Unloading apparatus and unloading method

Patent metadata

Field	Value
Publication number	US-10730708-B2
Application number	US-201816110689-A
Country	US
Kind code	B2
Filing date	Aug 23, 2018
Priority date	Sep 7, 2017
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

An unloading apparatus for unloading cargo items from a cargo group on a cargo bed includes a cargo bed lifting and lowering mechanism, a first detection unit that measures heights of cargos items and detects positions of cargo items forming the upper surface of the cargo group, a moving device that moves the cargo items to an unloading position, a second detection unit that detects whether a lower end of a cargo item being held by the moving device is above a position that is higher than the highest position of the cargo items at the upper surface of the cargo group, and a controller. The controller controls the raising and lowering of cargo bed in conjunction with the lifting of cargo items. The controller also controls the moving of the cargo items to the unloading position.

First claim

What is claimed is:

1. An unloading apparatus that unloads cargo items from a cargo group on a cargo bed, the unloading apparatus comprising:
a cargo bed lifting and lowering mechanism that lifts and lowers a cargo bed;
a first detection unit that measures heights of cargo items forming an upper surface of a cargo group and positions, in plan view, of the cargo items forming the upper surface of the cargo group;
a moving device that moves the cargo items to an unloading position by individually holding and lifting a cargo item based on a measurement by the first detection unit;
a second detection unit that detects whether a lower end of a cargo item being held by the moving device is above a position that is higher than the highest position of the cargo items at the upper surface of the cargo group; and
a controller configured to:
control the cargo bed lifting and lowering mechanism to lower the cargo bed in conjunction with the lifting of cargo items by the moving device, and stop the lowering of the cargo bed based on a detection result of the second detection unit, and
control the moving device to move the cargo items to the unloading position.

2. The unloading apparatus according to claim 1 , wherein the controller controls the cargo bed lifting and lowering mechanism to lift the cargo bed to keep the upper surface of the cargo group at a set position as cargo items are removed from the cargo group.

3. The unloading apparatus according to claim 2 , wherein the second detection unit measures a distance to the cargo items in a horizontal direction and detects whether the lower end of a cargo item being held by the moving device is above the highest position of any remaining cargo item in the cargo group next by a predetermined distance.

4. The unloading apparatus according to claim 2 , wherein the controller is configured to control the second detection unit to lift and lower in conjunction with the lifting and lowering of the cargo bed.

5. The unloading apparatus according to claim 1 , wherein the second detection unit measures a distance to the cargo items in a horizontal direction and detects whether the lower end of a cargo item being held by the moving device is above the highest position of any remaining cargo item in the cargo group next by a predetermined distance.

6. The unloading apparatus according to claim 1 , wherein the second detection unit is a laser range finder.

7. The unloading apparatus according to claim 1 , wherein the second detection unit is configured to lift and lower in conjunction with the lifting and lowering of the cargo bed.

8. The unloading apparatus according to claim 1 , further comprising:
a cargo bed rotating mechanism that rotates the cargo bed, wherein
the controller controls rotation of the cargo bed in a direction in which the next cargo to be held by the moving device becomes close to the unloading position.

9. The unloading apparatus according to claim 8 , wherein the controller is configured to control the second detection unit to lift and lower in conjunction with the lifting and lowering of the cargo bed.

10. The unloading apparatus according to claim 8 , wherein the controller controls the cargo bed lifting and lowering mechanism to lift the cargo bed after cargo items have been removed for the cargo group to keep the upper surface of the cargo group at a set position.

11. A method of unloading cargo items from a cargo group on a cargo bed to an unloading position, the method comprising:
measuring heights of the cargo items at an upper surface of the cargo group;
detecting positions of the cargo items in the cargo group in a plan view;
holding and then lifting an individual cargo item with a moving device using detected positions and measured heights of the cargo items;
lowering the cargo bed during the lifting of the individual cargo item;
stopping the lowering of the cargo bed once a detected height of a lower end of the individual cargo item being lifted by the moving device is above a measured height of an adjacent cargo item which was adjacent to the individual cargo item within the cargo group, the position being above the measured height of the adjacent cargo item by a predetermined distance; and
moving the individual cargo item to the unloading position using the moving device.

12. The method according to claim 11 , wherein the cargo bed is raised after the individual cargo item is moved to a position that is beyond the outer perimeter of the cargo bed in plan view.

13. The method according to claim 11 , wherein
the heights of the cargo items are measured using an image captured by a first detection unit positioned above the cargo bed, and
the positions of the cargo items in plan view are detected in an image captured by a camera.

14. The method according to claim 11 , wherein moving unit comprises a robot arm and a holding unit to hold the cargo items.

15. The method according to claim 11 , wherein the cargo group comprises cargo items having different sizes.

16. The method according to claim 11 , further comprising:
after moving the individual cargo item to the unloading position using the moving device, rotating the cargo bed in a direction such that a next cargo item to be unloaded becomes closer to the unloading position.

17. The method according to claim 11 , wherein the heights of the cargo items are measured using a laser range finder on a guide rail adjacent to the cargo bed.

18. An unloading system that unloads cargo items from a cargo group on a cargo bed, the unloading system comprising:
a cargo bed on which a cargo group can be disposed, the cargo group comprising a plurality of cargo items;
a cargo bed lifting and lowering mechanism configured to raise and lower the cargo bed relative to an unloading position for the plurality of cargo items;
a camera disposed above the cargo bed in a vertical direction and configured to acquire images of the cargo group on the cargo bed;
a robot arm configured to grasp an individual cargo item in the plurality of cargo items, lift the individual cargo item in the vertical direction, and move the individual cargo item in a horizontal direction to an unloading position;
a laser range finder on a guide rail adjacent to the cargo bed, the laser range finder being configured to translate along the guide rail in a vertical direction; and
a controller configured to:
determine heights of cargo items at an upper surface of the cargo group;
detecting positions of the cargo items in the cargo group in a plan view;
control the robot arm to grasp, lift, and move the individual cargo item according the detected positions and determined heights of the cargo items;
lower the cargo bed during the lifting of the individual cargo item; and
stop the lowering of the cargo bed once a detected height of a lower end of the individual cargo item being lifted is above a measured height of an adjacent cargo item which was adjacent to the individual cargo item within the cargo group by a predetermined distance.

19. The unloading system according to claim 18 , wherein the robot arm grasps the individual cargo item using vacuum.

20. The unloading system according to claim 18 , further comprising:
a rotation mechanism configured to rotate the cargo bed.

Assignees

• Toshiba Kk
• Toshiba Infrastructure Systems & Solutions Corp
• Toshiba Infrastructure Systems & Colutions Corp

Inventors

• Otsuru Yoshihide

Classifications

• B65G59/026

  with a stepwise upward movement of the stack · CPC title

• B65G47/244

  by turning them about an axis substantially perpendicular to the conveying plane · CPC title

• B65G2203/042

  Sensors · CPC title

• B65G2814/031

  Removing from the top · CPC title

• B25J11/00

  Manipulators not otherwise provided for · CPC title