WAREHOUSE ROBOT AND METHOD FOR OPERATING A WAREHOUSE ROBOT

Abstract

A warehouse robot configured for automatically loading storage locations of a warehouse with containers, the warehouse robot including a plurality of electric motors; a horizontally oriented loading surface arranged at a topside of the warehouse robot and configured to receive a container of the containers; a plurality of motor rotatable wheels arranged at a bottom side of the warehouse robot and configured to move the warehouse robot on a ground, wherein rotation axes of the wheels are respectively oriented parallel to the loading surface, wherein first wheels of a first group of the wheels are synchronously oriented in a first driving direction, so that the warehouse robot is drivable in the first driving direction on the ground by motor driving the first wheels, wherein second wheels of a second group of the wheels are synchronously oriented in a second driving direction that differs from the first driving direction.

Claims

1. A warehouse robot configured for automatically loading storage locations of a warehouse with containers, the warehouse robot comprising: a plurality of electric motors; a horizontally oriented loading surface arranged at a topside of the warehouse robot and configured to receive a container of the containers; a plurality of motor rotatable wheels arranged at a bottom side of the warehouse robot and configured to move the warehouse robot on a ground, wherein rotation axes of the wheels are respectively oriented parallel to the loading surface, wherein first wheels of a first group of the wheels are synchronously oriented in a first driving direction, so that the warehouse robot is drivable in the first driving direction on the ground by motor driving the first wheels, wherein second wheels of a second group of the wheels are synchronously oriented in a second driving direction that differs from the first driving direction so that the warehouse robot is drivable in the second driving direction on the ground by motor driving the second wheels, wherein the first wheels of the first group and the second wheels of the second group are transferable into a passive condition and into an active condition, wherein a distance measured orthogonal to the loading surface between rotation axes of the first wheels of the first group in their passive condition and the loading surface and between rotation axes of the second wheels of the second group in their passive condition and the loading surface is less than a distance measured orthogonal to the loading surface between the rotation axes of the first wheels of the first group in their active condition and the loading surface and between the second wheels of the second group in their active condition and the loading surface, wherein the warehouse robot is transferable between a retracted unloading position and an extended loading position in an alternating manner, wherein an effective height of the warehouse robot measured orthogonal to the loading surface is greater in the loading position, than in the unloading position, wherein the first wheels of the first group and the second wheels of the second group are motor movable in a direction orthogonal to the loading surface between a retracted position and at least one extended position, wherein a distance between a rotation axis of a respective first wheel of the first group and the loading surface measured orthogonal to the loading surface is greater for the respective first wheel of the first group in the extended position than for the respective first wheel of the first group in the retracted position, and a distance between a rotation axis of a respective second wheel of the second group and the loading surface measured orthogonal to the loading surface is greater for the respective second wheel of the second group in the extended position than for the respective second wheel of the second group in the retracted position, wherein the wheels of at least one of the first group and the second group are motor movable into at least two extended positions where distances of the rotation axes of the first wheels of the first group from the loading surface measured orthogonal to the loading surface differ from distances of the rotation axes of the second wheels of the second group from the loading surface measured orthogonal to the loading surface, wherein the warehouse robot is transitionable from a first extended position into a second extended position between its loading position and its unloading position by moving the first wheels of the first group or the second wheels of the second group, and wherein the warehouse robot is operable so that all of the first wheels of the first group and all the second wheels of the second group are simultaneously provided in their active position, so that the distance between the rotation axes of all the first wheels and second wheels and the loading surface is identical for all the first wheels of the first group and all the second wheels of the second group.

2. The warehouse robot according to claim 1, wherein all the wheels of all the groups of the wheels are movable into at least two different extended positions or into exactly two extended positions.

3. The warehouse robot according to claim 1, wherein the rotation axes of all the wheels of all groups are arranged in a common retraction plane when all the wheels of all the groups are arranged in their retracted position.

4. The warehouse robot according to claim 1, wherein the rotation axes of all the wheels of all the groups are arranged in a common first extension plane when all the wheels of all the groups are arranged in their first extended position.

5. The warehouse robot according to claim 1, wherein the rotation axes of all the wheels of all the groups are arranged in a common second extension plane when all the wheels of all the groups are arranged in their second extended position.

6. The warehouse robot according to claim 1, wherein the first wheels of the first group or the second wheels of the second group are in their active condition and the warehouse robot is in its unloading position when the first wheels of the first group or the second wheels of the second group are in their first extended position.

7. The warehouse robot according to claim 1, wherein the first wheels of the first group or the second wheels of the second group are in their active condition and the warehouse robot is in its loading position when the first wheels of the first group or the second wheels of the second group are in their second extended position.

8. The warehouse robot according to claim 1, wherein at least one first wheel of the first group or at least one second wheel of the second group, or at least one first wheel of the first group and at least one second wheel of the second group, or all wheels respectively form part of an operating unit, and wherein a respective operating unit includes a lift motor configured to move the respective wheel between a retracted position and at least one extended position and a drive motor configured to drive the respective wheel to rotate about its rotation axis.

9. The warehouse robot according to claim 1, wherein the wheels of at least one group of the first group and the second group, or the first wheels of the first group and the second wheels of the second group are respectively supported at a respective pivot arm, and wherein the respective pivot arm is supported at a housing of the warehouse robot indirectly or directly pivotable about a pivot arm pivot axis.

10. The warehouse robot according to claim 9, wherein a component axis of the pivot arm of a respective wheel is oriented parallel to the loading surface when the pivot arm is in its retracted position, and/or oriented at an angle between 20 degrees and 70 degrees relative to the loading surface when the respective wheel is in its first extended position, and/or oriented at an angle between 80 degrees and 100 degrees relative to the loading surface when the respective wheel is in its second extended position.

11. The warehouse robot according to claim 8, wherein the wheels of at least one group of the first group and the second group, or the first wheels of the first group and the second wheels of the second group are respectively supported at a respective pivot arm, wherein the respective pivot arm is supported at a housing of the warehouse robot indirectly or directly pivotable about a pivot arm pivot axis, wherein a lift motor is indirectly or directly supported at the housing, wherein the lift motor is configured to pivot the pivot arm about the pivot arm pivot axis relative to the housing, wherein the drive motor is supported at the pivot arm so that the drive motor is movable on a circular path about the pivot am pivot axis when transitioning the respective wheel between its retracted position and at least one extended position.

12. A method for operating a warehouse robot including: a plurality of electric motors; a horizontally oriented loading surface arranged at a topside of the warehouse robot and configured to receive a container of the containers; a plurality of motor rotatable wheels arranged at a bottom side of the warehouse robot and configured to move the warehouse robot on a ground, a wherein rotation axes of the wheels are respectively oriented parallel to the loading surface, wherein first wheels of a first group of the wheels are synchronously oriented in a first driving direction, so that the warehouse robot is drivable in the first driving direction on the ground by motor driving the first wheels, wherein second wheels of a second group of the wheels are synchronously oriented in a second driving direction that differs from the first driving direction so that the warehouse robot is drivable in the second driving direction on the ground by motor driving the second wheels, wherein the first wheels of the first group and the second wheels of the second group are transferable into a passive condition and into an active condition, wherein a distance measured orthogonal to the loading surface between rotation axes of the first wheels of the first group in their passive condition and the loading surface and between rotation axes of the second wheels of the second group in their passive condition and the loading surface is less than a distance measured orthogonal to the loading surface between the rotation axes of the first wheels of the first group in their active condition and the loading surface and between the second wheels of the second group in their active condition and the loading surface, wherein the warehouse robot is transferable between a retracted unloading position and an extended loading position in an alternating manner, wherein an effective height of the warehouse robot measured orthogonal to the loading surface is greater in the loading position, than in the unloading position, the method comprising: a) driving the warehouse robot in the unloading position over a ground by motor driving the wheels of one of the groups and stopping the warehouse robot at a storage location loaded with a container so that the warehouse robot is stopped under the container; b) moving the wheels of at least one group into an extended position by motor after stopping the warehouse robot below the container, so that the warehouse robot is transitioned from its unloading position into its loading position and retrieves the container from the storage location so that the container is supported on the loading surface of the warehouse robot thereafter; c) driving the warehouse robot over the ground together with the container supported on the loading surface after receiving the container, wherein the driving is performed by motor driving the wheels of one of the groups; and d) moving the wheels of the group whose wheels where in the passive condition by a motor into an extended position in which the wheels of both groups are in contact with the ground simultaneously in order to change the driving direction, wherein the wheels of the other group whose wheels were in their active condition are moved towards their retracted position and thus into their passive condition.

13. The method according to claim 12, wherein the wheels of the group whose wheels were in the active condition are moved into their retracted position and thus into their passive condition in order to change the driving direction.

14. The method according to claim 13, wherein the change of the driving direction is performed when the warehouse robot is in its unloading position and when the warehouse robot is in its loading position.

15. The method according claim 12, wherein the wheels of both groups are simultaneously transitioned into a common extension position where all wheels are in contact with the ground simultaneously for transitioning the warehouse robot into its loading position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The invention will be subsequently described based on an embodiment with reference to drawing figures, wherein:

[0059] FIG. 1 illustrates a side view of a warehouse robot according to the invention in a loading position;

[0060] FIG. 2 illustrates an isometric view of the warehouse robot according to FIG. 1 in the loading position;

[0061] FIG. 3 illustrates a schematic side view of the warehouse robot according to FIG. 1 in the loading position;

[0062] FIG. 4 illustrates the side view according to FIG. 3 showing the warehouse robot in its unloading position;

[0063] FIG. 5 illustrates an isometric view of the warehouse robot according to FIG. 1 in its unloading position;

[0064] FIG. 6 illustrates the isometric view of the warehouse robot according to FIG. 5 in its loading position;

[0065] FIG. 7 illustrates a view of a bottom side of the warehouse robot according to FIG. 1;

[0066] FIG. 8 illustrates a detail of two operating units of the warehouse robot according to FIG. 1; and

[0067] FIG. 9 illustrates an operating unit of the warehouse robot according to FIG. 1.

DETAILED DESCRIPTION

[0068] An embodiment illustrated in FIGS. 1-9 includes a warehouse robot 1 configured to drive in a warehouse and to retrieve containers 3 from respective storage locations 2 of the warehouse and deposit the containers at the storage locations 2. The warehouse robot 1 includes a total of eight wheels 9, 10 in the illustrated embodiment, so that the warehouse robot 1 is drivable on the ground 11 by the wheels. In order to move the wheels 9, 10 the warehouse robot 1 includes a plurality of motors 4, 5 configured as electric motors in the illustrated embodiment. The wheels 9, 10 are respectively arranged at a bottom side 8 of the housing 26 of the warehouse robot 1. A loading surface 7 is configured at a topside 6 of the housing of the warehouse robot 1. The loading surface 7 is flat so that a container 3 supported on the loading surface 7 is oriented horizontally.

[0069] The wheels 9, 10 respectively include a rotation axis 12, and are drivable to rotate by at least some of the motors 4, 5. The wheels 9, 10 are arranged in the illustrated embodiment so that their rotation axis 12 are arranged in a common retraction plane 18 that is oriented parallel to the loading surface 7 when the wheels 9, 10 are respectively arranged in their retracted position.

[0070] In the illustrated embodiment the wheels 9, 10 are divided into two groups, wherein the wheels 9 of a first group are jointly oriented so that the warehouse robot 1 is drivable in a first driving direction 13 on the ground 11 when the wheels 9 are driven to rotate. On the other hand side the wheels 10 of the second group are jointly oriented so that the warehouse robot 1 is drivable on the ground 11 in a second driving direction 14 by a rotation drive of the wheels 10. In the illustrated embodiment the warehouse robot 1 has a rectangular shape overall wherein in particular the loading surface 7 is configured rectangular. The two groups of wheels 9, 10 are oriented in the illustrated embodiment so that the first driving direction 13 is oriented parallel to a first main axis of the warehouse robot 1 and the second driving direction 14 is oriented perpendicular to the first driving direction 13 and parallel to a second main axis of the warehouse robot 1. The two driving directions 13, 14 jointly define a plane that is parallel to the loading surface 7. The orientation of the first main axis of the warehouse robot 1 corresponds to a long side of the rectangular loading surface 7, whereas the second main axis of the warehouse robot 1 is oriented perpendicular to the first main axis and parallel to a narrow side of the rectangular loading surface 7. This is evident in particular from FIG. 2.

[0071] The wheels 9, 10 are alternatively provided in an active condition or in a passive condition during normal operation of the warehouse robot 1. Which wheels 9, 10 are provided in which condition is a function of a relative position of the wheels 9, 10 between each other. Therefore, the wheels 10 of a first group whose rotation axes 12 are at a distance 15 from the loading surface 7 measured perpendicular to the loading surface 7 are in their passive condition when the wheels 9 of the other group are at a distance 16 from the loading surface 7 also measured perpendicular to the loading surface 7 and the distance 16 of the wheels 9 is greater than the distance 15 of the wheels 10. Thus, the wheels 9 of the first group are therefore provided in their active condition. This means that the wheels 9 are in direct contact with the ground 11, so that the warehouse robot 1 is drivable on the ground 11 by driving the wheels 9 to rotate. The wheels 10 provided in the passive condition, however, have no contact with the ground 11. This is evident in particular from FIGS. 3-4.

[0072] It is furthermore evident from FIGS. 3-4 that the wheels 9, 10 can be provided in various positions relative to a housing 26 of the warehouse robot 1 in their active condition or passive condition. In the illustrated embodiment the wheels 9, 10 of both groups are respectively transitionable between their retracted position and two different extended positions. As stated supra the rotation axes 12 of all wheels are arranged in a common retraction plane 8 when they are respectively provided in their retracted position. By the same token, the first extension positions of the wheels 9, 10 are similar so that the rotation axes 12 of all wheels 9, 10 would be arranged in a common first extension plane 19 with all wheels 9, 10 in their first extension position. Furthermore, the rotation axes 12 of the wheels 9, 10 would be in a common second position plane with the wheels 9, 10 in their second extension position. When the wheels 10 of the first group are in their retracted position, the wheels 9 of the second group are always in their active condition when they assume one of the two extension positions. The retraction plane 8, the first extension plane 19 and the second extension plane 20 are oriented parallel to one another and parallel to the loading surface 7.

[0073] The two extension positions differ for all wheels 9, 10 in that the distance 16 of the rotation axis 12 of a respective wheel 9, 10 from the loading surface 7 is smaller when the wheels 9, 10 are in the first extension division, than when the wheels 9, 10 are in the second extension position. This is evident in particular when viewing FIGS. 3 and 4 together, wherein the wheels 9 of one group are in their second extension position in the situation illustrated in FIG. 3 and in their first extension position in the situation illustrated in FIG. 4. The wheels 10 of the other group are provided in their retracted position in both illustrated conditions.

[0074] Transitioning the wheels 9, 10 from their first extended position into their second extended position coincides with transitioning the warehouse robot 1 from its unloading position into its loading position in the illustrated embodiment. Thus, it is evident from FIGS. 3 and 4 that an effective height 17 of the warehouse robot 1 that is measured from a lowest spot of a respective wheel 9, 10 or from the ground 11 orthogonal to the loading surface 7 up to the loading surface 7 is the greater, the further the wheels 9, 10 are extended in their active position. Since the wheels 9, 10 arranged in their second extended position are extended further than in the first extended position the effective height 17 of the warehouse robot 1 increases when the wheels 9, 10 transition from the first extended position into the second extended position. The extended positions are thus selected so that a difference between the effective heights 17 as a function of the extended position of the wheels 9, 10 has the effect that a distance between the ground 11 and a bottom side of a container 3 stored at a storage location 2 of the warehouse is being traveled when the wheels 9, 10 transition from their first extended position into the second extended position. Put differently, the loading surface 7 is raised far enough so that the warehouse robot 1 initially impacts the bottom side of the container and lifts the container from its storage location when the wheels 9, 10 move further. Thereafter the container 3 is supported on the loading surface 7 so that the warehouse robot 1 is in its loading position. The difference between the two extended positions of the wheels 9, 10 of the one group is clearly evident from FIGS. 5 and 6.

[0075] Therefore the warehouse robot 1 is configured so that the motors 4 that transition the wheels 9, 10 from their retracted position into their two extended positions are also used for receiving a respective container 3 from its storage location. Thus, the motors 4 perform double duty, namely determining a driving direction of the warehouse robot 1 transitioning the wheels 9, 10 between their active condition and their passive condition and transitioning the warehouse robot 1 between its unloading position and its loading position.

[0076] It is particularly advantageous for lifting a container 3 when all wheels 9, 10 of the warehouse robot 1 are moved so that they are synchronously transitioned into their respective second extended position. The warehouse robot 1 is initially positioned below a container 3 for this purpose and thereafter the wheels 10 of the first group are brought in contact with the ground 11 synchronously with the wheels 9 of the other group. Since the warehouse robot 1 is still arranged in its unloading position the wheels 9, 10 of both groups are accordingly provided in their first extended position in which the rotation axes 12 of all wheels 9, 10 are arranged in a common extension plane 19. Lifting the container 3 is now performed by synchronously transitioning all wheels 9, 10 into their second extended position wherein the torques of all motors 4 that respectively cause the movement of one of the wheels 9, 10 work in combination. Accordingly the wheels 9, 10 are synchronously transitioned into their second extended position and cause the warehouse robot 1 to transition into its loading position. A total lifting force imparted by the warehouse robot 1 that lifts the container 3 from its storage location is therefore provided by all motors 4 in combination. After receiving the container 3 the wheels 9, 10 of a respective group that is not required immediately for the warehouse robot 1 to travel are moved back into their retracted position.

[0077] In order for a driving direction of the warehouse robot 1 to change the wheels 9, 10 of both groups can be jointly moved into the first extension position or the second extension position depending on the warehouse robot 1 being loaded with a container 3 or not. Thus, the wheels 9, 10 of a first group are initially provided in their active condition, whereas the wheels 9, 10 of the second group are provided in their passive condition. The wheels 9, 10 of the second group are then moved into the same extended position where the wheels of the first group that is still active are arranged already. Thereafter all wheels 9, 10 are in contact with the ground 11 and are therefore all provided in their active condition. Then the wheels 9, 10 of the first group are retracted, advantageously into their retracted position so that they are provided in their passive condition. Thereafter only the wheels 9, 10 of the second group are provided in their active condition. Thus, the change of the driving direction has been performed. Thus, it is particularly advantageous when the effective height 17 of the warehouse robot 1 does not change during the process, this means the loading surface 7 remains at the same elevation continuously.

[0078] Advantageously each of the wheels 9, 10 of the illustrated warehouse robot 1 forms part of an operating unit 21. The operating units 21 are evident from FIGS. 7-9. Each operating unit 21 respectively includes a wheel 9, 10, a lift motor 22 formed by a motor 4, a drive motor 23 formed by a motor 5, a transmission 28 associated with the drive motor 23, and a pivot arm 24. The lift motor 22 is mounted torque proof at the housing 26 of the warehouse robot 1 by bearings 27. The lift motor 22 transfers torque through the pivot arm 24 which is pivotable about a pivot axis 25 relative to the housing 26 by operating a lift motor 22. The drive motor 23 is arranged at an end of the pivot arm 24 together with the downstream transmission 28, wherein the end of the pivot arm 24 is oriented away from the housing 26, so that pivoting the pivot arm 24 about the pivot axis 25 moves the drive motor 23 and the transmission 28 on a circular path about the pivot axis 24. The respective wheel 9, 10 is also arranged at an end of the pivot arm 24 that is oriented away from the housing 26.

[0079] Moving the pivot arm 24 about the pivot axis 25 causes a proportional movement of the wheel 9, 10 arranged at the pivot arm in a direction perpendicular to the loading surface 7. This is evident from FIGS. 3 and 4 showing the pivot arm 24 pivotable about the pivot axis 25 relative to the housing 26. Therefore, the operating unit 21 is configured to move the respectively associated wheel 9, 10 in the direction perpendicular to the loading surface 7 using the lift motor 22 and the operating unit 21 is also configured to drive the wheel 9, 10 to rotate about its rotation axis 12 using the drive motor 23. The operating unit 21 is configured so that the pivot axis 25 of the pivot arm 24 is oriented parallel to the rotation axis 12 of the respective wheel 9, 10. This way the operating unit is configured particularly compact which saves installation space.

REFERENCE NUMERALS AND DESIGNATIONS

[0080] 1 warehouse robot [0081] 2 storage location [0082] 3 container [0083] 4 motor [0084] 5 motor [0085] 6 topside [0086] 7 loading surface [0087] 8 bottom side [0088] 9 wheel [0089] 10 wheel [0090] 11 ground [0091] 12 rotation axis [0092] 13 driving direction [0093] 14 driving direction [0094] 15 distance [0095] 16 distance [0096] 17 height [0097] 18 retraction plane [0098] 19 extension plane [0099] 20 extension plane [0100] 21 operating unit [0101] 22 lift motor [0102] 23 drive motor [0103] 24 pivot arm [0104] 25 pivot axis [0105] 26 housing [0106] 27 bearing [0107] 28 transmission