveying system, to one of the at least first destination and second destination, said displacement of the secondary destination buffer being specifically selected, and said displacement being transverse to the conveying direction of the conveyor, and

- subsequent to displacing the secondary destination buffer, discharging the articles from the secondary destination buffer rest to the selected one destination, said discharge of the articles taking place by means of gravity subsequent to a release of the articles from the secondary destination buffer rest towards the selected one destination.

6. A method according to claim 5, wherein - each of said compartments are having a bottom aperture being closed during conveying of the articles in the compartment of the cartridges from the first designated position to the second designated position of the conveyor system,

- subsequent to displacing the secondary destination buffer, discharging the articles from the compartment of the cartridge to the selected one destination, said discharge of the articles taking place by means of gravity subsequent to opening the aperture at the bottom of the compartment.

7. A method according to claim 6, wherein opening of the aperture closing means is performed by cams exterior to the cartridge and positioned at the destination for controlling opening of the cartridge in response to the cartridge arriving to the destination.

8. A method according to claim 6, wherein opening of the aperture closing means is performed by means forming an integral part of the cartridge and said means being controlled by other means capable of sensing when the cartridge arrives at the destination.

9. A method according to any of the preceding claims 1 or 5, where said displacement of one of the following elements: the one destination buffer or the secondary destination buffer is performed substantially perpendicular to the conveying direction of the conveyor.

10. A method according to any of the preceding claims 1 or 5, where said displacement of one of the following elements: the one destination buffer or the secondary destination buffer, is performed substantially horizontally and substantially perpendicular to the conveying direction of the conveyor.

11. A method according to any of the preceding claims 1 or 5, where said displacement of one of the following elements: the one destination buffer or the secondary destination buffer is performed from a central position placed between the at least first destination and second destination, and transversely to either the at least first destination or second destination, depending on the selection made.

12. A method according to any of the preceding claims 1 or 5, where said displacement of one of the following elements: the one destination buffer or the secondary destination buffer is performed from a central position placed between the at least first destination and second destination, and substantially horizontally to either the at least first destination or second destination, depending on the selection made.

13. A conveyor system for conveying articles, comprising

- an endless track assembly, a plurality of cartridges for receiving articles and for discharging received articles therefrom, said cartridges supported from said track assembly, movable about a conveying path defined by said track assembly, and said conveyor system furthermore comprising

- a plurality of destination buffers for receiving articles being discharged from the cartridges, said destination buffers positioned at a level below said cartridges and being movable transverse to said conveying path between two or more discharge positions.

14. A conveyor system according to claim 13 for conveying articles from an article feeding position to a selected destination along an article conveying system, said system comprising: - a plurality of cartridges being provided with a number of compartments,

- a conveyor system to which the cartridges are attached, said conveyor system having a conveying direction along a track, and said conveyor system capable of conveying a number of cartridges along the track, - said conveyor system having at least a first designated position with means for displacing articled from an article feeding position to one of the compartments of a cartridge positioned at the first designated position,

- said conveyor system furthermore having at least a second designated position with

5 means for discharging the articles from the one compartment of the cartridge to one of at least a first destination and a second destination, and

- a one destination buffer positioned at the second designated position of the conveyor system, said one destination buffer capable of conveying the articles from the compartment of the cartridge to a buffer rest for the articles,

10 - said conveyor system furthermore having means for displacing of the one destination buffer, at the second designated position of the conveyor system, to one of the at least first destination and second destination.

15. A conveyor system according to claim 14, said conveyor system having means for 15 operating the destination buffer rest from a position supporting the articles to a position discharging the articles, and at which discharge position of the destination buffer rest the articles is discharged from the one destination buffer to one of the at least first destination and second destination.

20 16. A conveyor system according to claim 14, and where the first destination is placed at a first position in relation to the track of the conveying system, and the second destination is placed at a second position in relation to the track of the conveying system, and said first and second position is transversely displaced in relation to each other with respect to said conveying direction, and wherein the first destination is positioned as trailing and the

25 second destination is positioned as leading in relation to the conveying direction of the cartridges.

17. A conveyor system according to claim 14, and where the first destination is placed at a first position in relation to the track of the conveying system, and the second destination is 30 placed at a second position in relation to the track of the conveying system, and wherein the first destination and the second destination are substantially similarly positioned, and hereby none of the destinations are leading or trailling, in relation to the conveying direction of the track.

35 18. A conveyor system according to claim 14, where at least one of the at least first destination and second destination is constituted by a bin for collecting a plurality of articles.

19. A conveyor system according to claim 14, where at least one of the at least first destination and second destination is constituted by a delimitation of a conveyor belt.

20. A conveyor system according to claim 13, wherein each of said compartments are

5 having a bottom aperture being capable of being closed by one or more aperture closing means, and said article conveying system having means for operating the aperture closing means from a closed position to an open position, at which open position of the apertures of the compartments the articles is capable of being discharged from the cartridges to the one destination buffer. 10

21. A conveyor system according to claim 20, wherein the aperture closing means is constituted by cams exterior to the cartridge and positioned at the destination for controlling opening of the cartridge in response to the cartridge arriving to the destination.

15 22. A conveyor system according to claim 20, wherein the aperture closing means is constituted by means forming an integral part of the cartridge and said means being controlled by other means capable of sensing when the cartridge arrives at the destination.

23. A conveyor system according to claim 22, wherein the aperture closing means is 20 constituted by an electrically operated lever, said lever capable of engaging and disengaging a lever pawl constituting part of a closure for closing at least one the aperture of the cartridge.

24. A conveyor system according to claim 13, wherein the cartridge is provided with at 25 least two compartments, where each of the at least two compartments has opposing walls enclosing the articles within the compartment, and where at least one of the at least two compartments has a greater distance between the opposing walls of the compartment than a distance between corresponding opposing walls of the at least other compartment.

30 25. A conveyor system according to claim 13, wherein the cartridge is provide with three compartments, where each of the three compartments has opposing walls enclosing the articles within the compartments, and where one of the three compartments has a greater distance between the opposing walls of the compartment than a distance between corresponding opposing walls of the other two compartments.

35

26. A conveyor system according to claim 13, where the at least one compartment having a greater distance between the opposing walls than the other compartments is positioned trailing the other compartments in relation to a conveying direction of the conveyor system.

27. A conveyor system according to claim 13, where the at least one compartment having a greater distance between the opposing walls than the other compartments is positioned leading the other compartments in relation to a conveying direction of the conveyor system.

28. A conveyor system according to claim 13, where the at least one compartment having a greater distance between the opposing walls than the other compartments is positioned intermediate other compartments in relation to a conveying direction of the conveyor system.

29. A conveyor system according to claim 13, wherein the cartridges are suspended from a conveying track positioned at a horizontal level higher than the horizontal position of the cartridges, and where suspension arms support the cartridges in the conveying track.

30. A conveyor system for conveying articles, comprising

- a plurality of primary destination buffers and secondary destination buffers for receiving articles being discharged from the cartridges, said primary destination buffers and secondary destination buffers positioned at a level below said cartridges,

- said primary destination buffers being fixed in relation to said conveying path, and said secondary destination buffers being movable transverse to said conveying path between two or more discharge positions.

31. A conveyor system according to claim 30 for conveying articles from an article feeding position to a selected destination along an article conveying system, said system comprising:

- a plurality of cartridges being provided with a number of compartments,

- said conveyor system furthermore having displacement means for moving the cartridge transverse to said conveying path between two or more positions, and hereby discharging the articles from the one compartment of the cartridge to one of at least a first destination and a second destination, and

- a primary destination buffer positioned at the second designated position of the conveyor system, said primary destination buffer capable of conveying the articles from the

5 compartment of the cartridge to a first buffer rest for the articles,

- a secondary destination buffer positioned at the second designated position of the conveyor system, said secondary destination buffer capable of conveying the articles from the primary destination buffer to a second buffer rest for the articles,

- said conveyor system furthermore having means for displacing of the secondary

10 destination buffer, at the second designated position of the conveyor system, to one of the at least first destination and second destination.

32. A conveyor system according to claim 31, said conveyor system having means for operating the primary destination buffer rest from a position supporting the articles to a

15 position discharging the articles, and at which discharge position of the primary destination buffer rest the articles is discharged from the primary destination buffer to the secondary destination buffer.

33. A conveyor system according to claim 31, said conveyor system having means for 20 operating the secondary buffer rest from a position supporting the articles to a position discharging the articles, and at which discharge position of the secondary destination buffer rest the articles is discharged from the secondary destination buffer to one of the at least first destination and second destination.

25 34. A conveyor system according to claim 31, and where the first destination is placed at a first position in relation to the track of the conveying system, and the second destination is placed at a second position in relation to the track of the conveying system, and said first and second position is transversely displaced in relation to each other with respect to said conveying direction, and wherein the first destination is positioned as trailing and the

30 second destination is positioned as leading in relation to the conveying direction of the cartridges.

35. A conveyor system according to claim 31, where said at least first destination and second destination is placed at substantially the same horizontal level below the cartridge, 35 and where the first destination is placed at a first position in relation to the track of the conveying system, and the second destination is placed at a second position in relation to the track of the conveying system, and wherein the first destination and the second destination are substantially similarly positioned, and hereby none of the destinations are leading or trailling, in relation to the conveying direction of the track.

36. A conveyor system according to claim 31, where at least one of the at least first destination and second destination is constituted by a bin for collecting a plurality of articles.

5

37. A conveyor system according to claim 31, where at least one of the at least first destination and second destination is constituted by a delimitation of a conveyor belt.

38. A conveyor system according to claim 30, wherein each of said compartments are 10 having a bottom aperture being capable of being closed by one or more aperture closing means, and said conveyor system having means for operating the aperture closing means from a closed position to an open position, at which open position of the apertures of the compartments the articles is capable of being discharged from the cartridges to one of the at least first destination and second destination. 15

39. A conveyor system according to claim 38, wherein the aperture closing means is constituted by cams exterior to the cartridge and positioned at the destination for controlling opening of the cartridge in response to the cartridge arriving to the destination.

20 40. A conveyor system according to claim 38, wherein the aperture closing means is constituted by means forming an integral part of the cartridge and said means being controlled by other means capable of sensing when the cartridge arrives at the destination.

41. A conveyor system according to claim 40, wherein the aperture closing means is 25 constituted by an electrically operated lever, said lever capable of engaging and disengaging a lever pawl constituting part of a closure for closing at least one the aperture of the cartridge.

42. A conveyor system according to claim 30, wherein the cartridge is provided with at 30 least two compartments, where each of the at least two compartments has opposing walls enclosing the articles within the compartment, and where at least one of the at least two compartments has a greater distance between the opposing walls of the compartment than a distance between corresponding opposing walls of the at least other compartment.

35 43. A conveyor system according to claim 30, wherein the cartridge is provide with three compartments, where each of the three compartments has opposing walls enclosing the articles within the compartments, and where one of the three compartments has a greater distance between the opposing walls of the compartment than a distance between corresponding opposing walls of the other two compartments.

44. A conveyor system according to claim 30, where the at least one compartment having a greater distance between the opposing walls than the other compartments is positioned trailing the other compartments in relation to a conveying direction of the conveyor system.

45. A conveyor system according to claim 30, where the at least one compartment having a greater distance between the opposing walls than the other compartments is positioned leading the other compartments in relation to a conveying direction of the conveyor system.

46. A conveyor system according to claim 30, where the at least one compartment having a greater distance between the opposing walls than the other compartments is positioned intermediate other compartments in relation to a conveying direction of the conveyor system.

47. A conveyor system according to claim 30, wherein the cartridges are suspended from a conveying track positioned at a horizontal level higher than the horizontal position of the cartridges, and where suspension arms support the cartridges in the conveying track.