Work positioning device

• US 7,610,785 B2
• Filed: 07/10/2008
• Issued: 11/03/2009
• Est. Priority Date: 06/20/2001
• Status: Expired due to Fees

• Current Assignee: Amada Company Limited
• Original Assignee: Amada Company Limited
• Inventors: Sato, Jun, Takahashi, Tatsuya, Ishibashi, Koichi, Kato, Tetsuaki, Akami, Ichio, Kubota, Teruyuki
• Primary Examiner(s): Jones; David B
• Application Number:
  US12/170,505
• Publication Number:
  US 20090018699A1
• Time in Patent Office: 481 Days
• Field of Search: 72/173, 72/311.2, 723/891, 723/893, 724/19, 724/20, 724/22, 724/28, 724/61, 72/311, 72/311.1, 72/194, 901/6, 901/15, 901/46, 901/47, 700/229, 700/259, 198/468.2, 198/468.4, 414/225.01, 414/627, 414/781, 414/783, 414/784, 414/749.1, 414/751.1, 414/752.1
• US Class Current: 72/17.3
• CPC Class Codes: B21D 43/003 Positioning devices B21D28/04 and B21D28/265 take precedence; stops B21D43/26; centering moving strips B21D43/023
• CPC Class Codes: B21D 5/02 on press brakes without making use of clamping means

Abstract

Regarding predetermined positioning criteria (M₁, M₂), ((G₁, G₂), (N₁, or N₂), (K₁, K₂)), there is provided image processing means (40B) for obtaining by image processing, measured values (C_D1, C_D2) ((G_D1, G_D2), (N_D1, or N_D2), (K_D1, K_D2)) and reference values (C_R1, C_R2) ((G_R1, G_R2), (N_R1, or N_R2), (K_R1, K_R2)), and for moving a work (W) in a manner that the measured values (C_D1, C_D2) ((G_D1, G_D2), (N_D1, or N_D2), (K_D1, K_D2)) and the reference values (C_R1, C_R2) ((G_R1, G_R2), (N_R1, or N_R2), (K_R1, K_R2)) coincide with each other, thereby positioning the work (W) at a predetermined position.

Claims

1. A workpiece positioning device, for a bending machine, which positions a workpiece at a predetermined position by image processing, comprising:

an imager that photographs an entire image of only one corner of the workpiece supported by a gripper of a robot;

a workpiece image detector that obtains an entire detected corner image based on the entire image of only one corner of the workpiece which is photographed by the imager;

a workpiece reference image calculator that calculates an entire reference corner image based on pre-input information;

a difference amount calculator that compares the entire detected corner image and the entire reference corner image, and that calculates an amount of difference between the entire detected corner image and the entire reference corner image in an angular direction and in X and Y axial directions; and

a robot controller that controls, based on the amount of calculated difference, a robot such that the entire detected corner image and the entire reference corner image coincide at once with each other, in order to position the workpiece at the predetermined position.

2. The workpiece positioning device according to claim 1, wherein the imager comprises a single CCD camera.

3. A workpiece positioning device, for a bending machine, which positions a workpiece at a predetermined position by image processing, comprising:

an imager that forms an image of only one corner of the workpiece supported by a gripper of a robot by photographing the only one corner;

a workpiece image detector that obtains a detected corner image based on the image of only one corner of the workpiece which is formed by the imager;

a workpiece reference image calculator that calculates a reference corner image based on pre-stored data regarding a reference corner;

a difference amount calculator that compares the detected corner image and the reference corner image, and that calculates an amount of difference between the detected corner image and the reference corner image in each of an angular direction, an X axial direction and a Y axial direction; and

a robot controller that controls, based on the amount of calculated difference, a robot such that the detected corner image and the reference corner image concurrently coincide with each other, so as to position the workpiece at the predetermined position.