FRACTURE RING SENSOR

• US 20190316976A1
• Filed: 06/27/2019
• Published: 10/17/2019
• Est. Priority Date: 10/05/2017
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Bradbury, Jonathan D., Fry, Jonathan R., Kane, Michael R.
• Granted Patent: US 10,883,886 B2
• Time in Patent Office: Days
• CPC Class Codes: G01L 1/06 by measuring the permanent deformation of gauges, e.g. of compressed bodies
• CPC Class Codes: G01M 99/007 by applying a load, e.g. for resistance or wear testing G01M99/001 takes precedence; testing the elasticity of structures G01M5/00
• CPC Class Codes: H05K 2201/10151 Sensor

Abstract

Embodiments of the invention include a fracture ring sensor and a method of using the same to detect out of tolerance forces. Aspects of the invention include a product having a defined an out of tolerance force, a fracture ring sensor, and a mounting assembly coupling the fracture ring sensor to the product. The fracture ring sensor is patterned with a conductive trace and is manufactured to break when subjected to a predetermined amount of force. The predetermined amount of force is substantially equal to a percentage of the out of tolerance force of the product.

Claims

1. A method for forming a fracture ring for detecting out of tolerance forces applied to a printed circuit board, the method comprising:

providing a fracture ring comprising a first material;

configuring the fracture ring to break when subjected to a predetermined amount of force, the predetermined amount of force substantially equal to a percentage of an out of tolerance force of the printed circuit board;

patterning the fracture ring with a conductive trace; and

forming electrical contacts on opposite ends of the conductive trace.

2. The method of claim 1 further comprising mounting the fracture ring to the printed circuit board.

3. The method of claim 2 further comprising:

measuring electrical continuity along the conductive trace; and

determining that electrical continuity along the conductive trace has been terminated.

4. The method of claim 1, wherein the first material comprises a ceramic material, glass, or a fiber-resin composite material.

5. The method of claim 1, wherein configuring the fracture ring to break comprises adjusting a design thickness of the fracture ring based on the first material such that the fracture ring will break when subjected to the predetermined amount of force.

6. The method of claim 1, wherein configuring the fracture ring to break comprises designing the fracture ring to fracture at 99, 98, 95, 85, 70, 50, or 20 percent of the out of tolerance force of the printed circuit board.

7. The method of claim 1 further comprising pre-damaging the fracture ring to tune a break strength of the fracture ring.

8. The method of claim 7, wherein pre-damaging the fracture ring comprises distributing defects throughout the fracture ring.

9. The method of claim 7, wherein the defects comprise scoring lines.

10. The method of claim 1, wherein patterning the fracture ring with the conductive trace comprises a surface patterning.

11. The method of claim 1, wherein patterning the fracture ring with the conductive trace comprises embedding the conductive trace within the fracture ring.

12. The method of claim 1, wherein the conductive trace is a first conductive trace, and wherein patterning the fracture ring further comprises patterning the fracture ring with a second conductive trace.

13. The method of claim 12, wherein the first conductive trace and the second conductive trace comprise a same trace pattern.

14. The method of claim 12, wherein the first conductive trace and the second conductive trace comprise different trace patterns.

15. The method of claim 12, wherein the first conductive trace and the second conductive trace comprise different electrical contact positions.