FR3139809A1 - TRANSLATION DEVICE FOR MODULAR SYSTEM FOR MOVING STORAGE ELEMENTS - Google Patents

Abstract

The invention relates to a translation device (400) for a modular system for moving storage elements, said system comprising a plurality of adjacent modules (110) and at least one storage rack (300) capable of being moved from a module to an adjacent module, the device (400) comprising a translation mechanism (410) comprising a projecting drive finger (407) intended to cooperate with at least one complementary imprint (301) of the locker (300) to move said locker in translation. The translation mechanism (410) comprises a motorized endless screw (401) mounted to rotate between two bearings (402, 403), as well as a nut (406) cooperating with the screw (401) and carrying the drive finger (407), said device further comprising a Maltese cross indexing mechanism (420) adapted to transmit to the driving finger (407) indexing in at least two stable angular positions, at least one of which is disengaged. Figure for abstract: Figure 2

Description

TRANSLATION DEVICE FOR MODULAR SYSTEM FOR MOVING STORAGE ELEMENTS

The invention relates to the field of automated storage solutions and more precisely to the guidance and indexing means allowing the movement of storage elements in a robotic structure.

STATE OF THE ART

With the rise of industrial needs, fine logistics and e-Commerce, the development and use of automated storage and goods collection solutions are proving decisive for many players. Different types of solutions have been proposed depending on the type of needs they address.

It is known, for example, to use technologies of the “Stack crane” type or the “Carousel” type or the “Robotic fleet” type or the implementation of autonomous and mobile robots. These technologies differ in their nature but also in their performance, and are therefore not suitable for the same uses. In addition, they do not allow a compact storage solution, adaptable to any type of space, particularly restricted ones, and presenting a high distribution rate while limiting the need for manual intervention and thus facilitating its use.

The applicant's patent application WO2020260639 offers a compact storage and movement solution, adaptable to any type of storage environment and allowing high distribution rates. The system which is described in this application comprises on the one hand a modular structure made up of a plurality of adjacent reception modules and on the other hand lockers capable of being moved in the modular structure from one module to another.

In order to ensure this movement, the modules are equipped with actuators which cooperate with complementary imprints carried by the lockers. These actuators are attached to the frame bars of the structure. The cooperation of an actuator with the imprint(s) of a locker makes it possible to drive said locker in translation so that it passes from one module to an adjacent module. The system also includes a central controller, configured to control the actuators and manage the movement of the lockers.

One aim of the invention is to further improve the solution proposed in the aforementioned application.

In particular, it offers a solution which allows cooperation between the impressions and the actuators of greater robustness, while allowing great precision and movement efficiency.

To this end, the invention proposes a translation device for a modular system for moving storage elements, said system comprising a plurality of adjacent modules and at least one storage locker capable of being moved from one module to another module. adjacent, the device comprising a translation mechanism comprising a projecting drive finger intended to cooperate with at least one complementary imprint of the rack to move said rack in translation. The translation mechanism comprises an endless screw (motorized mounted in rotation between two bearings, as well as a nut cooperating with the screw and carrying the drive finger, said device further comprising an indexing mechanism adapted to transmit to the finger training indexing on at least two stable angular positions (preferably three, or even more), one which is a disengaged position, the other which is a position in which the finger is able to cooperate with a complementary imprint of the locker to ensure its training.

In this way it is possible to translate the driving finger with great precision of movement along the screw and according to several different angular positions (disengaged or engaged) of the driving finger. The translation movement can be initiated regardless of the starting position of the drive element.

The indexing mechanism is advantageously a Maltese cross mechanism.

In particular, for example, this Maltese cross mechanism includes:

- a Maltese cross driven wheel which is mounted, with the bearings which carry the endless screw, on an upright of a module, said driven wheel being coaxial with the endless screw, said endless screw and the wheel being suitable to rotate relative to each other,

- a motorized crank mounted on the upright and capable of moving the Maltese cross driven wheel between several positions

- at least one guide bar, in particular two (or more) which extends parallel to the endless screw, said guide bar being fixed relative to the Maltese cross driven wheel and in sliding connection relative to the nut.

The translation of the driving finger along the screw is facilitated by blocking the rotation of the nut by means of the guide bar(s), which makes it possible to eliminate any possible torques on the driving finger.

The device may include at least one brake which is adapted to block the endless screw when said motor is not actuated

According to yet another aspect, the invention relates to a modular system for moving storage elements comprising a plurality of adjacent modules and at least one storage compartment capable of being moved in the modular structure from one module to an adjacent module, a module comprising a chassis (210) comprising uprights, at least one upright carrying a translation device of the aforementioned type.

Such an amount can be an open profile.

It may include support plates attached near its ends, the translation device being fixed in a removable manner between these plates.

Installation and maintenance are then made easier.

PRESENTATION OF FIGURES

Other characteristics, aims and advantages of the invention will emerge from the description which follows, which is purely illustrative and not limiting, and which must be read with reference to the appended drawings in which:

- there illustrates a perspective view of a part of a robotic system according to one embodiment;

- there illustrates a perspective view of a translation device according to one embodiment;

- THEFigures 3A, 3B and 3Cillustrate different parts of a translation device according to one embodiment;

- THEFigures 4A, 4B and 4Cillustrate steps of a method of releasing a translation device according to one embodiment;

- THEFigures 5A and 5Billustrate different views of an imprint of a locker of the robotic system according to one embodiment;

- there illustrates a perspective view of the cooperation between a translation device and a module according to one embodiment;

- THEFigures 7A and 7Billustrate different orientations of the nut of the devicetranslation according to one embodiment;

- THEFigures 8A, 8B, 8C and 8Dillustrate the changes in position of a Maltese cross under the effect of a crank according to one embodiment;

- there illustrates a view of several stable positions of the Maltese cross according to one embodiment;

- THEFigures 10A, 10B, 10C, 10D, 10E and 10Fillustrate steps of a method of translating a locker in a robotic structure by means of a translation device according to one embodiment.

In all the figures, similar elements bear identical references.

DETAILED DESCRIPTION

General information on the movement and storage system

The system 100 for moving storage elements illustrated on the comprises a modular structure 200, typically placed on the floor of a storage room, and one or more lockers 300 intended to be moved inside said structure 200.

The modular structure 200 is defined by a plurality of adjacent reception modules 110. These modules 110 are juxtaposed, stacked and connected together to form the modular structure 200. To simplify understanding, only one rack 300 and two reception modules 110 have been represented on the .

The modularity of the structure 200 thus allows adaptation to any environment; it also facilitates and streamlines the flow of goods between the delivery point(s) and the goods collection point(s).

More particularly, the structure 200 is defined by a plurality of vertical uprights 111 and horizontal bars 112 assembled during the installation of said structure 200, which can be dismantled or modified easily.

Said uprights 111 and bars 112 thus define for each module 110 a chassis which is typically of rectangular parallelepiped shape and which defines a reception volume adapted to receive a locker 300.

The lockers 300 are of dimensions and shape (in this case, rectangular parallelepiped) allowing them to be received in the modules 110. They each include for example a bottom and a frame which together form an enclosure capable of receiving and carrying a content to store. In the embodiment shown, the enclosure has open side faces, which improves accessibility for a user.

The uprights 111 carry devices 400 which cooperate with imprints 301 on the racks 300 to ensure movement in a first direction (in the example illustrated, the vertical direction). The bars 112 carry actuators 250 which cooperate with other imprints of the racks 300 and ensure movement in a second direction which is perpendicular to the first (in the example, the horizontal direction). These devices 400 and 250 are connected, by wired cabling which runs along the bars, to a control unit (not shown) which manages the movements of the lockers 300 and activates these devices accordingly.

The horizontal actuators 250 are typically actuators with horizontal translators described in application WO2020260639 to which reference can advantageously be made.

The translation devices 400 are integrated along the uprights 111 which extend in the first direction (vertical direction in the example). In the case of a parallelepiped module 110, each module 110 thus comprises four translation devices 400 integrated into the four uprights 111 which define the chassis of a module.

Translation device 400

• un mécanisme 410 à vis sans fin qui assure le déplacement en translation d’un doigt 407 destiné à s’engager dans une empreinte complémentaire 301 d’un casier 300 ( ) pour entrainer ledit casier dans son déplacement vertical
• un mécanisme d’indexation 420 configuré pour pouvoir embrayer ou débrayer le mécanisme de translation 410, dans des positions précises .

A device 400 as illustrated on the and detailed on thefigures 3A, 3B and 3Ccombines:

• a worm screw mechanism 410 which ensures the translational movement of a finger 407 intended to engage in a complementary imprint 301 of a locker 300 ( ) to drive said locker in its vertical movement
• an indexing mechanism 420 configured to be able to engage or disengage the translation mechanism 410, in precise positions.

Such a device 400 is mounted on an open profile which defines an upright 111, inside said upright.

410 translation drive mechanism

The translation drive mechanism 410 comprises an endless screw 401 mounted in rotation between two bearings 402 ( ) and 403 ( ), as well as a nut 406 which cooperates with the screw 401 and on which the drive finger 407 is mounted ( ). In the example shown, bearing 402 is a lower bearing, while bearing 403 is an upper bearing mounted on a vertical upright. Throughout this text, the terms “lower” and “upper” are defined according to the vertical direction.

The two bearings 402 and 403 are fixed on support plates 201 and 202 which the upright 111 presents in the vicinity of its two ends.

The translation drive mechanism 410 further comprises an electric motor 404 ( ), which drives the screw 401 by means of a coupling 405.

This motor 404 is also housed in the upright 111. It is positioned at one end of the screw 401, for example under the fixing support plate 201 which is located at the lower end of the upright 111.

Such a drive system makes it possible to precisely and robustly control the movement of the nut 406. The precision can be improved by reducing the pitch of the screw 401.

In addition, it is possible to couple a brake 408 to the motor 404 (for example a shoe brake) in order to make the screw 401 irreversible when said motor 404 is not actuated and therefore to allow a stable position of the nut 406 without impact the performance of screw 401.

420 indexing mechanism

The indexing mechanism 420 comprises a Maltese cross type device 412 ("Geneva Cross" according to Anglo-Saxon terminology) whose driven wheel 413 is rotatably mounted on the support plate 201. Said wheel 413 and the screw 401 driven by the motor 404 are coaxial, the screw 401 being free to rotate relative to said Maltese cross wheel 413.

The Maltese cross device 412 further comprises a crank 414 mounted to rotate on the support plate 201 along an axis offset relative to that of the wheel 413.

It further comprises one or more guide bars 411 fixed to the Maltese cross 412 and adapted to transmit the indexing of the Maltese cross 413 to the drive finger 407 of the translation mechanism 410.

The guide bar(s) 411 extend parallel to the endless screw 401 while being fixed on the driven wheel 413.

The use of two 411 guide bars (or more) makes it possible to balance the forces and increase the rigidity.

The finger 407 of the translation mechanism 410 is crossed by the guide bars 411 fixed on the wheel 413 of the Maltese cross device 412. These guide bars 411 make it possible to index the angular position of the finger 407 to that of the cross of malta 412.

The crank 414 is adapted to rotate the wheel 413 of the Maltese cross 412. It is for this purpose driven by an electric motor 415.

Thus, the angular positioning of the finger 407 is controlled by the indexing mechanism 420 which allows robust, stable and precise positioning.

Plain bearings 411a can be provided between the projecting finger 407 and the guide bars 411 in order to facilitate sliding and prevent bracing between these two elements.

In another embodiment, ball bushings or any other translational guide element could be mounted between the finger 407 and the guide bars 411 so as to facilitate sliding and prevent bracing.

Mounting finger 407 on nut 406

The finger 407 is linked to the nut 406 so that on the one hand the translation movement of the nut 406 is transmitted to said finger 407 and on the other hand the rotation of the nut 406 is blocked by the finger d drive 407, this being in slide connection with the indexing system 420.

Preferably, the finger 407 and the nut 406 are linked by an engagement. Subsequently we will talk about the translation movement of the nut 406 and/or the position and/or the orientation of the finger 407, the translation and/or orientation of one implying that of the other and reciprocally.

Assembly/disassembly of a device 400 in an amount 111

Advantageously, and as illustrated by Figures 4A, 4B and 4C , the two bearings 402 and 403 are fixed in a removable manner to the support plates 201 and 202 themselves fixed on the upright 111 of the structure 200. Thus, the device translation 400 can be removed from an upright 111 by very easy disassembly.

The fixing of the bearings 402 and 403 on the support plates 201 and 202 is for example ensured by angular retaining screws 409, 410/

During disassembly, these angular retaining screws 409 and 410 are, initially, loosened ( ). Then, the endless screw 401 and the bearings 402 and 403 are raised to be disengaged from the lower and upper plates 201 and 202 respectively. Finally, the bearings 402 and 403 are rotated, here in a clockwise direction, in order to remove the endless screw. end 401 and the bearings 402 and 403 by opening the profile of the upright 111 and allow the total release of the translation device 400 from the modular structure 200.

Footprint 301

Figures 5A and 5B illustrate a vertical imprint 301 attached to the vertical edges of the frame of a locker 300 by means of a fixing rim 303 projecting relative to said chassis 300. The vertical imprint 301 has ( ) an opening with two inclined sides 350 together defining a drain intended to receive the finger 407. These two inclined sides 350 are extended inside the cavity 301 by two straight vertical sides 351 between which the walls of the finger are positioned 407. The finger 407 is of complementary shape, the inclined sides 350 making it possible to guide and center the finger 407 between said straight sides 351 in order to limit the movement of the locker 300 during the vertical translation movement.

The imprint 301 also includes a horizontal wall 352 which closes the right sides 350 and corresponds to the contact zone between the finger 407 and the imprint 301 when the locker 300 is driven during a vertical translation movement by the finger 407 which then abuts against the horizontal side 352.

There illustrates the translation device 400 about to engage with the rack 300. The finger 407 is then between the two inclined sides 350 and will be inserted between the two straight sides 351 to abut against the horizontal side 352 of the imprint 301 of the locker 300.

According to one embodiment, a locker 300 of the robotic system 100 comprises on each of these vertical edges an imprint 301 and preferably two. Advantageously, on each vertical edge, an imprint 301 is positioned on a lower half of the edge and the other imprint 301 is positioned on a high half of the edge. And advantageously the imprints of the same edge are as far away from each other as possible.

Example of indexing

The Maltese cross 412 allows you to define stable angular positions and unstable intermediate angular positions. The stable angular positions are the positions in which the Maltese cross 412 is blocked in rotation by the crank 414. The unstable angular positions are the angular positions that the Maltese cross 412 can take during a rotational movement between two stable positions . The position of the Maltese cross 412 varies thanks to the crank 414 rotatably mounted on the chassis and driven by the motor 415.

According to an embodiment explained by Figures 7A and 7B , the Maltese cross 412 of the indexing system 420 makes it possible to position the nut 406 of the translation mechanism 410, in this case in three stable positions, only two stable positions being represented in the figures.

The finger 407 is in the disengaged position 455 ( ) or in engaged position 454 ( ) with the imprint 301 of the locker 300 of the robotic system 100. More precisely, a “training position” or engaged position 454 is defined as being a position of the finger 407 for which the projection of the finger 407 and the projection of the imprint 301 vertical in a horizontal plane have an intersection in the horizontal plane. And we define a “non-training” or disengaged position 455 as being a position for which the projection of the finger 407 and the projection of the vertical imprint 301 in a horizontal plane does not present any intersection. Subsequently, we will use the term engaged position 454 and disengaged position 455 to talk about the training and non-training positions.

Indeed, a minimum of two stable angular positions is necessary in order to be able to allow the finger 407 to cooperate with vertical imprints 301 in the case of a vertical translation movement on the one hand, and to retract the finger 407 in a disengaged position 455 during a horizontal translation movement on the other hand.

In the case of three positions, one of these positions can be a disengaged position where the finger 407 is disengaged vertically and where the locker can be driven in a horizontal direction, another is a position where the finger 407 is disengaged vertically and where the locker can be driven in a horizontal direction perpendicular to the previous one, another finally being an engaged position for the vertical movement of the locker.

• la roue menée 413 de la croix de malte 412 étant dans une position stable quelconque, la face cylindrique 450 de la manivelle 414 est logée dans une rainure cylindrique 451 complémentaire de la roue menée 413;
• la manivelle 414 est mise en rotation par exemple dans le sens horaire, et cela a pour effet de réduire le contact entre la face cylindrique 450 de la manivelle 414 et une des rainures cylindriques 451 présentes sur le pourtour de la roue menée 413 et d’initier le glissement du maneton 452 de la manivelle 414 dans une saignée 453 de la roue menée 413 impliquant une rotation dans le sens anti-horaire de la roue menée 413 ( ) ;
• la rotation de la manivelle 414 continue jusqu’à ce que la face cylindrique 450 de la manivelle 414 se retrouve de nouveau concentrique avec une autre des rainures cylindriques 451 présentent sur le pourtour de la roue menée 413 ( ).

The crank 414 advantageously has a cylindrical face 450 and a crankpin 452. The cylindrical face 450 and the crankpin 452 cooperate to rotate the cross of my. Indexing, that is to say the change in angular position of the Maltese cross 412 carried out by the crank 414 (illustrated by Figures 8A, 8B, 8C and 8D ), is, for example implemented by the following steps :

• the driven wheel 413 of the Maltese cross 412 being in any stable position, the cylindrical face 450 of the crank 414 is housed in a cylindrical groove 451 complementary to the driven wheel 413;
• the crank 414 is rotated for example in a clockwise direction, and this has the effect of reducing the contact between the cylindrical face 450 of the crank 414 and one of the cylindrical grooves 451 present on the periphery of the driven wheel 413 and of initiate the sliding of the crankpin 452 of the crank 414 in a groove 453 of the driven wheel 413 involving a counterclockwise rotation of the driven wheel 413 ( ) ;
• the rotation of the crank 414 continues until the cylindrical face 450 of the crank 414 finds itself concentric again with another of the cylindrical grooves 451 present on the periphery of the driven wheel 413 ( ).

The Maltese cross 412 is said to be in a stable position when the cylindrical face 450 of the crank 414 is housed in a cylindrical groove 451 of the driven wheel 413.

Thus this indexing allows an advantageous, precise and stable definition of the different angular positions of the finger 407 thanks to a continuous rotation of the crank 414.

According to one embodiment, the Maltese cross 412 has more than two cylindrical grooves 451 allowing more than two stable positions. For example, and as illustrated by , the Maltese cross 412 preferably has three stable positions, one of which is an engaged position 454. The angular positions of the finger 407 are indicated in the dashed lines. The central position is an engaged position 454 and the extreme positions are disengaged positions 455. In this embodiment, the disengaged positions 455 are disoriented by 45° on either side of the engaged position 454. In this way, the finger 407 in the disengaged position 455 is arranged parallel to an edge of the locker 300 and is not likely to collide with it during a step which is not a step of vertical translation of the locker 300 operated by the finger 407.

Thus, during operation, when the finger 407 is in a stable angular position during the translation phases, that is to say it is blocked in its rotational movement by the guide bars 411 and moves in vertical translation by means of the helical connection between the screw 401 and the nut 406. In this way, each finger 407 is either in the engaged position 454 with an imprint of the locker or disengaged 455 which is a stable position and avoiding any contact with the locker.

The vertical translation can be upward or downward depending on the direction of rotation of the screw 401. The direction of upward rotation of the screw 401 is defined as the direction of rotation driving the nut 406, locked in rotation, in vertical upward translation. Likewise, we define the direction of downward rotation of the screw 401 as the direction driving the nut 406, blocked in rotation, in downward vertical translation. By descending we mean a movement which goes towards the ground on which the robotic system 100 rests and by ascending a movement which moves away from it. In this way, when the screw 401 is driven in upward rotation and the finger 407 is in the engaged position 454, the finger 407 can cooperate with the vertical imprint 301 by coming into contact with the horizontal side 352 in order to drive the locker 300 when of an upward vertical translation movement.

Translation of a locker into a modular structure

• Les doigts 407 des huit dispositifs de translation 400 des modules inférieur 110a et supérieur 110b sont orientés dans une position stable à une hauteur quelconque et le casier 300 repose sur un actionneur horizontal du module inférieur 110a de la structure modulaire 200.
• Les vis 401 des mécanismes de translation 410 des dispositifs de translations 400 sont entrainées dans le sens de rotation descendant. Les doigts 407 et écrous 406 des modules 110a et 110b étant bloquées en rotation par les barres de guidage 411, elles effectuent un mouvement de translation jusqu’à ce que les écrous 406 de chaque dispositif de translation 400 arrivent en contact avec la roue menée 413 de la croix de malte 412 de chaque dispositif de translation 400.
• Les doigts 407 des dispositifs 400 du module inférieur 110a sont orientés en position embrayée 454.
• Les vis 401 des systèmes de translation 410 des dispositifs de translations 400 du module inférieur 110a sont entrainés dans le sens de rotation ascendant ce qui
  • induit l’engagement des doigts 407 du module inférieur 110a dans des empreintes 301 du casier 300
  • puis initie le mouvement de translation verticale du casier 300, leur rotation étant bloquée par les barres de guidage 411. La rotation continue jusqu’à ce que les écrous 406 entrent en contact avec les paliers supérieurs 403 de modules inférieur 110a.
• Les doigts 407 du module supérieur 110b sont positionnées en position embrayée 454.
• Les vis 401 des systèmes de translation 410 des dispositifs de translations 400 du module supérieur 110b sont entrainées dans le sens de rotation ascendant ce qui induit l’engagement des doigts 407 du module supérieur 110b dans des empreintes 301 du casier 300 et l’escamotage des doigts 407 du module inférieur 110a des empreintes 301 du casier 300. Une fois désengagée les doigts 407 du module inférieur 110a sont de nouveau orientées en position débrayée 455.

According to a particular implementation, illustrated by Figures 10A, 10B, 10C, 10D, 10E and 10F , a translation movement of a rack 300 in a robotic system 100 controls at least eight translation devices 400 as described previously distributed on two modules 110, for example a lower module 110a and an upper module 110b. For example for an ascending movement, the steps of such a movement are as follows:

• The fingers 407 of the eight translation devices 400 of the lower 110a and upper 110b modules are oriented in a stable position at any height and the rack 300 rests on a horizontal actuator of the lower module 110a of the modular structure 200.
• The screws 401 of the translation mechanisms 410 of the translation devices 400 are driven in the downward direction of rotation. The fingers 407 and nuts 406 of the modules 110a and 110b being blocked in rotation by the guide bars 411, they carry out a translation movement until the nuts 406 of each translation device 400 come into contact with the driven wheel 413 of the Maltese cross 412 of each translation device 400.
• The fingers 407 of the devices 400 of the lower module 110a are oriented in the engaged position 454.
• The screws 401 of the translation systems 410 of the translation devices 400 of the lower module 110a are driven in the upward direction of rotation which
  • induces the engagement of the fingers 407 of the lower module 110a in the indentations 301 of the compartment 300
  • then initiates the vertical translation movement of the rack 300, their rotation being blocked by the guide bars 411. The rotation continues until the nuts 406 come into contact with the upper bearings 403 of lower modules 110a.
• The fingers 407 of the upper module 110b are positioned in the engaged position 454.
• The screws 401 of the translation systems 410 of the translation devices 400 of the upper module 110b are driven in the upward direction of rotation which induces the engagement of the fingers 407 of the upper module 110b in the recesses 301 of the locker 300 and the retraction of the fingers 407 of the lower module 110a of the imprints 301 of the locker 300. Once disengaged the fingers 407 of the lower module 110a are again oriented in the disengaged position 455.

The locker 300 therefore ends its vertical translation movement on the horizontal actuator of the upper module 110b.

The principle is similar for a downward 300 locker movement.

Claims (10)

Translation device (400) for a modular system for moving storage elements, said system comprising a plurality of adjacent modules (110) and at least one storage rack (300) capable of being moved from one module to another module adjacent, the device (400) comprising a translation mechanism (410) comprising a projecting drive finger (407) intended to cooperate with at least one complementary imprint (301) of the rack (300) to move said rack in translation,
characterized in that the translation mechanism (410) comprises a motorized endless screw (401) mounted in rotation between two bearings (402, 403), as well as a nut (406) cooperating with the screw (401) and carrying the driving finger (407), said device further comprising an indexing mechanism (420) adapted to transmit to the driving finger (407) indexing on at least two stable angular positions, one which is a disengaged position , the other which is a position in which the finger is able to cooperate with a complementary imprint of the locker to ensure the training of the latter. A translation device (400) according to claim 1, wherein the indexing mechanism comprises a Maltese cross mechanism (412). Translation device (400) according to claim 2, in which the Maltese cross mechanism comprises:
- a Maltese cross driven wheel (413) which is mounted, with the bearings (402, 403) which carry the endless screw (401), on an upright (111) of a module, said driven wheel (413) being coaxial with the endless screw (401), said endless screw (401) and said wheel (413) being capable of rotating relative to each other,
- a motorized crank (414) mounted on the upright and capable of moving the Maltese cross driven wheel between several positions
- at least one guide bar (411) which extends parallel to the endless screw, said guide bar being fixed relative to the Maltese cross driven wheel and in sliding connection relative to the nut. Translation device (400) according to one of claims 1 to 3, in which the indexing mechanism comprises at least two guide bars (411). Translation device (400) according to one of claims 3 or 4, characterized in that it comprises between the projecting finger (407) and a guide bar (411) at least one translation guide element. Translation device (400) according to one of the preceding claims, characterized in that an indexing mechanism (420) is adapted to transmit to the driving finger (407) indexing on at least three stable angular positions. Translation device (400) according to one of the preceding claims, characterized in that it comprises at least one brake which is adapted to block the endless screw (401) when said motor (404) is not actuated Modular system for moving storage elements comprising a plurality of adjacent modules (110) and at least one storage rack (300) capable of being moved in the modular structure from a module (110) to an adjacent module (110) , a module (110) comprising a chassis comprising uprights (111), at least one upright (111) carrying a translation device (400) according to one of the preceding claims. System according to claim 8 in which an upright (111) is an open profile. System according to claim 9 in which an upright (111) comprises support plates (201, 202) attached to the vicinity of its ends, the translation device (400) being fixed in a removable manner between these plates (201, 202).