SYSTEM FOR BUFFER STORAGE AND SEQUENCE OF LOADS UPPER AT LEAST ONE PREPARATION STATION

Description

1. DOMAINE TECHNIQUE

[0001] The field of invention is logistics.

[0002] The present invention relates more specifically to a buffer storage and load sequencing system, configured to receive unsequenced loads from at least one external unit (for example an automated storage / retrieval warehouse) and supply sequenced loads to at least one preparation station. By "supply of sequenced loads", we mean the supply, under a delivery constraint, of at least one sequence comprising loads in a desired order.

[0003] The present invention can be applied to any type of preparation station, and in particular but not exclusively: at order preparation stations (also called "picking stations"), by picking products from storage containers (also called "source loads"): an operator (or a robot) receives a picking list (on paper, on a terminal screen, in voice format, in the form of a computer task (in the case of the robot), etc.) indicating to him, for each package to be shipped (also called "shipping container" or "target load"), the quantity of each type of product that he must collect from storage containers and group together in the package to be shipped; and at storage container palletizing stations (also called "source loads") themselves containing products: an operator (or a robot) receives a picking list (on paper, on a terminal screen, in voice format, in the form of a computer task (in the case of the robot), etc.) indicating to him, for each pallet to be shipped (also called “shipping container” or “target load”), the quantity of each type of storage container (for example, cartons) that he must collect and unload onto the pallet to be shipped. 2. ARRIÈRE-PLAN TECHNOLOGIQUE

[0004] We now present, in relation to the figure 1 , a top view of an example of a known configuration for an automated order picking system comprising: an automated storage / retrieval warehouse 7 comprising several (two in this example) assemblies each formed by an aisle 7a, 7a' serving on either side a storage shelf 7b, 7c, 7b', 7c' with several levels of superimposed storage; a set of conveyors bringing the source loads from the automated warehouse 7 to preparation stations, and vice versa. In the example of the figure 1 , we distinguish: o for the outward journey (i.e. from the automated store 7 to the preparation stations), conveyors referenced 9a and 9a' (one per aisle) as well as 6 and 8; and o for the return journey (i.e. from the preparation stations to the automated store 7), conveyors referenced 8', 6' as well as 9b and 9b' (one per aisle); in this example, conveyors 6' and 8' are superimposed on conveyors 6 and 8; several order preparation stations 10a to 10f, each occupied by an operator 1a to 1f and extending perpendicularly to the conveyors referenced 8 and 8'; and a control system (also called a “control unit”), which is a central management computer system responsible for controlling the entire system (automated storage / retrieval warehouse 7, set of conveyors 6, 6', 8, 8', 9a, 9a', 9b and 9b', and preparation stations 10a to 10f).

[0005] The control system also manages the order list associated with each shipping container (target load) and therefore the order of the order lines forming this list, depending on the location of the storage containers (source loads) in the automated warehouse 7, the availability of the trucks and forks in the automated warehouse 7, as well as the product requirements of the various shipping containers to be prepared which follow one another at the preparation station. This is intended to optimize all movements and preparation times of the shipping containers and to ensure synchronization between the arrival, at the preparation station, of a shipping container and the corresponding storage containers (i.e. containing the products indicated in the order list associated with this storage container).

[0006] In the example of the figure 1 , each preparation station comprises two conveyor circuits: a first conveyor circuit for the storage containers, formed by two horizontal columns of conveyors: one (forward column 2) for moving the storage containers from the third conveyor subset 8 to the operator 1a, and the other (return column 3) for the reverse movement; and a second conveyor circuit for the shipping containers, formed by two horizontal columns of conveyors: one (forward column 4) for moving the shipping containers from the third conveyor subset 8 to the operator 1a, and the other (return column 5) for the reverse movement.

[0007] A buffer storage function (also called "accumulation function") of a determined quantity of containers upstream of the operator (or the automaton) is carried out, in each of the first and second circuits, by the forward column 2 and 4 (composed of conventional horizontal conveyors). A storage container therefore follows the following path: it is picked up by a trolley in the automated store 7, then conveyed successively by one of the conveyors 9a and 9a' (depending on whether it arrives from aisle 7a or 7a'), then by the conveyors 6 and 8, and finally by the conveyors of the forward column 2, to be presented to the operator. In the other direction (after presentation to the operator), the storage container follows the reverse route: it is conveyed by the conveyors of return column 3, then by conveyors 8' and 6', and finally by one of conveyors 9b and 9b' (depending on whether it returns to aisle 7a or 7a'), before being replaced in the automated store 7 by a trolley.

[0008] As mentioned above, the containers (source loads and target loads) must be presented to the operator in a desired order forming at least one determined sequence. Conventionally, this order of arrival is predetermined by the control system (i.e. determined, for each container, before this container reaches the preparation station) and, if necessary, recalculated during the routing of the containers from the exit of the automated store 7 to the preparation station (for example to take into account a breakdown of an element of the system).

[0009] In a first known (standard) implementation, a first level of sequencing is achieved by depositing pre-sequenced loads on each of the conveyors 9a and 9a' (there are therefore constraints on the automated store 7). In other words, the loads deposited on the conveyor 9a are in an order consistent with the desired final order, and the loads deposited on the conveyor 9a' are also in an order consistent with the desired final order. Then, a second level of sequencing is achieved by depositing the loads coming from the conveyors 9a and 9a' in the desired final order on the conveyor 6.For example, for a sequence of seven loads, if the loads of ranks 1, 2, 4 and 5 are stored in aisle 7a they are deposited in this order on the conveyor 9a and if the loads of ranks 3 and 6 are stored in aisle 7a' they are deposited in this order on the conveyor 9a'; then the seven loads are deposited on the conveyor 6 in the ascending order (from 1 to 7) of their ranks.

[0010] In a second known implementation, in order to relax the constraints on the automated store 7, it is assumed that the containers do not leave the automated store 7 in the desired order (i.e. the order in which they must be presented to the operator). It is therefore necessary to carry out a container sequencing operation between the automated store 7 and the preparation station where the operator is located. The removal of the sequencing constraints usually weighing on the automated store 7 allows a significant increase in its performance (and more generally of the various upstream equipment), and therefore a reduction in its size and complexity, and therefore its cost. In the example of the figure 1 , this sequencing operation is carried out as follows: the storage containers circulate in a loop on conveyors 6, 8, 8' and 6', and when the storage container expected on the conveyors of the forward column 2 arrives in front of the latter (in order to complete the sequence of storage containers expected at the preparation station), it is transferred to the conveyors of the forward column 2, the other storage containers continuing to circulate in the aforementioned loop (conveyors 6, 8, 8' and 6'). This process is carried out for each of the storage containers expected in the sequence (i.e. in the desired order of arrival at the preparation station).

[0011] The two known implementations mentioned above (based on conventional horizontal conveyors), to perform the buffer storage (accumulation) and sequencing functions, have several drawbacks.

[0012] First of all, they have too high a consumption of m 2 < at low rolling plane height (typically 750 mm). As an example of this excessively high footprint, the surface area required for six order preparation stations (as in the example of the figure 1 ) is of the order of 100 m 2< .

[0013] Another disadvantage is that the floor density of conventional horizontal conveyors (included in the preparation stations) is such that it makes maintenance access to these conveyors difficult (conveyor belt too dense).

[0014] Another disadvantage is that, unless the footprint of the preparation station is further increased (by increasing the length of the forward column of each of the first and second circuits), it is not possible to increase the number of containers that can be accumulated (buffer storage) upstream of the operator (or the machine).

[0015] The invention, in at least one embodiment, aims in particular to provide a buffer storage and charge sequencing system making it possible to overcome the drawbacks of the known technique of figure 1 . Further, document CA 2 735 988 A1 discloses a buffer storage and charge sequencing system according to the preamble of claim 1. 3. RÉSUMÉ

[0016] According to the invention, a buffer storage and load sequencing system is defined, configured to receive unsequenced loads from at least one external unit, via at least one input forward conveyor included in said system, and to supply sequenced loads to at least one preparation station, via at least one output forward conveyor included in said system, said system comprising: an alternative elevator comprising a single nacelle comprising K levels, each allowing at least one load to be transported, with K ≥ 2; at least one buffer storage unit comprising a plurality of buffer locations, distributed over a plurality of levels and each configured to temporarily receive at least one load from the alternative elevator; and a control unit configured to organize: * first movements of loads from said at least one inlet forward conveyor to said at least one buffer storage unit, via the alternative elevator;and * second movements of loads from said at least one buffer storage unit to said at least one outbound conveyor, via the alternating elevator, under a delivery constraint on said at least one outbound conveyor of at least one sequence comprising loads in a desired order, and where the control unit is configured to further organize third movements of loads via the alternating elevator, for loads having been processed by said at least one preparation station, from at least one inbound return conveyor, included in said system, to at least one of the entities belonging to the group comprising: said at least one buffer storage unit, for loads to be stored again; said at least one outbound conveyor, for loads to be presented again to said at least one preparation station, under said delivery constraint;and- at least one output return conveyor included in said system, for loads to be returned to at least one of the entities belonging to the group comprising said at least one external unit, at least one other preparation station and at least one other external unit; and wherein said system comprises, between the reciprocating elevator and said at least one output forward conveyor: an output transfer device comprising K levels each allowing at least one load to be received; and an output sequencer provided with vertical movement means; and in that the control unit is configured to control: a transfer of a group of N loads, from said at least one buffer storage unit to the reciprocating elevator, with N less than or equal to a capacity of the reciprocating elevator in number of loads; a transfer, simultaneously on the K levels, of each group of N loads from the reciprocating elevator to the output transfer device;and a transfer of each group of N loads, via the output sequencer, from the output transfer device to said at least one output forward conveyor, under said delivery constraint.;

[0017] The general principle of the proposed system consists of performing the buffer storage and load sequencing functions using, according to a completely new and inventive approach, a multi-level reciprocating elevator (with a single nacelle comprising K levels) in combination with at least one buffer storage unit, under the control of a control unit configured to organize first load movements and second load movements.

[0018] The at least one external unit (which provides the non-sequenced loads) belongs, for example, to the following non-exhaustive list: an automated storage / retrieval warehouse and at least one other buffer storage and load sequencing system.

[0019] The sequencing capacity (schedulability) of the proposed system is related to the amount of loads that can be temporarily stored in the at least one buffer storage unit.

[0020] The proposed solution has many advantages, including but not limited to: minimization of sequencing constraints at the output of the external unit(s) by sequencing downstream of the latter, and as close as possible to the preparation station(s); this minimization of constraints makes it possible to reduce the size and complexity, and therefore the cost, of the external unit(s); reduction of the footprint; optimization of the efficiency of the overall system (including in particular the external unit(s), the buffer storage and sequencing system and the preparation station(s); optimization of the responsiveness of the overall system; handling of multi-format loads if motorized rollers are used; optimization of costs if the overall system includes several preparation stations (pooling of the buffer storage and sequencing system); etc.

[0021] At the output of the buffer storage and sequencing system, several types of load sequences can be achieved, including but not limited to: a sequence comprising only source loads, each source load being a storage container of product(s); or a sequence comprising only target loads, each target load being a shipping container of product(s); or a sequence comprising a target load, which is a shipping container of product(s), followed by at least one source load, which is a storage container of product(s).

[0022] Several buffer storage and sequencing systems (each implemented according to the proposed solution) can be used in parallel. For example, upstream of at least one preparation station, a first buffer storage and sequencing system is used only for source loads, and in parallel a second buffer storage and sequencing system is used only for target loads.

[0023] Various implementations and features are specified in the set of claims. They are also detailed (with their associated advantages) and illustrated through examples in the remainder of the description. 4. LISTE DES FIGURES

[0024] Other characteristics and advantages of the invention will appear on reading the following description, given as an indicative and non-limiting example, and the appended drawings, in which: there figure 1 , already described in relation to the prior art, is a top view of an automated order preparation system; the figure 2 is a side view of a first example of a buffer storage and load sequencing system according to the invention; figure 3 is a side view of a second example of a buffer storage and load sequencing system according to the invention; figure 4 is a side view of a third example of a buffer storage and load sequencing system according to the invention; figure 5 is a side view of a fourth example of a buffer storage and charge sequencing system according to the invention; figure 6 is a side view of a fifth example of a buffer storage and charge sequencing system according to the invention; figure 7 is a side view of a sixth example of a buffer storage and charge sequencing system according to the invention; figure 8 is a side view of a seventh example of a buffer storage and charge sequencing system according to the invention; figure 9 is a side view of an eighth example of a buffer storage and charge sequencing system according to the invention; figures 10a, 10b and 10c are side, top and front views respectively of a ninth example of a buffer storage and charge sequencing system according to the invention; figures 11a, 11b and 11c are side, top and front views respectively of a tenth example of a buffer storage and charge sequencing system according to the invention; figures 12a, 12b et 12c are side, top and front views respectively of an eleventh example of a buffer storage and charge sequencing system according to the invention; figures 13a, 13b et 13c are side, top and front views respectively of a twelfth example of a buffer storage and charge sequencing system according to the invention; and the figure 14 presents an example of the structure of a control unit according to a particular embodiment of the invention. 5. DESCRIPTION DÉTAILLÉE

[0025] There figure 2 illustrates a first example of a buffer storage and load sequencing system according to the invention. It is configured to receive unsequenced loads from an external unit UE, via an input forward conveyor CAE, and supply sequenced loads to a preparation station PP (occupied by an operator or a robot), via an output forward conveyor CAS. The external unit UE is for example an automated storage / retrieval warehouse.

[0026] In one variant, the external unit UE is another buffer storage and load sequencing system. In another variant, the buffer storage and load sequencing system receives unsequenced loads from several external units (either via several CAE input forward conveyors each specific to one of the external units, or via a CAE input forward conveyor used jointly by several external units).

[0027] The buffer storage and load sequencing system includes an alternative elevator EA, two buffer storage units UST1, UST2 and a control unit UP.

[0028] The reciprocating elevator EA is a discontinuous type vertical elevator, comprising a single nacelle 21 performing reciprocating vertical movements (the nacelle rises and falls alternately). In contrast, a “continuous elevator” (also called “paternoster”) is a vertical elevator comprising a plurality of nacelles circulating in a closed loop, without reciprocating movement. The single nacelle 21 has K levels, with K ≥ 2 each comprising a location (or position) configured to receive a load. In the example illustrated in the figure 2 , the single nacelle 21 has two levels 22a, 22b (K=2).

[0029] The alternative elevator therefore has a capacity of 2x1 loads. Each of the cradle locations is, for example, equipped with a motorized conveyor section (or any transfer device) allowing a load to be transferred onto or off the cradle. In a variant, each cradle location is equipped with free rollers, the movement of which is, for example, ensured by a retractable mechanical means positioned at the end of another piece of equipment (conveyor or buffer location). Other means of movement can be considered.

[0030] Each of the two buffer storage units UST1, UST2 comprises a plurality of buffer locations 23, distributed over a plurality of levels (one buffer location per level) and each configured to temporarily receive at least one load from the alternative elevator. The two buffer storage units UST1, UST2 are arranged vertically on either side of the alternative elevator EA. Each of the levels of the nacelle of the alternative elevator EA can come opposite each of the levels of each of the buffer storage units UST1, UST2 for a transfer of at least one load. The use of two buffer storage units thus arranged makes it possible to increase the capacity and the rate of the buffer storage and sequencing system.

[0031] In a particular implementation for limiting the movements of the alternative elevator EA, the pitch (i.e. the spacing between two successive levels) of the nacelle of the alternative elevator EA is equal to or is a multiple of the pitch (i.e. the spacing between two successive levels) of the buffer storage units UST1, UST2.

[0032] The UP control unit makes it possible to optimally organize the movements of loads in the system, and in particular on the alternating elevator EA and the buffer storage units UST1, UST2, in order to make source loads available on the outbound conveyor CAS according to a determined sequence. For this purpose, the UP control unit receives information (in particular a load identifier) read, on the loads passing at different locations in the system, by reading devices (not shown), such as barcode readers, RFID tag readers, etc. These locations are for example located at the ends of the different conveyors.

[0033] More specifically, the control unit UP organizes first movements of loads from the input forward conveyor CAE to the buffer storage units UST1, UST2, via the alternative elevator EA. It also organizes second movements of loads from the buffer storage units UST1, UST2 to the output forward conveyor CAS, via the alternative elevator EA, under a constraint of delivery on the output forward conveyor CAS of at least one sequence comprising loads in a desired order.

[0034] In a particular implementation, part of the first load movements are performed at the same time as part of the second load movements.

[0035] For example, the UP control unit is configured to organize, whenever possible: a transfer of first charges (for example those noted “a” and “b” on the figure 1 ) from the alternative elevator EA to the buffer storage units UST1, UST2 at the same time as a transfer of second loads (for example those marked “c” and “d” on the figure 1 ) from the buffer storage units UST1, UST2 to the alternative elevator EA. Failing this, these two transfers are carried out successively; and / or a transfer of the second loads from the alternative elevator EA to the outgoing conveyor CAS at the same time as a transfer of third loads (not shown on the figure 1 ) from the CAE inlet forward conveyor to the EA alternative elevator. Otherwise, these two transfers are carried out successively.

[0036] This combination of first and second load movements allows the throughput of the buffer storage and sequencing system to be increased.

[0037] On the figure 1 (and also in the other figures described below), certain loads are referenced with letters ("a", "b", "c", "d") to illustrate the operation of the system. In order to show successive positions of the same load on the same figure, the following notation is used: for a first position, the load is referenced only with its associated letter (for example "a"), for a second position, the load is referenced with its associated letter followed by the prime symbol (for example "a'"), for a third position, the load is referenced with its associated letter followed by the double prime symbol (for example "a""), etc. Thus, on the figure 1 , the load “a” is first on the inlet forward conveyor CAE, then on the alternative elevator EA (it is then noted “a'”), and finally in one of the buffer storage units UST1, UST2 (it is then noted “a''”).

[0038] There figure 3 illustrates a second example of a buffer storage and load sequencing system according to the invention. It differs from the first example illustrated in the figure 1 in that it also supplies sequenced loads to another preparation station PP', via another outbound conveyor CAS'. The two outbound conveyors CAS, CAS' are located on two different levels. In one variant, the number of preparation stations is greater than two. In another variant, the same outbound conveyor CAS is used in combination with a suitable switching system, to serve several preparation stations.

[0039] There figure 4 illustrates a third example of a buffer storage and load sequencing system according to the invention. It differs from the first example illustrated in the figure 1 in that it includes an input return conveyor CRE allowing the return to the alternative elevator EA of loads having been processed by the preparation station PP.

[0040] In this example, the inbound forward conveyor CAE and the outbound forward conveyor CAS are positioned at the same height (level referenced “Level 1”), on either side of the alternative elevator EA. The inbound return conveyor CRE is positioned at a lower height (level referenced “Level 0”). The outbound forward conveyor CAS and the inbound return conveyor CRE are parallel and vertically adjacent. In a particular implementation, they have a vertical spacing between them equal to a vertical spacing between two successive levels of the basket of the alternative elevator EA.

[0041] For loads returning from the preparation station PP, the control unit UP is configured to further organize third movements of loads from the return input conveyor CRE to one or more entities accessible via the alternative elevator EA, in particular: the buffer storage units UST1, UST2, for loads to be stored again; and the outbound conveyor CAS, for loads to be presented again at the preparation station PP, under the delivery constraint (sequencing constraint).

[0042] In a variation of the third example of a buffer storage and load sequencing system, the reciprocating elevator basket includes a single level having one or more load locations.

[0043] There figure 5 illustrates a fourth example of a buffer storage and load sequencing system according to the invention. It differs from the third example illustrated in the figure 4 in that it comprises an output return conveyor CRS, for loads to be returned to the external unit UE. In a variant, there are several output return conveyors, each allowing a return of loads to a particular external unit. The external unit (or each of the external units) is an additional entity to which the control unit UP can organize the third load movements, for the loads returning from the preparation station PP.

[0044] In this example, the CRS output return conveyor and the CRE input return conveyor are positioned at the same height (level referenced as “Level 0”), on either side of the EA alternating elevator. The CAE input forward conveyor and the CRS output return conveyor are parallel and vertically adjacent. In a particular implementation, they have a vertical spacing between them equal to a vertical spacing between two successive levels of the EA alternating elevator basket.

[0045] Thus, several types of returns are possible, making it possible to minimize the use of said at least one external unit and to further improve the responsiveness of the overall system: first returns to the buffer storage units UST1, UST2; second returns to the preparation station PP (via the outgoing forward conveyor); and third returns to the external unit UE, or to at least one other preparation station, or to at least one other external unit (another automated storage / retrieval warehouse, or other buffer storage and load sequencing system).

[0046] In a particular implementation, a portion of the second load movements is performed concurrently with a portion of the third load movements. Similarly, a portion of the third load movements is performed concurrently with a portion of the first load movements.

[0047] For example, the UP control unit is configured to organize, whenever possible: a transfer of first loads from the alternative elevator EA to the buffer storage units UST1, UST2 at the same time as a transfer of second loads from the buffer storage units UST1, UST2 to the alternative elevator EA. Failing this, these two transfers are carried out successively; a transfer of the second loads from the alternative elevator EA to the outward exit conveyor CAS at the same time as a transfer of third loads from the inward return conveyor CRE to the alternative elevator EA. Failing this, these two transfers are carried out successively; a transfer of the third loads from the alternative elevator EA to the outward exit conveyor CRS or the buffer storage units UST1, UST2 at the same time as a transfer of fourth loads from the inward exit conveyor CAE to the alternative elevator EA or the buffer storage units UST1, UST2. Failing this, these two transfers are carried out successively.

[0048] This combination of first, second and third load movements allows the throughput of the buffer storage and sequencing system to be increased.

[0049] In a variation of the fourth example of a buffer storage and load sequencing system, the reciprocating elevator basket comprises a single level having one or more load locations.

[0050] There figure 6 illustrates a fifth example of a buffer storage and load sequencing system according to the invention. It differs from the fourth example illustrated in the figure 5 in that each level 22a, 22b of the single nacelle 21 of the alternative elevator EA comprises a row of two locations. The alternative elevator therefore has a capacity of KxL loads, with K the number of levels and L the number of loads per level (in the example illustrated on the figure 6 , the capacity is 2x2 charges).

[0051] There figure 7 illustrates a sixth example of a buffer storage and load sequencing system according to the invention. It differs from the fifth example illustrated in the figure 6 in that it comprises, between the alternating elevator EA and the outgoing forward conveyor CAS, an outgoing transfer device DTS and an outgoing sequencer SeqS. Furthermore, in this sixth example, the system does not comprise the incoming return conveyor CRE or the outgoing return conveyor CRS. In a variant, it comprises them.

[0052] The output transfer device DTS comprises two levels, each capable of receiving two loads. More generally, it comprises the same number K of levels as the alternative elevator, and each of its levels can receive the same number L of loads as each of the levels of the alternative elevator. Each of the locations of the output transfer device DTS is, for example, equipped with a motorized conveyor section (or any transfer device) for transferring a load onto or off the output transfer device DTS. In a variant, each of these locations is equipped with free rollers, the movement of which is, for example, ensured by a retractable mechanical means positioned at the end of another piece of equipment (conveyor or alternative elevator). Other means of movement may be envisaged. To achieve a simultaneous transfer of a maximum of KxL loads (2x2 loads in the example of the figure 7 ), the K levels of the alternative elevator EA are aligned with the K levels of the output transfer device DTS.

[0053] The SeqS output sequencer is provided with vertical movement means. It is capable of transferring loads between the DTS output transfer device and the CAS output forward conveyor. The SeqS output sequencer is a lifting table type device with a platform, or any other equivalent device that allows the vertical movement of a load. In this example, the SeqS output sequencer comprises a single level (i.e. a single platform) which is equipped with a motorized conveyor portion allowing the horizontal movement of a load.

[0054] The UP control unit is configured to control: a transfer of a group of N loads, from the buffer storage units UST1, UST2 to the alternative elevator EA, with N less than or equal to a capacity C of the alternative elevator EA in number of loads (C=KxL). For each group of N loads, the sequencing of the loads placed at each level of the alternative elevator is consistent with the delivery constraint (sequencing constraint on the outbound conveyor CAS).Thus, the sequencing of the loads on each level of the alternating elevator (sequencing which is retained on each level of the output transfer device) makes it possible to simplify the sequencing function carried out by the output sequencer; a transfer, simultaneously on the K levels, of each group of N loads from the alternating elevator EA to the output transfer device DTS; and a transfer of each group of N loads, via the output sequencer SeqS, from the output transfer device DTS to the output forward conveyor CAS, under the delivery constraint (sequencing constraint).

[0055] In this sixth example, for the transfer of loads from the alternative elevator EA to the preparation station PP, the alternative elevator is therefore used in combination with two other elements: an output transfer device DTS, which provides an additional buffer function, allowing a group of N loads to be put on hold, after their unloading by the alternating elevator; and an output sequencer SeqS, which participates in carrying out the sequencing function.

[0056] This combination of three elements makes it possible to significantly increase the overall throughput of the buffer storage and sequencing system, while respecting sequencing constraints.

[0057] In a variant, the output transfer device DTS is provided with vertical movement means (alternative elevator type means with platform, or any other equivalent means allowing the vertical movement of loads between two or more levels) and replaces the output sequencer SeqS. This variant is therefore more compact and allows the necessary equipment to be reduced. The control unit UP is configured to control a transfer of each group of N loads directly from the output transfer device DTS to the output forward conveyor CAS. For example, the high level of the output transfer device DTS aligns horizontally with the output forward conveyor CAS, to unload two loads (for example "e" and "f"), then the low level of the output transfer device DTS aligns horizontally with the output forward conveyor CAS, to unload two other loads (for example "g" and "h"), thus respecting the sequence.

[0058] There figure 8 illustrates a seventh example of a buffer storage and load sequencing system according to the invention. It differs from the sixth example illustrated in the figure 7 in that it comprises, between the input forward conveyor CAE and the alternative elevator EA, an input transfer device DTE and an input sequencer SeqE.

[0059] The DTE input transfer device comprises two levels, each capable of receiving two loads. More generally, it comprises the same number K of levels as the alternative elevator, and each of its levels can receive the same number L of loads as each of the levels of the alternative elevator. Each of the locations of the DTE input transfer device is, for example, equipped with a motorized conveyor section (or any other transfer device) for transferring a load onto or off the DTE input transfer device. In a variant, each of these locations is equipped with free rollers, the movement of which is, for example, ensured by a retractable mechanical means positioned at the end of another piece of equipment (conveyor or alternative elevator). Other means of movement may be envisaged. To achieve a simultaneous transfer of a maximum of KxL loads (2x2 loads in the example of the figure 8 ), the K levels of the alternative booster EA are aligned with the K levels of the input transfer device DTE.

[0060] The SeqE input sequencer is provided with vertical movement means. It is capable of transferring loads between the CAE input forward conveyor and the DTE input transfer device. The SeqE input sequencer is a lifting table type device with a platform, or any other equivalent device that allows the vertical movement of a load. In this example, the SeqE input sequencer comprises a single level (i.e. a single platform) which is equipped with a portion of motorized conveyor allowing the horizontal movement of a load.

[0061] The UP control unit is configured to control: a transfer of loads, via the input sequencer SeqE, from the input forward conveyor CAE to the input transfer device DTE, by forming in the input transfer device groups of N' loads distributed over the different levels, with N' less than or equal to the capacity C of the alternating elevator in number of loads (C=KxL). For each group of N' loads, the sequencing of the loads placed at each level of the input transfer device DTE is consistent with a constraint of depositing the N' loads in the buffer storage units UST1, UST2.Thus, the sequencing of the loads on each level of the input transfer device DTE (sequencing which is kept on each level of the alternating elevator) makes it possible to simplify the realization of the constraint of depositing the N' loads (in the buffer storage units); a transfer, simultaneously on the K levels, of each group of N' loads from the input transfer device DTE to the alternating elevator; and a transfer of each group of N' loads, from the alternating elevator to the buffer storage units UST1, UST2, under the constraint of depositing the N' loads.

[0062] In this seventh example, for the transfer of loads from the external unit UE to the alternative elevator EA, the alternative elevator is therefore used in combination with two other elements: an input transfer device DTE, which provides an additional buffer function, allowing a group of N loads to be put on hold, before their loading onto the alternating elevator, which is also multi-level; and an input sequencer SeqE, which allows loads to be transferred in a determined order to the input transfer device DTE.

[0063] This combination of three elements makes it possible to optimize the general rate of the buffer storage and sequencing system, while respecting the constraints of placing the loads in the UST1, UST2 buffer storage units.

[0064] In one variant, the input transfer device DTE is provided with vertical movement means (alternative elevator type means with platform, or any other equivalent means allowing the vertical movement of loads between two or more levels) and replaces the input sequencer SeqE. This variant is therefore more compact and makes it possible to reduce the necessary equipment. The control unit UP is configured to control a transfer of each group of N' loads directly from the input forward conveyor CAE to the input transfer device DTE. For example, the low level of the input transfer device DTE aligns horizontally with the input forward conveyor CAE, to load a load (for example "a"), then the high level of the input transfer device DTE aligns horizontally with the input forward conveyor CAE, to unload another load (for example "b"), etc.

[0065] There figure 9 illustrates an eighth example of a buffer storage and load sequencing system according to the invention. It differs from the seventh example illustrated in the figure 8 in that each level of each of the two buffer storage units UST1, UST2 is multi-load, i.e. comprises several (for example three) buffer locations.

[0066] THE figures 10a, 10b et 10c illustrate a ninth example of a buffer storage and load sequencing system according to the invention. It differs from the fifth example illustrated in the figure 6 in that the input forward conveyor CAE and the output return conveyor CRS are positioned at the same height (level referenced “Level 2”), on either side of the alternative elevator EA.

[0067] THE figures 11a, 11b et 11c illustrate a tenth example of a buffer storage and load sequencing system according to the invention. It differs from the ninth example illustrated in the figures 10a, 10b and 10c in that the input forward conveyor CAE and the output return conveyor CRS are parallel and vertically adjacent. In a particular implementation, they have a vertical spacing between them equal to a vertical spacing between two successive levels of the nacelle of the alternative elevator EA. In this example, the input forward conveyor CAE is positioned at a height (level referenced “Level 3”) higher than that (level referenced “Level 2”) of the output return conveyor CRS.

[0068] THE figures 12a, 12b et 12c illustrate an eleventh example of a buffer storage and load sequencing system according to the invention. It differs from the ninth example illustrated in the figures 10a, 10b and 10c in that: The alternative lift platform includes a single level with two rows of two load locations. On the figure 12b (top view), one row contains the loads “a” and “b”, and the other row the loads “i” and “j”; the CAS outbound conveyor and the CRE inbound return conveyor are parallel, horizontally adjacent (at the level referenced “Level 0”) and have between them a horizontal spacing equal to a horizontal spacing between the two rows of the single level of the nacelle of the alternative elevator EA.The positioning of these conveyors CAS and CRE relative to the alternative elevator EA is such that it is possible to simultaneously transfer loads on the one hand between the outgoing feed conveyor CAS and one of the two rows of the single level of the nacelle of the alternative elevator EA, and on the other hand between the inlet return conveyor CRE and the other of the two rows of the single level of the nacelle of the alternative elevator EA; the outgoing feed conveyor CAE and the outgoing return conveyor CRS are parallel, horizontally adjacent (at the level referenced “Level 1”) and have between them a horizontal spacing equal to a horizontal spacing between the two rows of the single level of the nacelle of the alternative elevator EA.The positioning of these CAE and CRS conveyors relative to the EA alternating elevator is such that it is possible to simultaneously transfer loads on the one hand between the CAE inlet forward conveyor and one of the two rows of the single level of the nacelle of the EA alternating elevator, and on the other hand between the CRS outlet return conveyor and the other of the two rows of the single level of the nacelle of the EA alternating elevator.

[0069] THE figures 13a, 13b et 13c illustrate a twelfth example of a buffer storage and load sequencing system according to the invention. It differs from the eleventh example illustrated in the figures 12a, 12b et 12c in that the nacelle of the alternative elevator comprises K levels, with K ≥ 2 (in the example illustrated in the figures 13a, 13b et 13c , on a K=2), each comprising two rows of two charge locations. On the figure 13b (top view), the upper level of the reciprocating elevator basket comprises a first row, which contains the loads "c" and "d", and a second row, which contains the loads "i" and "j". As partially visible on the figure 13b (side view), the low level of the reciprocating elevator basket comprises a first row, which contains loads "a" and "b", and a second row, which contains loads "k" and "1".

[0070] The twelfth example also illustrates the possibility that the system comprises one or more pairs of additional conveyors, each associating an input forward conveyor and an output return conveyor, and allowing exchanges (forward and return) of loads with another external unit (not shown). This other external unit is for example an automated storage / retrieval warehouse or another buffer storage and load sequencing system.

[0071] So, on the figures 13a, 13b et 13c , the system comprises a first pair of additional conveyors denoted CAE' and CRS', positioned at the level referenced "Level 1", and a second pair of additional conveyors denoted CAE" and CRS", positioned at the level referenced "Level 2".

[0072] The configuration of each of the ninth, tenth, eleventh and twelfth examples makes it possible to combine the return of loads from the PP preparation station to the CRS output return conveyor(s) (CRS', CRS") or the UST1, UST2 buffer storage units, with minimal disruption to the flow of sequenced loads on the CAS output forward conveyor.

[0073] There figure 14 presents an example of the structure of the aforementioned UP control unit, according to a particular embodiment of the invention. The UP control unit comprises a random access memory 143 (for example a RAM memory), a processing unit 141, equipped for example with a processor, and controlled by a computer program stored in a read-only memory 142 (for example a ROM memory or a hard disk). Upon initialization, the code instructions of the computer program are for example loaded into the random access memory 143 before being executed by the processor of the processing unit 141. The processing unit 141 receives input signals 44, processes them and generates output signals 45.

[0074] The input signals 144 include various information relating to the operation of the overall system (including in particular the external unit(s), the buffer storage and sequencing system and the preparation station(s), in particular the load identifiers read (by reading devices such as barcode readers, RFID tag readers, etc.) on the loads when they pass through different locations in the overall system (for example at the ends of the different conveyors).

[0075] The output signals 145 include various control information for the piloting (control) of the equipment of the overall system (in particular within the buffer storage and sequencing system), in order to manage the movements of the loads in the overall system.

[0076] This figure 14illustrates only one particular implementation among several possible ones. Indeed, the UP control unit is implemented indifferently on a reprogrammable computing machine (a PC computer, a DSP processor or a microcontroller) executing a program comprising a sequence of instructions, and / or on a dedicated computing machine (for example a set of logic gates such as an FPGA or an ASIC, or any other hardware module). In the case where the control unit is implemented at least in part on a reprogrammable computing machine, the corresponding program (i.e. the sequence of instructions) may be stored in a removable storage medium (such as for example a floppy disk, a CD-ROM or a DVD-ROM) or not, this storage medium being partially or totally readable by a computer or a processor.

Claims

1. System of buffer storage and sequencing of loads configured to receive non-sequenced loads coming from at least one external unit (UE) through at least one inbound forward conveyor (CAE, CAE', CAE") included in said system and to provide sequenced loads to at least one preparing station (PP, PP'), through at least one outbound forward conveyor (CAS, CAS') included in said system, said system being characterized in that it comprises: - a reciprocating lift (EA) comprising a single nacelle comprising K levels each enabling the transportation of at least one load, with K ≥ 2; - at least one buffer storage unit (UST1, UST2) comprising a plurality of buffer locations distributed over a plurality of levels and each configured to temporarily receive at least one load coming from the reciprocating lift; and - a managing unit (UP) configured to organize: * first movements of loads from said at least one inbound forward conveyor (CAE, CAE', CAE") to said at least one buffer storage unit (UST1, UST2), through the reciprocating lift (EA); and; * second movements of loads from said at least one buffer storage unit (UST1, UST2) to said at least one outbound forward conveyor (CAS, CAS'), through the reciprocating lift (EA), under a constraint of delivery, on said at least one outbound forward conveyor (CAS, CAS'), of at least one sequence comprising loads in a given sequential order by means of said reciprocating lift, characterized in that the managing unit (UP) is configured to furthermore organize third movements of loads through the reciprocating lift (EA), for loads that have been treated by said at least one preparing station (PP), from at least one inbound return conveyor (CRE), included in said system, towards at least one of the entities belonging to the group comprising: - said at least one buffer storage unit (UST1, UST2) for loads that have to be stored again; - said at least one outbound forward conveyor (CAS, CAS') for loads having to be again presented to said at least one preparing station (PP), under said constraint of delivery; and - at least one outbound return conveyor (CRS, CRS', CRS") included in said system, for loads that have to be sent back to at least one of the entities belonging to the group comprising said at least one external unit (UE), at least one other preparing station and at least one other external unit, and in that the system comprises, between the reciprocating lift (EA) and said at least one outbound forward conveyor (CAS, CAS'): - an outbound transfer device (DTS) comprising K levels enabling each one to receive at least one load; and - an outbound sequencer (SeqS) provided with vertical shifting means; and in that the managing unit (UP) is configured to manage: - a transfer of a group of N loads from at least one buffer storage unit (UST1, UST2) towards the reciprocating lift (EA) with N being smaller than or equal to a capacity of the reciprocating lift (EA) in number of loads; - a transfer, simultaneously on all K levels, of each group of N loads from the reciprocating lift EA to the outbound transfer device (DTS); and - a transfer of each group of N loads, through the outbound sequencer SeqS, from the outbound transfer device (DTS) to said at least one outbound forward conveyor (CAS) under delivery constraint.

2. System according to claim 1, characterized in that a part of the first movements of loads is carried out at the same time as a part of the second movements of loads.

3. System according to any one of the claims 1 and 2, characterized in that a part of the second movements of loads is carried out at same time as a part of a third movements of loads and in that a part of the third movements of loads is carried out at same time as a part of the first movements of loads.

4. System according to any one of the claims 1 to 3, characterized in that each of the K levels of the nacelle of the reciprocating lift (EA) comprises a row of at least two load locations, and in that the system comprises at least one pair comprising an outbound forward conveyor (CAS, CAS') and an inbound return conveyor (CRE) that are parallel and vertically adjacent.

5. System according to any one of the claims 1 to 3, characterized in that each of the K levels of the nacelle of the reciprocating lift (EA) comprises two rows of at least two load locations, and in that the system comprises at least one pair comprising an outbound forward conveyor (CAS, CAS') and an inbound return conveyor (CRE) that are parallel and vertically adjacent and have a horizontal distance between them equal to a horizontal distance between two rows of each of the K levels of the nacelle of the reciprocating lift (EA).

6. System according to any one of the claims 1 to 3, characterized in that each of the K levels of the nacelle of the reciprocating lift (EA) comprises a row of at least two load locations, and in that the system comprises at least one pair comprising an inbound forward conveyor (CAE) and an outbound return conveyor (CRS) that are parallel and vertically adjacent.

7. System according to any one of the claims 1 to 3, characterized in that each of the K levels of the nacelle of the reciprocating lift (EA) comprises a row of at least two load locations, and in that the system comprises at least one pair comprising an inbound forward conveyor (CAE) and an outbound return conveyor (CRS) that are positioned at a same height on either side of the reciprocating lift (EA).

8. System according to any one of the claims 1 to 3, characterized in that each of the K levels of the nacelle of the reciprocating lift (EA) comprises two rows of at least two load locations, and in that that the system comprises at least one pair comprising an inbound forward conveyor (CAE, CAE', CAE") and an outbound return conveyor (CRS, CRS', CRS") that are parallel, horizontally adjacent and have a horizontal distance between them equal to a horizontal distance between two rows of each of the K levels of the nacelle of the reciprocating lift (EA).

9. System according to any one of the claims 1 to 8, characterized in that it comprises two buffer storage units (UST1, UST2) disposed vertically on either side of the reciprocating lift (EA) and each comprising a plurality of levels each comprising at least one buffer location, each of the K levels of the nacelle of the reciprocating lift (EA) being able to come into a position facing each of the levels of each of the buffer storage units (UST1, UST2) for a transfer of at least one load.

10. System according to any one of the claims 1 to 9, characterized in that the outbound transfer device (DTS) is provided with vertical shifting means and replaces the output sequencer SeqS and in that the managing unit UP is configured to manage a transfer of each group of N loads directly from the outbound transfer device (DTS) to the outbound forward conveyor (CAS, CAS').

11. System according to any one of the claims 1 to 110, characterized in that the reciprocating lift (EA) is a multi-load lift at each level, and in that the managing unit (UP) is configured to manage, for each group of N loads, a sequencing of the loads placed at each level of the reciprocating lift, said sequencing being consistent with said delivery constraint.

12. System according to any one of the claims 1 to 11, characterized in that it comprises, between said at least one inbound forward conveyor (CAE, CAE', CAE") and the reciprocating lift (EA): - an inbound transfer device (DTE) comprising K levels enabling each to receive at least one load; and - an inbound sequencer (SeqE) provided with vertical shifting means; and in that the managing unit (UP) is configured to manage: - a transfer of loads, via the incoming sequencer, from said at least one incoming forward conveyor (CAE, CAE', CAE") towards the incoming transfer device (DTE), in forming, in the inbound transfer device, groups of N' loads distributed over the K levels, with N' smaller than or equal to a capacity of the reciprocating lift in number of loads; - a transfer, simultaneously on the K levels, of each group of N' loads from the incoming transfer device (DTE) to the reciprocating lift; and - a transfer of each group of N' loads, from the reciprocating lift to said at least one buffer storage unit (UST1, UST2), under a constraint of deposition of the N' loads.

13. System according to claim 12, characterized in that incoming transfer device (DTE) is provided with vertical shifting means and replaces the incoming sequencer (SeqE), and in that the managing unit (UP) is configured to manage a transfer of each group of N' loads directly from said at least one incoming forward conveyor (CAE, CAE', CAE") to the incoming transfer device.

14. System according to any one of the claims 12 and 13, characterized in that characterized in that the reciprocating lift (EA) is a multi-load lift at each level, and in that the managing unit (UP) is configured to manage, for each group of N loads,, a sequencing by the incoming sequencer of the loads placed at each level of the incoming transfer device, said sequencing being consistent with said constraint of deposition of the N loads.