Automatic article feeding system

• US 5,232,331 A
• Filed: 03/13/1991
• Issued: 08/03/1993
• Est. Priority Date: 08/07/1987
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yamamoto, Toshihiro, Kasai, Shozo, Yasuhara, Masateru, Nikaido, Norio, Inaba, Ryohei, Azuma, Yusaku, Tanita, Takeo, Arai, Mitsuo
• Primary Examiner(s): Huppert, Michael S.
• Assistant Examiner(s): KRIZEK, JANICE LEE
• Application Number:
  US07/668,912
• Time in Patent Office: 874 Days
• Field of Search: 414/786, 414/926, 414/277, 414/281, 414/331, 414/411, 414/788.7, 414/929, 901/6, 901/7
• US Class Current: 414/802
• 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
• CPC Class Codes: Y10S 414/105 Shifted by article responsive means

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 The selected container is withdrawn from the frame and a lid of a pallet on the withdrawn frame is removed.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 feeding articles to a robot, comprising the steps of:

stocking a plurality of containers, each retaining a plurality of articles, in a stocker;

supplying containers one-by-one from the stocker to feed articles to the robot;

withdrawing empty containers from the stocker;

stacking the empty containers withdrawn from the stocker on an elevator;

detecting the thickness of the empty containers withdrawn from the stocker;

detecting the height of the stack of empty containers withdrawn from the stocker; and

calculating a descending amount of the elevator based on the detected thickness of the empty containers and height of the empty container stack.

2. A method for feeding articles to a robot as set forth in claim 1, further comprising the steps of:

discriminating whether the height of the stack is over a predetermined height limit based on a height which does not allow an empty container having a maximum height to be stacked on the stack of empty containers; and

discharging the stack of empty containers when the height of the stack is discriminated to be over the predetermined height limit.

3. A method for feeding articles to a robot as set forth in claim 1, further comprising the steps of:

storing in a memory information on the thickness of each container; and

detecting the thickness of the empty container by reading out the stored information.

4. A method for feeding articles to a robot as set forth in claim 1, wherein the containers have a plurality of thicknesses, and further comprising the step of detecting the thicknesses of the containers as the stack of empty containers descends.

5. A method for feeding articles to a robot as set forth in claim 1, wherein the container includes a pallet retaining articles therein and a lid for covering the pallet, further comprising the step of opening the lid of the pallet in the stocker before supplying the container to the robot.