Automatic article feeding system

• US 5,868,545 A
• Filed: 06/04/1996
• Issued: 02/09/1999
• Est. Priority Date: 08/07/1987
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kasai, Shozo, Yasuhara, Masateru, Azuma, Yusaku, Tanita, Takeo, Arai, Mitsuo, Yamamoto, Toshihiro, Nikaido, Norio, Inaba, Ryohei
• Primary Examiner(s): Merritt, Karen B.
• Assistant Examiner(s): KRIZEK, JANICE LEE
• Application Number:
  US08/657,500
• Time in Patent Office: 980 Days
• Field of Search: 221/134, 221/228, 221/233, 414/277, 414/281, 414/331, 414/411, 414/786, 414/929, 901/6, 901/7
• US Class Current: 414/808
• CPC Class Codes: B23P 19/001 Article feeders for assembling machines screws or nuts being carried by a disposable strip or disc B25B23/045
• CPC Class Codes: B23Q 7/10 by means of magazines
• CPC Class Codes: B23Q 7/1494 using grippers
• CPC Class Codes: B65G 65/00 Loading or unloading of vehicles B65G67/00

Abstract

A method for stocking a plurality of containers in a stocking device and feeding one container at a time to a robot includes the steps of separately supporting each container in a vertically moveable frame and moving the frame to align a selected container at a drawing position. The selected container is withdrawn from the frame and a lid of a pallet on the withdrawn frame is removed. The articles are then supplied to the robot.

Claims

1. A method for stocking a plurality of containers in a stocking device, with each container including a pallet having a plurality of articles therein and a lid for detachably covering the pallet, and feeding one container at a time to a robot, comprising the steps of:

separately supporting each container in a vertically moveable frame having a plurality of shelves;

moving the frame to align a selected container at a drawing position;

drawing the selected container out of the frame to an article supply position;

removing the lid from the pallet of the selected container to access the articles therein; and

supplying the articles to the robot.

2. A method for stocking a plurality of containers as set forth in claim 1, further comprising the step of engaging the lid from below when the frame is moved to a position where the selected container is in the drawing position.

3. A method for stocking a plurality of containers as set forth in claim 1, further comprising the step of returning the opened pallet from the article supply position into the frame after the robot is supplied with the articles.

4. A method for stocking a plurality of containers as set forth in claim 3, further comprising the step of covering the pallet with the lid when the pallet is returned to the frame.

5. A method for stocking a plurality of containers, each retaining a plurality of articles, feeding one container at a time to a computer-controlled robot for manipulating the articles and assembling products with the articles, and supplying a base with the articles by means of a drawing table which receives a selected container, with each container having a supporting portion to be supported and an upper surface spaced a predetermined distance from the supporting portion, the base being supported so as to be fixed in a horizontal plane, and the drawing table being supported so as to be fixed in a horizontal plane, comprising the steps of:

separately supporting each container on a vertically movable frame having a plurality of spaced shelves;

moving the frame to a predetermined position to align the selected container with the drawing table;

drawing the selected container from the frame onto the drawing table; and

supplying the articles from the selected container on the drawing table to the base by actuating the robot to grasp an article in the selected container and transfer the article to the base.

6. A method for stocking a plurality of containers as set forth in claim 5, wherein each container includes a pallet retaining the articles therein and having a lid for detachably covering the pallet, and further comprising the step of removing the lid from the pallet to open the pallet when it is moved to a specified position.

7. A method for stocking a plurality of containers as set forth in claim 6, further comprising the step of returning the open pallet from the drawing position into the frame after supplying the robot with articles.

8. A method for stocking a plurality of containers as set forth in claim 7, further comprising the step of drawing out the pallet of the selected container as the lid is being removed.

9. A method for stocking a plurality of containers as set forth in claim 7, further comprising the step of engaging the lid with an arm extending in a transverse direction relative to the drawing direction of the pallet.

10. A method of stocking a plurality of containers as set forth in claim 7, wherein the pallet includes a flange portion with first and second recesses, and further comprising the steps of engaging the first recess to withdraw the pallet from the frame, and engaging the second recess to lift the lid.

11. A method of stocking a plurality of containers as set forth in claim 10, further comprising the step of engaging the second recess which is formed in a central portion of a side edge of the pallet.

12. A method for feeding articles from a feed source to a robot, comprising the steps of:

temporarily storing a plurality of containers, with each container including a pallet retaining a plurality of articles therein and a lid for detachably covering the pallet;

separating a predetermined container from the plurality of containers;

stocking a plurality of separated containers;

removing the lid from a pallet of a designated container disposed in a feeding position; and

supplying the designated container to the feeding position where the articles can be fed to the robot.

13. A method for feeding articles contained in a plurality of types of containers to a robot, with each container including a pallet having various receiving depths and a detachable lid for covering the pallet, comprising the steps of:

supporting each container separately on a plurality of shelves in a vertically moveable frame;

moving the frame to a predetermined position to align a selected container in a feeding position for the robot; and

removing the lid from the pallet of the selected container.

14. A method for feeding articles as set forth in claim 13, further comprising the step of engaging the lid of the pallet from below as it is moved to the feeding position.

15. A method for feeding articles as set forth in claim 14, further comprising the step of engaging the lid removed from the pallet and holding it above the pallet in the frame.

16. A method for feeding articles as set forth in claim 14, further comprising the step of placing lid engaging arms in a waiting position outside the periphery of the pallet and beneath an upper surface thereof.

17. A method for stocking a plurality of containers and feeding containers one by one to a robot for manipulating the articles and assembling products with the articles, and supplying a base with the articles by means of a drawing table which receives a selected container, with the base being supported so as to be fixed in a horizontal plane, and the drawing table being supported so as to be fixed in a horizontal plane, comprising the steps of:

retaining a plurality of one kind of article in each container;

separately supporting each container individually on a plurality of spaced shelves disposed inside a vertically moveable frame;

selecting a container retaining an article to be fed to the robot;

moving the selected container to a vertically fixed feeding position in alignment with the drawing table;

withdrawing the selected container from the frame onto the drawing table;

feeding the articles in the selected container on the drawing table to the base by actuating the robot to grasp an article in the selected container and transfer the article to the base; and

moving a next preselected container to be withdrawn to the feeding position as the robot is fed the articles in the selected container and assembles the workpiece.

18. A method for stocking a plurality of containers and feeding containers as set forth in claim 17, wherein a memory is used, and further comprising the steps of:

memorizing the types of articles held in the containers, the steps of an assembly operation using the memorized articles, and the step order for assembling the workpiece;

administering the total number of steps for assembling the workpiece;

searching for a position of a container to be next fed to the robot; and

calculating a distance between the feeding position and the position where the next selected container is positioned.

19. A method for stocking a plurality of containers and feeding containers as set forth in claim 18, further comprising the steps of:

judging whether the robot has been fed enough articles to complete assembly of the workpiece; and

moving the frame by the distance calculated to place the next preselected container in the feeding position if additional articles are needed.

20. A method for stocking a plurality of containers and feeding containers as set forth in claim 19, wherein after moving the frame the calculated distance, further comprising the steps of:

increasing the number of steps in the memory by one when it is determined that the article drawn from the container is not the final article used to assemble the workpiece; and

resetting the number of the step order to an initial number in the memory when the robot completes the assembly of the workpiece.

21. A method for feeding articles from a stocker which is a feed source to a robot for manipulating the articles and assembling products with the articles, and supplying a base with the articles by means of a drawing table which receives a selected container, with the base being supported so as to be fixed in a horizontal plane, and the drawing table being supported so as to be fixed in a horizontal plane, comprising the steps of:

stocking a plurality of containers in a vertically moveable frame having shelves for individually supporting the containers, with each container having a plurality of one kind of article stored therein;

moving the frame to align the selected container with the drawing table at a vertically fixed feeding position;

drawing the selected container from the frame onto the drawing table;

feeding articles from the selected container on the drawing table to the base by actuating the robot to grasp an article in the selected container and transfer the article to the base;

replenishing, when a container in the stocker becomes empty, the empty container with a container which contains articles of the type that the empty container contained; and

controlling the replenishing of the containers by determining when a container becomes empty.

22. A method for feeding articles from a feed source to a robot as set forth in claim 21, wherein the containers include a pallet retaining the articles therein and a lid for covering the pallet, and further comprising the step of opening the lid prior to feeding the container to the robot.

23. A method for feeding articles from a feed source to a robot as set forth in claim 21, further comprising the step of locking the containers in the frame before vertically moving the frame.

24. A method for feeding articles from a feed source to a robot as set forth in claim 21, wherein the containers include a pallet retaining the plurality of articles and a lid for covering the pallet, and further comprising the steps of:

opening the lid prior to feeding the container to the robot; and

locking the containers in the frame before vertically moving the frame when the lid is open.

25. A method for feeding articles from a feed source to a robot as set forth in claim 21, further comprising the step of controlling the replenishing of the container to exchange an empty container for a full container after the frame moves so that the container to be next fed to the robot is in the feeding position where it is withdrawn to the robot.

26. A method for feeding articles from a stocker which is a feed source to a robot for manipulating the articles and assembling products with the articles, and supplying a base with the articles by means of a drawing table which receives a selected container, with the base being supported so as to be fixed in a horizontal plane, and the drawing table being supported so as to be fixed in a horizontal plane, comprising the steps of:

stocking a plurality of containers in the stocker to supply the containers one-by-one, each container containing a plurality of one kind of article therein;

arranging the containers sequentially from top to bottom according to a feeding order in the stocker having a vertically moveable frame with a plurality of shelves;

vertically moving the frame to align a selected container with the drawing table at a vertically fixed feeding position;

drawing the selected container from the frame onto the drawing table;

supplying the articles from the selected container on the drawing table to the base by actuating the robot to grasp an article in the selected container and transfer the article to the base;

discriminating whether or not an empty container in the stocker is returned from the robot into an uppermost position of the frame;

moving the frame upwardly by a distance according to a height of the empty container when it is discriminated that the empty container is not returned from the robot; and

exchanging the empty container for a full container after the frame is moved upwardly by the distance.

27. A method for feeding articles from a feed source to a robot as set forth in claim 26, further comprising the steps of:

moving the frame upwardly when it is discriminated that the empty container is returned to the uppermost position of the frame; and

exchanging the empty container for a full container when the empty container is returned from the robot.

28. A method for feeding articles from a feed source to a robot for manipulating the articles and assembling products with the articles, and supplying a base with the articles by means of a drawing table which receives a selected container, with the base being supported so as to be fixed in a horizontal plane, and the drawing table being supported so as to be fixed in a horizontal plane, comprising the steps of:

stocking a plurality of containers in a vertically moveable frame having a plurality of shelves for independently supporting the containers, with the containers being randomly arranged in the frame regardless of a supply order;

moving the frame in a vertical direction to align a selected container with the drawing frame at a vertically fixed feeding position;

withdrawing the selected container at the feeding position onto the drawing table;

supplying the articles from the selected container on the drawing table to the base by actuating the robot to grasp an article in the selected container and transfer the article to the base;

detecting a first position of an empty container in the frame where the empty container is returned from the robot;

detecting a second position in the frame where a preselected container to be next fed to the robot is supported;

calculating a distance between the first and second positions;

moving the frame so that the container to be next fed to the robot is in the feeding position;

withdrawing the preselected container at the feeding position; and

replacing an empty container in the frame with a full container.

29. A method for stocking a plurality of containers and feeding one container at a time to a robot for manipulating the articles and assembling products with the articles, and supplying a base with the articles by means of a drawing table which receives a selected container, with the base being supported so as to be fixed in a horizontal plane, and the drawing table being supported so as to be fixed in a horizontal plane, with each container retaining a plurality of articles therein, comprising the steps of:

separately supporting the plurality of containers individually in a vertically moveable frame;

moving the frame vertically to align a selected container with the drawing table at a feeding position;

drawing the selected container from the frame onto the drawing table;

supplying the articles from the selected container on the drawing table to the base by actuating the robot to grasp an article in the selected container and transfer the article to the base;

locking all of the containers to the frame when the frame is moving; and

controlling the moving of the frame and the locking of the containers based on an operation program of the robot.

30. A method for feeding articles to a robot as set forth in claim 29, wherein the container includes a pallet retaining the articles therein and a lid for covering the pallet, and further comprising the steps of:

opening the lid of the pallet in the frame before feeding the container to the robot; and

controlling the frame to move when each of the containers are locked and covered by a lid.