Method and apparatus for evaluating a component pick action in an electronics assembly machine

• US 20070003126A1
• Filed: 05/18/2006
• Published: 01/04/2007
• Est. Priority Date: 05/19/2005
• Status: Abandoned Application

• Current Assignee: CyberOptics Corporation (Nordson Corporation)
• Original Assignee: CyberOptics Corporation (Nordson Corporation)
• Inventors: Manickam, Swaminathan, Case, Steven, Konicek, John, Duquette, David, Rudd, Eric
• Application Number:
  US11/436,389
• Publication Number:
  US 20070003126A1
• Time in Patent Office: Days
• US Class Current: 382/141
• CPC Class Codes: H05K 13/0812 the monitoring devices being integrated in the mounting machine, e.g. for monitoring components, leads, component placement
• CPC Class Codes: Y10T 29/53178 Chip component
• CPC Class Codes: Y10T 29/53191 Means to apply vacuum directly to position or hold work part

Abstract

An electronics assembly apparatus with improved pick evaluation is provided. The apparatus includes a placement head having at least one nozzle for releasably picking up and holding a component. A robotic system is provided for generating relative movement between the placement head and a workpiece, such as a circuit board. An image acquisition system is disposed to obtain at least one before-pick image of a component pick up location and at least one after-pick image of the component pick up location. The before-pick image contains a plurality of image portions, having each image portion view the pick-up location from a different point of view, while the after-pick image contains a plurality of image portions, having each image portion view the pick-up location from a different point of view.

Claims

1. A pick and place machine for assembling a workpiece, the machine comprising:

a placement head having at least one nozzle for releasably picking up and holding the component;

a robotic system for generating relative movement between the placement head and the workpiece;

an image acquisition system disposed to obtain at least one before-pick image of a component pick up location and at least one after-pick image of the component pick up location;

wherein the before-pick image contains a plurality of image portions, having each image portion view the pick-up location from a different point of view; and

wherein the after-pick image contains a plurality of image portions, having each image portion view the pick-up location from a different point of view.

2. The pick and place machine of claim 1, wherein the before-pick image is obtained in a single imaging operation of the image acquisition system.

3. The pick and place machine of claim 1, wherein a first image portion of the before-pick image has a first point of view of the pick up location, and a second image portion of the before-pick image has a second point of view of the pick up location, and the first and second points of view are different.

4. The pick and place machine of claim 3, wherein the first and second points of view are separated by approximately ninety degrees.

5. The pick and place machine of claim 1, wherein the after-pick image is obtained in a single imaging operation of the image acquisition system.

6. The pick and place machine of claim 1, wherein a first image portion of the after-pick image has a first point of view of the pick up location, and a second image portion of the after-pick image has a second point of view of the pick up location, and the first and second points of view are different.

7. The pick and place machine of claim 6, wherein the first and second points of view are separated by approximately ninety degrees.

8. The pick and place machine of claim 1, and further comprising an illuminator arranged to backlight the component with respect to the image acquisition system.

9. The pick and place machine of claim 8, and further comprising illumination optics arranged to receive illumination from the illuminator and redirect the illumination proximate the component.

10. The pick and place machine of claim 9, and further comprising imaging optics arranged to focus a backlit image of the component upon the image acquisition system.

11. The pick and place machine of claim 1, and further comprising imaging optics arranged to focus a backlit image of the component upon the image acquisition system.

12. The pick and place machine of claim 1, wherein the machine is configured to provide a pick indication based at least in part upon analysis of the plurality of after-pick image portions.

13. The pick and place machine of claim 12, wherein the machine is configured to provide a pick indication based at least in part upon analysis of the plurality of before-pick image portions.

14. The pick and place machine of claim 1, wherein the machine is configured to provide a pick indication selected from the group consisting of:

partial tombstone, full tombstone, partial billboard, full billboard, corner, and absent.

15. The pick and place machine of claim 1, wherein the image acquisition system is also disposed to acquire component placement images to verify component placement on the workpiece.

16. A method of evaluating a component pick action in an electronics assembly machine, the method comprising:

obtaining a before-pick image of a nozzle, wherein the before-pick image includes a plurality of image portions with each image portion corresponding to a different point of view of the nozzle;

obtaining an after-pick image of the nozzle, wherein the after-pick image includes a plurality of image portions with each image portion corresponding to a different point of view of the nozzle; and

wherein each image portion in the after-pick image has a point of view that matches a point of view of an image portion of the before-pick image; and

wherein analysis of the image portions provides a pick indication.

17. The method of claim 16, wherein the machine is configured to provide a pick indication selected from the group consisting of:

partial tombstone, full tombstone, partial billboard, full billboard, corner, and absent.

18. The method of claim 16, wherein the plurality of image portions includes at least three image portions and at least one image portion has a magnification that is different than other image portions.

19. The method of claim 16, wherein each of the plurality of image portions of the after-pick image views the nozzle from a different point of view, and at least two points of view are separated by about ninety degrees.

20. An electronics assembly machine comprising:

a placement head for placing components upon a workpiece;

a robotic system for generating relative movement between the placement head and the workpiece; and

means for evaluating a pick action of the machine.