An order-picking vehicle equipped with a single motor to drive the drive wheels

Abstract

The invention relates to an electric vehicle intended for transporting loads, comprising at least three wheels for running along a floor, capable of rotating at least 90°, said wheels being mounted on swivel and drive devices attached to the chassis of the vehicle, each of which comprises a motor for actuating means for pivoting the wheels about a vertical axis intended to make it possible to pivot the wheels about themselves. According to the invention, such a vehicle comprises a single motor for driving in rotation said wheels, intended to operate means for driving in rotation said wheels housed in said slewing and driving device.

Description

[Technical field]

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

[0002] More specifically, the present invention relates to electric vehicles intended for transporting cargo.

[0003] The invention applies in particular to the automation of the flow of goods within a storage warehouse, for example an order picking warehouse of a logistics chain, or to the automation of a collection point order delivery service commonly known as a "drive". [Background technology]

[0004] Within the entire logistics chain, flow management within the warehouse and handling of products plays a key role.

[0005] Traditionally, order pickers travel around the warehouse and collect each item in an order from its location on a shelf in a steel rack.

[0006] It should be noted that such a mechanism means that collectors travel long distances throughout the working day, causing fatigue and lost time if the routes are not optimized.

[0007] Another drawback is that the collector must know the layout of the warehouse perfectly so as not to waste time.

[0008] In order to limit travel fatigue, improve picking management, and reduce the time and costs required to pick orders, warehouse mechanisms have been invented in which products are collected from steel racks by robots and then transported to order picking stations by these same robots.

[0009] In particular, it is proposed to implement an automated guided vehicle that can travel along the floor and rise along the steel racks to go and collect the products stored in containers.

[0010] Thus, for example, from DE 10 200 03 133 A1 an automated guided vehicle is known which is equipped on the sides of its chassis with retractable gears which can be deployed laterally. These gears are intended to engage in vertical racks attached to two steel racks in order to allow the vehicle to rise between them in order to reach the level of the containers to be collected.

[0011] To guide these vehicles along the floor, especially between the steel racks, it has been considered to install circulating rails in the floor, but the installation of rails is expensive and their presence makes the floor more difficult to clean.

[0012] It is also being considered to have automated guided vehicles run in a straight line along the floor between the steel racks, and sometimes even underneath them.

[0013] In order to be able to control the changes of direction of the vehicles without losing time going around bends, it has been proposed to mount each of the driving wheels of these vehicles on an independent motorized slewing turret. Each of these known turrets comprises a motor for slewing the wheel about a vertical axis and a motor for driving the wheel in rotation in order to control the movement of the wheel at each moment.

[0014] One drawback of these known techniques is that they are complex and expensive to implement, particularly due to the fact that two motors are required per turret. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] International Publication No. 2010 / 100513 Brochure Summary of the Invention [Problem to be solved by the invention]

[0016] SUMMARY OF THE PRESENT EMBODIMENT It is therefore an object of the present invention to alleviate, inter alia, the above-mentioned disadvantages of the prior art.

[0017] More specifically, it is an object of the present invention to provide an electric vehicle technique that is easy to implement.

[0018] Another object of the present invention is to provide an inexpensive electric vehicle technology.

[0019] Another object of the present invention is to provide a viable electric vehicle technique. [Means for solving the problem]

[0020] These objects, as well as others that will become apparent hereinafter, are achieved by means of an electric vehicle intended to transport loads, comprising at least three drive wheels intended to run along a floor and capable of pivoting at least 90°, said drive wheels being mounted on swivel and drive devices attached to the chassis of the vehicle, each of which comprises a motor for actuating means for pivoting the drive wheels about a vertical axis intended to make it possible to pivot the drive wheels about themselves.

[0021] According to the invention, such a vehicle comprises a single motor for driving in rotation said drive wheels, intended to operate means for driving in rotation said drive wheels housed in said slewing and driving device.

[0022] Therefore, in a novel manner, the invention proposes to implement a vehicle with a single motor for driving all driving wheels of the vehicle, which makes it possible to simplify the implementation of the vehicle and make it lighter.

[0023] This ingeniously allows the vehicle to change direction and start at right angles, thus traveling along a path ordered according to the grid plan. Indeed, the inventors have noted that if the vehicle is only supposed to move vertically, the implementation of a single drive motor driving the wheels at substantially the same speed is sufficient to correct small deviations in the angular position of the wheels relative to these directions of movement. Thus, no drift of the vehicle occurs.

[0024] In a particular embodiment of the invention, the vehicle is an automated guided vehicle.

[0025] According to a particular embodiment of the invention, the means for pivoting the drive wheel comprises a first gear driven in rotation by one of the motors for actuating a pivoting means engaging a second gear of a vertical shaft, the second gear being attached to a fork straddling the drive wheel, the axle of the drive wheel being mounted to pivot relative to the blades of the fork extending on either side of the drive wheel.

[0026] Preferably, the drive means comprises a first conical pinion and a second conical pinion arranged relative to each other to form an angular transmission, the axle of the first pinion being coaxial with the axle of the second gear and the axle of the second pinion being coaxial with the axle of one of the drive wheels.

[0027] In an advantageous embodiment of the invention, said drive motor actuates said means for driving in rotation said drive wheels of each of said slewing and drive devices by means of a belt.

[0028] Preferably, said pivoting and drive devices are substantially identical.

[0029] According to a particular embodiment of the invention, an electric vehicle as described above has four drive wheels mounted on swivel and drive units attached substantially to the four corners of the chassis.

[0030] In certain embodiments of the invention, at least one of the swivel and drive devices is configured such that the axle of the second pinion of that device passes through the centre of a drive wheel attached to that device.

[0031] At this time, the drive wheels do not rotate during their turn about the vertical axis.

[0032] Other characteristics and advantages of the invention will appear more clearly on reading the following description of one embodiment of the invention, given purely as an illustrative and non-limiting example, and on reading the accompanying drawings, in which: [Brief description of the drawings]

[0033] [Figure 1] FIG. 1 is a schematic perspective view of an order picking warehouse equipped with an example of an embodiment of an automated guided vehicle according to the present invention. [Diagram 2] FIG. 2 is a detailed view of one of the vehicles presented with reference to FIG. 1. [Diagram 3] FIG. 3 is a detailed top view of the system for driving the drive wheels of the vehicle presented with reference to FIG. 2; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] 1 shows a warehouse 10 intended to store products with a view to shipping them. The warehouse is divided into a storage area 11 and an order picking area in which is located an order picking station 12 in which an operator 13 prepares packages with the products of an order.

[0035] The storage area 11 is organized into steel racks 14 with multiple levels of shelves supported by posts 15 on which are placed containers 16 containing the stored products or items.

[0036] A fleet of automated guided vehicles 17 ensures the transport of containers 16 between the storage area 11 and the order picking station 12 .

[0037] When the robot 17 receives location information about a container 16 containing one or more items that it is to collect to complete an order processed by an operator 13, the robot 17 runs along the floor to the bottom of the steel rack 14 in which the container 16 is stored and positions itself in the aisle 18 between this steel rack 14 and the steel rack facing it.

[0038] During this movement, the robot 17 follows the direction of the lines marked on the floor, which are arranged according to the diagram of the grid 19. Thus, as can be seen in FIG. 1, the robot 17 follows the direction of the vertical lines 19 1 or line 19 1 19 horizontal lines perpendicular to 2 1 and 2, and can circulate under the steel rack 14.

[0039] This robot 17 is then transformed into the robot 17 shown in FIG. 1 As shown in Fig. 1, the operator 13 climbs up to the shelf where the container 16 is stored by leaning against two steel racks and takes the container from the steel rack. It then descends between the two steel racks and, once it reaches the floor, transports the container 16 to the order picking station 12 by traveling along a grid 19. The operator 13 simply receives the ordered quantity of goods and packages them.

[0040] 2 shows a robot 17 carrying a container 16 in an aisle 18 at the bottom of two steel racks 21 and 22. In this particular embodiment of the invention, the width of the robot's chassis 23 and the width of the container 16 are advantageously smaller than the space between two adjacent posts 15 of the steel rack 21 or the steel rack 22, in order to allow the robot to pass between these posts.

[0041] The robot 17 is equipped at the four corners of its chassis 23 with electrically retractable gears 25 which can be retracted inside the chassis 23 or deployed outside the chassis 23 .

[0042] To climb between the two steel racks 22 and 23, the robot 17 deploys a motorized arm 26 carrying a gear 25 on the outside of the chassis 23 in diagonal extension of the chassis until the gear reaches a rack 27 attached to the post 15 and can engage with the post 15, as can be seen in FIG. 2.

[0043] Additionally, the robot 17 has four drive wheels 29 mounted on turrets at the four corners of the chassis 23 and driven by a single motor 210 .

[0044] 3, which is a partial top view of the system for driving the drive wheels 29, the motor 210 drives a toothed belt 31 via a roller 32 coupled to the drive shaft. The belt 31 is held taut using three tensioner rollers 34.

[0045] The movement of the belt 31 drives a rotating pulley 33 which is connected to the drive wheel 29 by means of two pinions forming an angular transmission.

[0046] Rotation of pulley 33 rotates a first pinion attached to and coaxial with the pulley, which engages a second vertically oriented pinion attached to one end of the wheel axle, which second pinion drives the drive wheel 29 in rotation at a rotational speed proportional to the reduction ratio of the gearing formed by the two pinions.

[0047] In this particular embodiment of the invention, the four turrets are identical and the motor 210 rotationally drives the four drive wheels 29 at the same speed. Note that this single motor allows the vehicle to rotate about itself and thus allows the vehicle to be oriented perpendicular to its forward direction to enable the vehicle to make right angle turns.

[0048] It should be noted, moreover, that each of the turrets has a system for pivoting the forks, on which the drive wheels are mounted, making it possible to turn the drive wheels independently in different directions. This pivoting system comprises a stepper motor 35 and a gear 36 on an axis coaxial with the axis of the pulley 33, actuated by the motor 35 by means of an intermediate pinion attached to the shaft of the motor 35. [Explanation of symbols]

[0049] 10 Warehouse, 11 Storage area, 12 Order picking station, 13 Operator, 14 Steel rack, 15 Post, 16 Container, 17 Automated guided vehicle / robot, 17 1 Robot, 18 Passage, 19 Grid, 19 1 Vertical lines, 19 2 Horizontal line, 21 steel rack, 22 steel rack, 23 chassis, 25 gear, 26 motorized arm, 27 rack, 29 drive wheel, 31 toothed belt, 32 roller, 33 rotating pulley, 34 tensioner roller, 35 stepper motor, 36 gear, 210 motor

Claims

1. An electric vehicle (17) for the purpose of transporting goods, Comprising at least three drive wheels (29) intended to run along the floor and capable of turning at least 90°, The drive wheels (29) are attached to a turning and driving device attached to the chassis (23) of the vehicle, Each of the turning and driving devices comprises a motor for actuating means for turning the drive wheels (29) about a vertical axis, intended to enable the drive wheels (29) to turn about themselves, The electric vehicle is characterized by comprising a single motor (210) for rotationally driving the drive wheels (29), intended to actuate the means for rotationally driving the drive wheels accommodated in the turning and driving device. An electric vehicle (17).

2. The vehicle according to claim 1, characterized in that the vehicle (17) is an automated guided vehicle.

3. The means for turning the drive wheels (29) comprises a first gear rotatably driven by one of the motors for actuating the turning means engaging with a second gear of the vertical axis, the second gear being attached to a fork straddling the drive wheels, and the axle of the drive wheels being attached to pivot with respect to the blades of the fork extending on both sides of the drive wheels (29). The vehicle according to claim 1 or 2.

4. The drive means comprises a first conical pinion and a second conical pinion arranged relative to each other to form an angle transmission part, the axle of the first pinion being coaxial with the axle of the second gear, and the axle of the second pinion being coaxial with the axle of one of the drive wheels (29). The vehicle according to claim 3.

5. The vehicle according to claim 1 or 2, characterized in that the drive motor (210) actuates the means for rotationally driving the drive wheels of each of the turning and driving devices by means of a belt (31).

6. The vehicle according to claim 3, characterized in that the drive motor (210) actuates the means for rotationally driving the drive wheels of each of the turning and driving devices by means of a belt (31).

7. The vehicle according to claim 1 or 2, characterized in that the turning and driving devices are substantially identical.

8. The vehicle according to claim 1 or 2, characterized in that it has four drive wheels (29) attached to the turning and driving devices attached to substantially four corners of the chassis.

9. The vehicle according to claim 3, characterized in that at least one of the turning and driving devices is configured such that the axle of the second pinion of this device passes through the center of the drive wheel (29) attached to this device.

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