Order preparation vehicle, with a single drive motor for the driven wheels

Description

1. Field of the invention

[0001] The field of the invention is that of warehouse logistics and in particular the transport of parts or products.

[0002] More specifically, the invention relates to a motorized trolley intended to transport a load.

[0003] The invention finds particular application in the automation of the flow of goods in a storage warehouse, for example in an order preparation warehouse in a logistics chain, or in the automation of an order delivery service to a collection point, commonly called a "drive". 2. State of the art

[0004] In the global supply chain, the management of flows and handling of products within a warehouse play a decisive role.

[0005] Traditionally, an order picker moves around the warehouse to collect each product in an order from its location on a shelf in a rack.

[0006] It is noted that such an organization implies that the preparer travels long distances during a working day, which causes fatigue and loss of time when the journey is not optimized.

[0007] Another disadvantage is that the picker must be fully familiar with the layout of the warehouse in order not to waste time.

[0008] To limit fatigue caused by travel, improve picking management, and reduce order preparation time and costs, we have devised a warehouse organization where products are picked from shelves or by robots and then transported by these same robots to order preparation stations.

[0009] In particular, it has been proposed to implement self-guided trolleys which are capable of both moving on the ground and climbing along shelves to pick up products stored in bins.

[0010] For example, document WO 2010 / 100513 A2 discloses a self-guided trolley equipped on the sides of its chassis with retractable toothed wheels that can be deployed laterally. These toothed wheels are intended to mesh with vertical racks fixed to shelves, to enable the trolley to rise between two shelves in order to reach the level of a bin to be collected.

[0011] In order to guide these trolleys on the floor, particularly between the shelves, consideration was given to installing circulation rails on the floor. However, installing rails is expensive, and the presence of rails makes cleaning the floor more difficult. Consideration was also given to rolling self-guided trolleys directly on the floor between the shelves and sometimes even under the shelves.

[0012] In order to be able to control the changes of direction of the trolley without wasting time describing turns, it has been proposed to mount each of the driving wheels of these trolleys on an independent motorized pivoting turret. These known turrets are each equipped with a motor to pivot the wheel around a vertical axis and a motor to drive the wheel in rotation, to control the movement of the wheels at all times.

[0013] A disadvantage of these known techniques is that they are complex and expensive to implement, particularly since two motors are required per turret.

[0014] Other motorized trolleys are known from documents JP 2014 103878 A and JP S62 103223 A. 3. Objectives of the invention

[0015] The invention therefore aims in particular to overcome the drawbacks of the state of the art cited above.

[0016] More specifically, the invention aims to provide a motorized trolley technique which is simple to implement.

[0017] Another object of the invention is to provide a motorized trolley technique which is inexpensive.

[0018] An objective of the invention is also to provide a motorized trolley technique which is reliable. 4. Statement of the invention

[0019] These objectives, as well as others which will appear subsequently, are achieved using a motorized trolley intended to transport a load comprising at least 3 driving wheels intended to roll on the ground, capable of pivoting at least 90°, said driving wheels being mounted on pivoting and driving devices fixed to the chassis of said trolley, each of said pivoting and driving devices comprising a motor for actuating means for pivoting a driving wheel around a vertical axis, intended to allow a driving wheel to pivot around itself.

[0020] According to the invention, such a trolley comprises a single motor for driving said drive wheels in rotation and intended to actuate means for driving said drive wheels in rotation housed in said pivoting and driving devices.

[0021] Thus, in a novel manner, the invention proposes to implement a trolley equipped with a single drive motor for all of the trolley's drive wheels, which makes it possible to simplify the implementation of the trolley and to lighten it. This cleverly allows the trolley to change direction and set off again at right angles and thus to travel on an ordered path following the plan of a grid. The inventors have in fact noted that when the trolley is designed to move only in perpendicular directions, the implementation of a single drive motor, which drives the wheels at substantially the same speed, is sufficient to correct small deviations in the angular positions of the wheels relative to these directions of movement. There is thus no drift of the trolley.

[0022] In a particular embodiment of the invention, said trolley is an automatic guided trolley.

[0023] According to a particular embodiment of the invention, said means for pivoting a drive wheel comprise a first toothed wheel driven in rotation by one of said motors for actuating the pivoting means meshed with a second toothed wheel with a vertical axis, said second toothed wheel being fixed on a fork overlapping said drive wheel, the axis of said drive wheel being pivotally mounted relative to the sleeves of said fork extending on either side of said drive wheel.

[0024] Preferably, said drive means comprise a first pinion and a second bevel pinion arranged relative to each other so as to form an angle transmission, the axis of said first pinion being coaxial with that of said second toothed wheel and the axis of the second pinion being coaxial with the axis of one of said drive wheels.

[0025] In an advantageous embodiment of the invention, said drive motor actuates said means for driving in rotation said drive wheels of each of said pivoting and driving devices by means of a belt.

[0026] Preferably, said pivoting and driving devices are substantially identical.

[0027] According to a particular embodiment of the invention, a motorized trolley as described above has four drives mounted on pivoting and driving devices fixed substantially to the four corners of said chassis. In a particular embodiment of the invention, at least one of said pivoting and driving devices is configured so that the axis of the second pinion of this device passes through the center of the driving wheel mounted on this device.

[0028] The drive wheel then does not rotate when pivoting around a vertical axis. 5. List of figures

[0029] Other characteristics and advantages of the invention will appear more clearly on reading the following description of an embodiment of the invention, given as a simple illustrative and non-limiting example, and the appended drawings among which: there figure 1 is a schematic perspective view of an order preparation warehouse equipped with an exemplary embodiment of automatic guided trolleys according to the invention; figure 2 is a detailed representation of one of the carts presented with reference to the figure 1 ; there figure 3 is a detailed view, from above, of the drive system of the driving wheels of the trolley presented with reference to the figure 2 . 6. Detailed description of the invention

[0030] It has been illustrated on the figure 1a warehouse 10 intended for the storage of products for shipment. This warehouse is divided between a storage area 11 and an order preparation area in which order preparation stations 12 are arranged at which operators 13 prepare packages with the products of an order.

[0031] The storage area 11 is organized into shelves 14 comprising shelves on several levels supported by uprights 15, on which bins 16 are stored which contain the stored products or articles.

[0032] A fleet of automatic guided vehicles 17 ensures the transport of the bins 16 between the storage area 11 and the order preparation stations 12.

[0033] When a robot 17 receives location information for a bin 16 containing one or more items to be picked up to complete an order processed by an operator 13, the robot 17 rolls on the ground to the foot of the shelf 14 where the bin 16 is stored and positions itself in the aisle 18 between this shelf 14 and the shelf facing it.

[0034] During this movement, the robot 17 follows the direction of strips drawn on the ground organized according to the pattern of a grid 19. As can be seen in the figure 1 , a robot 17 can thus move in the direction of the longitudinal strips 19 1 or the lateral strips 19 2 perpendicular to the strips 19 1 and can circulate under the shelves 14.

[0035] This robot 17 then climbs, in the manner of the robot 17 1 shown on the figure 1, by leaning on two shelves up to the level of the shelf where the bin 16 is stored and extracts it from the shelf. It then goes back down between the two shelves, and once on the ground, transports the bin 16 to the order preparation station 12 by moving along the grid 19. The operator 13 only has to pick the quantity of items ordered and pack them.

[0036] It has been represented on the figure 2 a robot 17 carrying a bin 16 in an aisle 18 at the foot of two shelves 21 and 22. In this particular embodiment of the invention, the width of the chassis 23 of the robot and that of the bin 16 are advantageously less than the spacing between two adjacent uprights 15 of the shelf 21 or of the shelf 22 in order to allow the robot to pass between these uprights.

[0037] The robot 17 is equipped at the four corners of its chassis 23 with motorized retractable toothed wheels 25 which can be retracted inside the chassis 23 or deployed outside the chassis 23.

[0038] To climb between the two shelves 22 and 23, the robot 17 deploys the motorized arms 26 carrying the toothed wheels 25 outside the chassis 23 in the extension of the diagonals of the chassis until the toothed wheels reach racks 27 fixed on the uprights 15, as can be seen in the figure 2 , and can mesh with them.

[0039] The robot 17 also has four drive wheels 29 mounted on turrets at the four corners of the chassis 23 and driven by a single motor 210. As can be seen in the figure 3, which is a partial top view of the drive system of the driving wheels 29, the motor 210 drives a toothed belt 31, via a roller 32 coupled to the drive shaft. This belt 31 is kept tensioned using three tensioner rollers 34.

[0040] The running of the belt 31 drives in rotation pulleys 33 connected to the driving wheels 29 by means of two pinions forming an angle transmission. The rotation of a pulley 33 causes a first pinion fixed and coaxial with this pulley to rotate, which meshes with a second pinion oriented perpendicularly, fixed to one end of the axis of the wheel, which drives the driving wheel 29 in rotation with a rotation speed proportional to the reduction ratio of the gear formed by the two pinions.

[0041] In this particular embodiment of the invention, the four turrets are identical and the motor 210 drives the four drive wheels 29 to rotate at the same speed. It should be noted that this single motor allows the carriage to rotate on itself and thus to orient the carriage perpendicular to its previous direction to allow it to make a right angle.

[0042] It should also be noted that each of the turrets has a fork pivoting system on which a drive wheel is mounted, making it possible to orient the drive wheels in different directions, independently. This pivoting system comprises a stepper motor 35 and a toothed wheel 36 with an axis coaxial with that of the pulley 33, actuated by the motor 35 via an intermediate pinion mounted on the shaft of the motor 35.

Claims

1. Motorised vehicle (17) intended to transport a load comprising at least three drive wheels (29) intended to run along the floor, capable of pivoting at least 90°, said drive wheels (29) being mounted on pivoting and driving devices attached to the chassis (23) of the vehicle, each of the pivoting and driving devices comprising a motor for actuating means for pivoting a drive wheel (29) about a vertical axis, intended to make it possible to pivot a drive wheel (29) about itself, said motorised vehicle comprising a single motor (210) for driving in rotation said drive wheels (29) intended to actuate the means for driving in rotation said drive wheels housed in said pivoting and driving devices.

2. Vehicle according to claim 1, characterised in that said vehicle (17) is an automatic guided vehicle.

3. Vehicle according to any one of claims 1 and 2, characterised in that said means for pivoting a drive wheel (29) comprise a first toothed wheel driven in rotation by one of said motors for actuating the pivoting means engaged with a second toothed wheel of vertical axis, said second toothed wheel being attached to a fork straddling said wheel, the axle of said drive wheel being mounted pivoting in relation to the blade of said fork extending on either side of said drive wheel (29).

4. Vehicle according to claim 3, characterised in that said driving means comprise a first conical pinion and a second conical pinion arranged relative to one another so as to form an angular transmission, the axle of said first pinion being coaxial with that of said second toothed wheel and the axle of the second pinion being coaxial with the axle of one of said drive wheels (29).

5. Vehicle according to any one of claims 1 to 4, characterised in that said drive motor (210) actuates said means for driving in rotation said drive wheels of each of said pivoting and driving devices by means of a belt (31).

6. Vehicle according to any one of claims 1 to 5, characterised in that said pivoting and driving devices are substantially identical.

7. Vehicle according to any one of claims 1 to 6, characterised in that it has four drive wheels (29) mounted on pivoting and driving devices attached substantially to the four corners of said chassis.

8. Vehicle according to claim 3, characterised in that at least one of said pivoting and driving devices is configured so that the axle of the second pinion of this device passes through the centre of the drive wheel (29) mounted on this device.