LINEAR SORTER HAVING VARIABLY RUNNING CROSS-BELT SUPPORTS

Abstract

A linear sorter sorts piece goods. The linear sorter contains a closed circulation of tracks having a plurality of cross-belt elements, in which the piece goods are transported on an upper run on the cross-belt elements and are sorted by unloading to corresponding destination points, and the cross-belt elements return on a lower run. The cross-belt elements are driven by linear motors. In order to simplify the maintenance and to have to keep fewer cross-belt elements available as replacement components, the linear motors for the cross-belt elements are controlled such that, as the cross-belt elements return on the lower run, the speed of the cross-belt elements is higher than the speed of the cross-belt elements while travelling on the upper run.

Claims

1-8. (canceled)

9. A line sorter for sorting piece goods, the line sorter comprising: a closed loop having tracks and a plurality of cross-belt carriages, wherein the piece goods being transported in a sorting direction on an upper strand of said closed loop on said cross-belt carriages and being sorted by discharging to corresponding destination points and, wherein said cross-belt carriages return on a lower strand of said closed loop; and one drive means provided per cross-belt carriage of said cross-belt carriages, said one drive means being actuated such that each of said cross-belt carriages on said closed loop can each have an individual speed.

10. The line sorter according to claim 9, wherein said plurality of cross-belt carriages is formed as a group, so said cross-belt carriages of said group on said upper strand have an identical adjustable speed.

11. The line sorter according to claim 9, wherein each of said one drive means for said cross-belt carriages are actuated such that as said cross-belt carriages return on said lower strand their speed is higher (V.sub.ret>V.sub.sort) than a speed of said cross-belt carriages when traveling on said upper strand.

12. The line sorter according to claim 9, wherein a size of the piece goods to be sorted is detected, and on a basis of the size, a number of said cross-belt carriages required for transference is defined, and wherein each of said one drive means for a required number of said cross-belt carriages are actuated on a basis of a specified transfer position of the piece goods on the line sorter such that the piece goods to be sorted can be placed onto the required number of said cross-belt carriages.

13. The line sorter according to claim 9, wherein said one drive means is a linear motor, which per said cross-belt carriage, is formed by a permanent magnet and by a series of electromagnets generating an alternating field, wherein said series of electromagnets are disposed in said upper and lower strands and one said permanent magnet is disposed in each said cross-belt carriage.

14. The line sorter according to claim 9, wherein after discharging the piece goods at a last target point in the sorting direction, a relevant said cross-belt carriage is accelerated.

15. The line sorter according to claim 9, wherein said closed loop has one of said tracks disposed on each of two sides along said closed loop for a guide of said cross-belt carriages, wherein said guide of said cross-belt carriages is provided with a support alternately only on one of said tracks and said support extends over an immediately adjacent one of said cross-belt carriages.

16. The line sorter according to claim 15, wherein said cross-belt carriages each have a roller that meshes with the other of said two tracks on a side of each of said cross-belt carriages facing away from said support.

Description

[0022] The invention will be explained by way of example and in more detail below with reference to the drawings. In the drawings:

[0023] FIG. 1 shows line sorter with cross-belt carriers according to documents [4] and [5] prior art,

[0024] FIG. 2 shows line sorter with cross-belt carriages in an embodiment of the present invention.

[0025] FIG. 1 shows the habitual prior art with a line sorter 1, wherein the cross-belt carriages 110 are permanently coupled together. Each cross-belt carriage 110 comprises a cross-belt 116. This prior art can also be found in the patent application according to document [6], which was only recently published, in which a linear motor is likewise provided for the drive of the cross-belt carriages. See, for example, FIG. 3 in said document [6]. It is only in order to be able to easily establish the relationship to documents [4] and [5] that the reference characters of those documents have been used. Reference is made to FIG. 1 in document [3] in respect of the arrangement of the destination points along a line sorter. The target points are provided with the term “discharge” in this document.

[0026] FIG. 2 shows a line sorter 1 according to one embodiment of the present invention. Contained on a path with guide tracks 31 (not shown in detail in FIG. 2), the cross-belt carriages 21 run freely among one another to the extent that each cross-belt carriage is individually driven by drive means. The drive means can be a conventional electric motor. It is preferably a linear motor, however (not shown in FIG. 2). The individual drive of the cross-belt carriages obviously presupposes that the individual cross-belt carriages 21 are not mechanically coupled together, contrary to the habitual prior art according to documents [1] to [6], therefore.

[0027] Owing to the omission of the coupling of the individual cross-belt carriages 21, the following should be arranged in respect of track guiding along the path 31:

[0028] To achieve adequate track guiding with what are known as “narrow” or “short” cross-belt carriages 21, the support of the cross-belt carriage 21 in the sorting direction sort has to be longer than that of the width b of a cross-belt carriage 21. This can be achieved by a cross-belt carriage 21 only ever being guided in the track 30 on one side and the following cross-belt carriage 21 being guided on the other side of the track 30. In this way, the width of the guide in the track is slightly less than three times the width b of a cross-belt carriage 21. In addition it can be provided that, opposite the wide guide, only one roller meshes in the guide 30, so the width of the guide 30 becomes slightly narrower but is still more than twice the width b of a cross-belt carriage 21.

[0029] If, contrary to said habitual prior art, the cross-belt carriages 21 are now NOT coupled but loosely run one after another, the number of cross-belt carriages 21 can be reduced. Located on the upper strand 31 is a series of cross-belt carriages 21 moving one after another and whose gap 20 is adjustable, likewise due to the individual actuation of every linear motor per cross-belt carriage 21. As soon as the piece goods 10 are discharged at the end of the sorting line in a discharge direction 11, 11′, the cross-belt carriages 21 are greatly accelerated one after the other and return on the lower strand 32 at a much higher speed V.sub.ret. This higher speed V.sub.ret refers to the typical (lower) sorting speed V.sub.sort. Gaps form between the cross-belt carriages in the process. The number of cross-belt carriages 21 over the entire line is much lower then with endlessly coupled cross-belt carriages 21, therefore. In relation to the term “strand”, reference is made at this point to document [8] for an explanation thereof.

[0030] In relation to the term “linear motor”, reference is made firstly to document [7]. Secondly, the linear motor per cross-belt carriage 21 is formed by a permanent magnet, which is permanently arranged in the cross-belt carriage 21 and by a series of electromagnets generating an electromagnetic alternating field. These electromagnets are successively arranged in the two strands 31 and 32 and in the regions called turning points here, which connect the two strands 31 and 32.

[0031] Just before the “emergence” of the cross-belt carriages 21 on the upper strand 31 for renewed loading, the return carriages on the upper column of cross belt carriages 21, which is running in a gap-free manner, catch up, but at least the time-dependent position of the carriages/carriers is matched to the goods to be transferred. Said “emergence” takes place at the turning point introduced above.

[0032] A plurality of cross-belt carriages on the upper strand 31 can be combined particularly advantageously into a group in order to process larger piece goods on the line sorter 1. Larger piece goods means that piece goods of this kind have to be placed on a plurality of cross-belt carriages 21. For this, the dimension (size) of the piece goods 10 to be processed has to be recorded. The number of required cross-belt carriages 21 can be defined using this dimension and the known width b of a cross-belt carriage 21—cf. FIG. 2. The transfer position is specified by the construction, and the transfer time of piece goods to be sorted on the linear conveyer is specified by the underlying IT system. As a result, the cross-belt carriages 21 arriving from the lower strand 32 via the diversion, due to the individual capacity for actuation, may be actuated such that the piece goods 10 to be sorted can be placed exactly onto the defined number of cross-belt carriages 21. With the designated sorting destination all cross-belts 21 of the relevant cross-belt carriages 21 are accordingly activated in order to discharge the piece goods in one of the discharge directions 11, 11′. The group formation is provided purely virtually for particular piece goods. After discharging of the piece goods, the cross-belt carriages that have become available no longer belong to a group.

[0033] The individual capacity for actuation of the cross-belt carriages 21 also allows a large number of configurations on the upper strand 31 in order to feed the piece goods 1 to be sorted optimally to the destination points. A variably adjustable speed V.sub.sort, for example, is also conceivable, wherein this speed V.sub.sort can be defined depending on the type, mass and dimension of the piece goods 1 to be sorted.

[0034] In summary, the invention allows free circulating of a plurality of cross-belt carriages 21 with adjustable gaps and adjustable individual speeds, comparable to the cars on a lane of a freeway. Overtaking of cross-belt carriages 21 is ruled out more or less by definition in the case of a line sorter 1.

LIST OF REFERENCE CHARACTERS, GLOSSARY

[0035] 1 line sorter [0036] 10 piece goods, packet [0037] 11, 11′ discharge direction [0038] 20 interval, distance, gap [0039] 21 cross-belt carriage, cross-belt carrier, carriage, carrier [0040] 22 cross-belt [0041] 30 guiding track, guide [0042] 31 upper strand [0043] 32 lower strand [0044] 108 belt [0045] 110 cross-belt carriage, carriage, cross-belt carrier, carrier, carriage according to the prior art [0046] 116 cross-belt [0047] 802 conveyance portion [0048] ret return direction [0049] sort sorting direction [0050] V.sub.sort speed of the cross-belt carriages in the sorting direction [0051] V.sub.ret speed of the cross-belt carriages on return

LIST OF CITED DOCUMENTS

[0052] [1] WO 2016/206695 A1 “LINE SORTER”; BEUMER GROUP A/S, DK-8200 Aarhus N [0053] [2] WO 2017/092763 A1 “SORTER WITH REDUCED POYGON EFFECT”; BEUMER GROUP A/S, DK-8200 Aarhus N [0054] [3] WO 2017/108048 A1 “LINE SORTER WITH ADJUSTABLE TRACK LENGTH”; BEUMER GROUP A/S, DK-8200 Aarhus N [0055] [4] U.S. Pat. No. 9,809,388 B2 “CROSS BELT SLAT SORTER”; Bastian Solutions, LLC, Indianapolis UN (US) [0056] [5] U.S. Pat. No. 9,409,716 B2 “CROSS BELT SLAT SORTER”; Bastian Solutions, LLC, Indianapolis UN (US) [0057] [6] US 2018/0170690 A1 “LINE SORTER”; BEUMER GROUP A/S, DK-8200 Aarhus N [0058] [7] [Linear motor https://de.wikipedia.org.wiki/Linearmotor [0059] [8] Strand designates a part or branch of a running tensile unit https://de.wikipedia.org/wiki/Trum_(Maschinenbao)