AUTOMATED STORAGE SYSTEM

Abstract

The present invention provides a storage system (1) comprising a storage grid structure (104) and multiple container handling vehicles (200,300), the storage grid structure comprises vertical column profiles (102) defining multiple storage columns (105), in which storage containers (106) can be stored one on top of another in vertical stacks (107), and at least one transfer column (119,120), the column profiles are interconnected at their upper ends by top rails (110,111) forming a horizontal top rail grid (108) upon which the container handling vehicles (200,300) may move in two perpendicular directions, the container handling vehicles are able to retrieve storage containers (106) from, and store storage containers in, the storage columns (105), and transport the storage containers on the storage grid structure, wherein the storage grid structure (104) comprises at least one horizontal transfer section (2); and the storage system comprises multiple container transfer vehicles (6) and a transfer floor (5) on which the container transfer vehicles (6) may move horizontally, and the transfer section (2) is arranged at a level below the top rail grid (108) and extends from an external side (12) of the storage grid structure (104) to a position below the at least one transfer column (119,120) and comprises at least a section of the transfer floor (5); and each of the container transfer vehicles comprises a container carrier (38) for carrying a storage container (106) and a wheel arrangement (32a,32b) for moving the container transfer vehicle (6) in at least two perpendicular directions on the transfer floor (5); and wherein the at least one transfer column (119,120) extends from the top rail grid (108) to the transfer section (2), such that a storage container (106) may be transferred between the top rail grid (108) and the container carrier of one of the container transfer vehicles (6).

Claims

1. A storage system comprising a storage grid structure and multiple container handling vehicles, the storage grid structure comprises vertical column profiles defining multiple storage columns, in which storage containers can be stored one on top of another in vertical stacks, and at least one transfer column, the column profiles are interconnected at their upper ends by top rails forming a horizontal top rail grid upon which the container handling vehicles may move in two perpendicular directions, the container handling vehicles are able to retrieve storage containers from, and store storage containers in, the storage columns, and transport the storage containers on the storage grid structure, wherein the storage grid structure comprises at least one horizontal transfer section; and the storage system comprises multiple container transfer vehicles and a transfer floor on which the container transfer vehicles may move horizontally, and the transfer section is arranged at a level below the top rail grid and extends from an external side of the storage grid structure to a position below the at least one transfer column and comprises at least a section of the transfer floor; and each of the container transfer vehicles comprises a container carrier for carrying a storage container and a wheel arrangement for moving the container transfer vehicle in at least two perpendicular directions on the transfer floor; and wherein the at least one transfer column extends from the top rail grid to the transfer section, such that a storage container may be transferred between the top rail grid and the container carrier of one of the container transfer vehicles.

2. A storage system according to claim 1, comprising a guidance system for guiding the movement of the container transfer vehicles on the transfer floor.

3. A storage system according to claim 2, wherein the guidance system is arranged to guide the container transfer vehicles between a first position and a second position on the transfer floor, the first position directly below the at least one transfer column and the second position external to the storage grid structure.

4. A storage system according to claim 2, wherein the guidance system comprises at least one sensor on each of the container transfer vehicles for determining the position of each container transfer vehicle on the transfer floor and/or relative to the storage grid structure.

5. A storage system according to claim 4, wherein the at least one sensor comprises a sensor for detecting magnetism, receiving/transmitting radio signals, receiving/transmitting laser or receiving optic images.

6. A storage system according to claim 2, wherein the guidance system comprises guiding elements arranged to interact with the container transfer vehicles and/or the at least one sensor, the guiding elements arranged on or at any of the transfer floor and the storage grid structure.

7. A storage system according to claim 6, wherein at least some of the guiding elements are arranged at or below a lower end of the at least one transfer column, the guiding elements arranged to guide the container transfer vehicle to a first position directly below the at least one transfer column.

8. A storage system according to claim 6, wherein the guiding elements comprise reflectors for reflecting a laser from a laser sensor on the container transfer vehicles.

9. A storage system according to claim 6, wherein the guiding elements comprise a pair of guide barriers, wherein the pair of guide barriers comprises a first section arranged below the at least one transfer column, in which section the guide barriers are parallel and separated by a distance such that a container transfer vehicle, and/or a storage container arranged on the container carrier of the container transfer vehicle, may be accommodated between the guide barriers of the first section.

10. A storage system according to claim 9, wherein the pair of guide barriers comprises a second section extending from the first section, in which second section the guide barriers are separated by a gradually increasing distance.

11. A storage system according to claim 1, wherein each of the container transfer vehicles has a horizontal periphery allowing two container transfer vehicles to pass each other when below two adjacent transfer columns.

12. A storage system according to claim 1, wherein the wheel arrangement comprises at least two drive wheels being rotatable in opposite directions to allow the container transfer vehicle to turn around itself.

13. A storage system according to claim 1, wherein the at least one transfer column extends from the top rail grid to the transfer section, such that a container handling vehicle may transfer a storage container between the top rail grid and the container carrier of one of the container transfer vehicles.

14. A storage system according to claim 1, wherein the transfer section comprises multiple horizontal ceiling profiles supported by vertical support profiles, and the vertical column profiles of the at least one transfer column extend from the top rail grid to the ceiling profiles.

15. A storage system according to claim 14, wherein the lower ends of the vertical column profiles of the at least one transfer column are supported by the ceiling profiles.

16. A storage system according to claim 1, wherein the at least one transfer column provides a transfer port arranged at an upper level of the transfer section, the transfer port arranged to allow vertical transfer of a storage container between the transfer column and a container transfer vehicle, and the upper level arranged at a height sufficient to allow a container transfer vehicle to travel within the transfer section when carrying a storage container.

17. A method of retrieving a storage container from a storage system comprising a storage grid structure and multiple container handling vehicles (200,300), the storage grid structure comprises vertical column profiles defining multiple storage columns, in which storage containers can be stored one on top of another in vertical stacks, and at least one transfer column (119,120), the column profiles are interconnected at their upper ends by top rails (110,111) forming a horizontal top rail grid upon which the container handling vehicles (200,300) may move in two perpendicular directions, the container handling vehicles are able to retrieve storage containers from, and store storage containers in, the storage columns, and transport the storage containers on the storage grid structure, wherein the storage grid structure comprises at least one horizontal transfer section; and the storage system comprises multiple container transfer vehicles and a transfer floor upon which the container transfer vehicles may move horizontally, and the transfer section is arranged at a level below the top rail grid and extends from an external side of the storage grid structure to a position below the at least one transfer column and comprises at least a section of the transfer floor; and each of the container transfer vehicles comprises a container carrier for carrying a storage container and a wheel arrangement for moving the container transfer vehicle in at least two perpendicular directions on the transfer floor; and wherein the at least one transfer column extends from the top rail grid to the transfer section, such that a storage container may be transferred between the top rail grid and the container carrier of one of the container transfer vehicles; wherein the method comprises the steps of: retrieving a storage container from one of the storage columns by one of the container handling vehicles; moving the container handling vehicle and the storage container to the at least one transfer column; lowering the storage container to a container transfer vehicle arranged in the transfer section at a position below the transfer column; and moving the container transfer vehicle and the storage container to a position external to the storage grid structure.

18. A method according to claim 17, wherein the position external to the storage grid structure is selected from a position at a picking/stocking station or area, such that an operator or robot may access the content of the storage container while the storage container is arranged on the container transfer vehicle, a position below a transfer column in a transfer section of a second storage grid structure, and a position at a production facility, such as an assembly line or assembly station.

Description

SHORT DESCRIPTION OF THE DRAWINGS

[0142] The present invention is described in detail below by way of example only and with reference to the following drawings:

[0143] FIGS. 1 and 2 are perspective views of a prior art automated storage and retrieval system, wherein FIG. 1A and FIG. 2A show the complete system and FIG. 1B and FIG. 2B show examples of prior art container handling vehicles suitable for use in the system.

[0144] FIG. 3 is a perspective side view of a first exemplary storage system according to the invention.

[0145] FIG. 4 is a perspective view of the storage system in FIG. 3.

[0146] FIG. 5 is a perspective view of a second exemplary storage system according to the invention.

[0147] FIG. 6 is a perspective view of the storage system in FIG. 5.

[0148] FIG. 7 is a perspective view showing details of a transfer section of the storage system in FIGS. 5 and 6.

[0149] FIGS. 8-10 are detailed views of a third exemplary storage system according to the invention.

[0150] FIGS. 11 and 12 are perspective views of a container transfer vehicle for use in a storage system as shown in FIGS. 4-10.

[0151] FIG. 13 is a schematic drawing of an exemplary layout of a storage system according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0152] In the following, embodiments of the invention will be discussed in more detail with reference to the appended drawings. It should be understood, however, that the drawings are not intended to limit the invention to the subject-matter depicted in the drawings. Furthermore, even if some of the features are described in relation to the system only, it is apparent that they are valid for the related methods as well, and vice versa.

[0153] A first exemplary embodiment of a storage system according to the invention is shown in FIGS. 3 and 4. The storage system features a storage grid structure, multiple container handling vehicles 300 and container transfer vehicles 6. The major part of the storage grid structure is constructed in the same manner as in the prior art systems shown in FIGS. 1A and 2A. That is, the storage grid structure 104 comprises vertical column profiles 102 defining multiple storage columns 105, in which storage containers 106 can be stored one on top of another in vertical stacks 107. In FIGS. 3 and 4, the storage columns 105 and the stacks of storage containers are arranged behind grid screens 17. The column profiles 102 are interconnected at their top ends by top rails 110,111 forming a horizontal rail grid 108 (hereinafter termed the top rail grid) upon which container handling vehicles 300 may move in two perpendicular directions. To guide the vertical movement of the storage containers within a storage column, each of the vertical column profiles 102 has a cross-section featuring four corner sections 21, wherein each corner section is arranged to accommodate a corner of a storage bin 106.

[0154] In addition to the storage columns 105, the storage grid structure of the inventive storage system comprises multiple transfer columns 119,120 through which storage containers may be transferred between the top rail grid 108 (i.e. the top level of the grid), a first transfer section 2 and a second transfer section 2′. The transfer sections extend into the storage grid structure at a level below the top rail grid. The first transfer section 2 extends from an opening in an external side of the grid structure 104, while the second transfer section 2′ extends along or adjacent an external side section 12 of the storage grid 104. and below the multiple transfer columns 119,120. In an advantageous embodiment, especially in connection with large storage grids, the first transfer section 2 may extend to a substantially central position of the storage grid, and even pass all the way through the storage grid via a substantially central section of the storage grid structure 104. The first transfer section 2 will then provide transfer columns 119,120 at an internal section of the storage grid structure and also reduce the distance a storage handling vehicle 200,300 must travel to reach a transfer column.

[0155] Each transfer section 2,2′ is defined or constructed by multiple horizontal ceiling profiles 3, vertical support profiles 4 and a section of a transfer floor 5. The height H of the transfer section 2 may be defined by the distance between a lowermost surface of a ceiling profile 3 and the surface of the transfer floor 5. The multiple transfer columns 119,120 are defined by vertical column profiles extending from the top rail grid to the ceiling profiles 3. The lower ends of the vertical column profiles of the multiple transfer columns are supported by the ceiling profiles. Each transfer column provides a transfer port 20 arranged at the upper level of the transfer section. The height H of the transfer section 2 is sufficient to allow a container transfer vehicle 6 to travel within the transfer section 2 when carrying a storage container 106. The cross-section of the vertical column profiles 102 is arranged such that a transfer column 119,120 may guide a storage container 106 in a vertical direction and prevents the storage container from exiting the transfer column in a transverse direction. Thus, to transfer a storage container between a transfer column and a container transfer vehicle 6, the lower end of the transfer column must be arranged at a level at or above the height of the transfer section 2. In other words, the lower end of the transfer column must be arranged at a level sufficient to allow a container transfer vehicle 6 to be positioned below the transfer column when carrying a storage container.

[0156] An exemplary container transfer vehicle 6 is shown in FIGS. 11 and 12. The container transfer vehicle 6 features a vehicle body 16, a sensor which in this specific embodiment is a laser sensor 19, a wheel arrangement 32a, 32b allowing the vehicle to roll upon the transfer floor 5 and a container carrier 38 for accommodating a storage container 106 to be transferred. The disclosed container transfer vehicle 6 features two drive wheels 32a arranged on opposite sides of the vehicle body 16. The two drive wheels 32a may be rotated in opposite directions to allow the vehicle to turn around itself. Various container transfer vehicles suitable for the present inventive storage system are known and disclosed in for example WO 2018/189106 A1, WO 2018/163753 A1 and

https://industrial.omron.co.uk/en/products/mobile-robot#technology.

[0157] The differences in layout of the first transfer section 2 and the second transfer section 2′, the rectangular cross-section of the storage containers/transfer columns, as well as the specific wheel arrangement of the disclosed container transfer vehicles, entail that the horizontal direction of a storage container must be turned 90 degrees before it may be transferred through a transfer column of the first transfer section 2, i.e. turned 90 degrees relative the initial direction of the storage container when it enters the first transfer section 2. To turn/rotate the storage container as required, the container carrier 38 of each of the container transfer vehicles 6 are rotatably connected to the vehicle body 16, such that the container carrier may be automatically rotated relative to the vehicle body when required, see FIGS. 11 and 12. In further embodiments of the storage system, a storage container 106 may be rotated by turning the vehicle body 16. Alternatively, to avoid the issue of having to turn the storage containers, all transfer sections of the storage system may have a similar layout.

[0158] The storage system features a guidance system for guiding the movement of the container transfer vehicles 6 on the transfer floor 5 between a first position directly below one of the transfer columns 119,120 and a second position external to the grid structure 104. The guidance system comprises the laser sensor 19 arranged on the container transfer vehicles 6 for determining the position of the container transfer vehicle on the transfer floor 5 and/or relative to the grid structure 104. Other sensors suitable for this use are well known and include any sensor commonly used in guiding automated guided vehicles (AGV's). Such sensors include sensors for detecting magnetism, receiving/transmitting radio signals, detecting/transmitting laser, receiving optic images etc. The guidance system may also comprise any suitable guiding element arranged on/in the transfer floor and/or the grid structure for cooperation with the sensor(s) of the container transfer vehicle. Such guiding elements may for instance include laser reflectors arranged on the grid structure, magnetic wire or optic tapes arranged on/in the transfer floor, etc.

[0159] The storage system in FIGS. 3-4 has a guidance system featuring a laser sensor 19 (i.e. a sensor able to transmit and receive/detect a laser array, lidar or similar) arranged on the container transfer vehicles 6 and laser reflectors (not shown) arranged on the grid structure 104. In particular, the guidance system may comprise laser reflectors arranged at the lower end of the transfer columns 119,120, for instance at each of four column profiles 102 constituting a transfer column, to ensure that the container transfer vehicle 6 is able to be arranged at the exact position required to receive/deliver a storage container from/to the transfer column, i.e. at the first position.

[0160] The disclosed container carrier 38 is in the form of a tray upon which a storage container 106 may be accommodated. However, numerous alternative solutions for suitable container carriers 38 are envisaged and the main functional feature of all suitable containers carriers is the ability to receive a storage container 106 being lowered on top of the container carrier and retain the storage container during movement of the container transfer vehicle upon the transfer floor 5. The horizontal periphery of the container transfer vehicle 6 is preferably such that each of the multiple adjacent transfer columns 119,120 may be used to transfer a storage container 106 to a respective container transfer vehicle 6 simultaneously. To obtain the latter function, the horizontal periphery of the container transfer vehicle 6 fits within the horizontal area defined by one of the grid cells 122 of the top rail grid 108.

[0161] The grid columns arranged above the transfer section and not designated as transfer columns 119,120 may alternatively be used as storage columns 105′, see FIG. 13. This is achieved by adding stopper elements (e.g. brackets fastened to the relevant column profiles, not shown) at the lower end of the respective grid columns. The stopper elements are designed to support a storage container 106 being lowered into the respective grid column and prevent it from entering the transfer section 2 below. In this manner a minimum of potential storage space is lost from the storage grid structure 104 due to the transfer section 2. The stopper elements may also be used to provide an operator passage below a row of storage columns 105′ adjacent to the transfer section 2. In this manner, an operator or service person may access a container transfer vehicle 6, for instance in case of a failure preventing the vehicle from exiting the transfer section.

[0162] The transfer floor 5 extends out of the storage grid structure 104 and the container transfer vehicles 6 may be used to transfer storage containers 106 between multiple separate storage grid structures, transfer containers from a storage grid to a picking/stocking station, transfer storage containers to dedicated stocking zones, transfer storage containers to an assembly line for delivery of parts, etc.

[0163] A second exemplary embodiment of a storage system according to the invention is shown in FIGS. 5-7. In this embodiment, the differentiating feature in view of the embodiment discussed above is that the transfer sections 2,2′ feature guide barriers 7 (i.e. guiding elements) arranged on the transfer floor 5 to guide the transfer vehicles to a position directly below one of the transfer columns 119,120. The guide barriers 7 ensure that the container transfer vehicle is correctly positioned in a sideways direction, i.e. the direction perpendicular to the direction in which the vehicle moves towards the first position below the transfer column.

[0164] The guide barriers comprise a first section 9 of two parallel barriers arranged below one of the transfer columns. In the first section the barriers are separated by a distance substantially corresponding to the width of a container transfer vehicle. A second section 10 of guide barriers extends from the first section to facilitate the movement of the container handling vehicle to the first section of guide barriers. The second section features two guide barriers having a gradually increasing distance between them. In the embodiment of FIGS. 5-7, the guide barriers are beams or rails, but they may alternatively be constructed of any suitable element providing the required guiding function.

[0165] The first section of guide barriers may optionally feature stopping elements (not shown) arranged to stop the container transfer vehicle when in the correct position below a transfer column.

[0166] The final positioning of the container transfer vehicle below a transfer column must be very precise, i.e. within a margin of only a few millimetres. To obtain the required precision, the sensors on the container handling vehicles must either be very accurate, as the laser sensor 19 in the first exemplary embodiment in FIGS. 3 and 4, and/or the container handling vehicles may be physically guided by guide barriers 7. Container transfer vehicles having sensors with high accuracy, e.g. laser arrays, lidar etc. are commonly more expensive than corresponding vehicles having sensors of lower accuracy, e.g. sensors for detecting magnetic strips in the floor etc.

[0167] The preferred type of sensor on the container transfer vehicle and the preferred type of guiding element will depend on the layout of the specific storage system, the required transfer column capacity etc.

[0168] A third exemplary embodiment of a system according to the invention is shown in FIGS. 8-10. The main differentiating feature of the third embodiment in view of the storage system in FIGS. 5 to 7 is the construction/design of the guide barriers 7. In the third embodiment, the guide barriers are constructed from shaped plate elements 18 and connected at the lower end of the transfer columns. The guide barriers 7 feature a first 9 and second section 10 as discussed in connection with the second embodiment. A stopping element 8 is arranged at one end of the first section 9 distal from the second section 10. The stopping element will stop the container transfer vehicle 6 when it reaches the correct position below a transfer column 119,120.

[0169] The preferred arrangement and size of the transfer section 2 in any given storage system, as well as the positioning of the transfer columns 119,120, will depend on the size of the storage grid structure 104, the intended use of the storage system 1, the available space in which the storage system is arranged, the shape/layout of said space, etc. Independent of the specific positioning of the transfer section 2 within the storage grid structure, the storage system according to the invention will provide a number of advantages in view of the prior art storage systems, as disclosed throughout the present specification.

[0170] A schematic overview of an exemplary layout of an inventive storage system 1 is shown in FIG. 13. The exemplary layout illustrates some of the many advantages of the inventive storage system.

[0171] The storage system in FIG. 13 comprises a storage grid structure 104 featuring a transfer section 2 extending through the whole storage grid structure, i.e. the transfer sections extend from a first opening 11 in an external side 12 of the storage grid to a second opening 13 in an opposite external side 12′. In this manner, a container transfer vehicle 6 having received or delivered a storage container 106 via any of the multiple transfer columns 119,120 may exit the first 11 or the second opening 13 of the transfer section 2 depending on which pathway to a selected destination is most efficient.

[0172] The transfer floor 5 may in some embodiments interconnect the transfer columns 119,120 of the storage grid structure 104 with transfer columns 119,120 arranged in a separate (or second) storage grid structure, with a picking/stocking station 14, with a multi-use transfer floor area 15 and/or any other destination to which the transfer of a storage container is desired. The multi-use transfer floor area 15 may for instance be used for stocking large amounts of new items to the storage grid, as temporary parking for transfer vehicles carrying storage containers comprising high-demand items, and/or as a loading area for storage containers to enter the storage grids.

[0173] An area or section of the transfer floor 5 may also be used to accommodate container transfer vehicles 6 carrying storage containers 106 comprising high-demand items, i.e. a parking/storage section of the transfer floor. Such use may provide a highly efficient method of retrieving items that have a very high picking rate, i.e. that have a particularly high turnover. In prior art systems such high turnover items entail that the specific storage container(s) in which these items are stored is transferred back and forth between a storage column 105 and a picking/stocking station 14 more or less continuously. In the inventive storage system, items having a particularly high turnover may permanently (or at least intermediately) be stored in a storage container arranged on a transfer vehicle 6. In this manner, high turnover items may be accessed in a very short time, crowding at the transfer columns are further minimized and unnecessary use of the container handling vehicles 200,300 are avoided.

[0174] As is evident from the present disclosure, the inventive storage system provides a highly flexible container transfer and handling solution. Not only does the present solution facilitate the transfer of storage containers to or from the storage grid structure of an automated storage system, but it also provides for a simple and efficient solution for transfer of storage containers between separate storage grids, as well as between a storage grid and any location for further handling or processing of the storage containers and/or their content. The container handling capacity of the inventive storage system may easily be extended, and/or the function repurposed to accommodate any future changes in the requirements of a completed storage system. In addition, by having a transfer section and transfer floor as disclosed above, the container transfer and handling solution of the inventive storage system avoids any single point of failure which could disrupt the operation of the storage system.

REFERENCE NUMERALS

[0175] 1 Storage system

[0176] 2 Transfer section

[0177] 3 Horizontal ceiling profile

[0178] 4 Vertical support profile

[0179] 5 Transfer floor

[0180] 6 Container transfer vehicle

[0181] 7 Guide barrier

[0182] 8 Stopping element

[0183] 9 First section of guide barriers

[0184] 10 Second section of guide barriers

[0185] 11 First opening (in an external side of a storage grid)

[0186] 12 An external side of a storage grid

[0187] 13 Second opening (in an external side of a storage grid)

[0188] 14 Picking/stocking station

[0189] 15 Multi-use transfer floor area

[0190] 16 Vehicle body

[0191] 17 Grid screen

[0192] 18 Plate element

[0193] 19 Laser sensor

[0194] 20 Transfer port

[0195] 21 Corner section

[0196] 32a,32b Wheel arrangement

[0197] 38 Container carrier

[0198] 100 Framework structure

[0199] 102 Upright members of framework structure, i.e. vertical column profiles

[0200] 103 Horizontal members of framework structure

[0201] 104 Storage grid, storage grid structure

[0202] 105 Storage column

[0203] 105′ Storage column arranged above a transfer section

[0204] 106 Storage container

[0205] 107 Stack

[0206] 108 Top rail grid, rail system

[0207] 110 First set of parallel rails in first direction (X), top rails

[0208] 111 Second set of parallel rails in second direction (Y), top rails

[0209] 112 Grid column

[0210] 115 Grid opening

[0211] 119 Transfer column,

[0212] 120 Transfer column

[0213] 122 Grid cell

[0214] 200 Prior art container handling vehicle

[0215] 201,301 Wheel arrangement of prior art container handling vehicle

[0216] 300 Second container handling vehicle

[0217] X First direction

[0218] Y Second direction

[0219] Z Third direction