Impact indicator

• US 9,116,058 B2
• Filed: 05/30/2012
• Issued: 08/25/2015
• Est. Priority Date: 06/10/2011
• Status: Active Grant

• Current Assignee: Shockwatch Incorporated (Media Recovery, Inc.)
• Original Assignee: Shockwatch Incorporated (Media Recovery, Inc.)
• Inventors: Branch, Clinton A.
• Primary Examiner(s): Smith, R. A.
• Application Number:
  US13/483,961
• Publication Number:
  US 20120312224A1
• Time in Patent Office: 1,182 Days
• Field of Search: 116/200, 116/203
• US Class Current: 1/1
• CPC Class Codes: G01L 5/0052 measuring forces due to impact G01L5/0061, G01L5/14 take precedence; impact testing of structures G01M7/08; impact testing of material G01N3/00
• CPC Class Codes: G01P 15/036 for indicating predetermined acceleration values
• CPC Class Codes: G01P 15/038 by using fluidic means

Abstract

According to one aspect of the present disclosure, a device and technique for impact detection is disclosed. The impact indicator includes a first member having a reservoir for holding an indicator fluid; and a second member couplable to the first member over the reservoir and configured to form a capillary gap between at least a portion of an interface between the first and second members. Responsive to receiving a predetermined level of impact, the indicator fluid moves from the reservoir to the interface between the first and second members and wicks into the capillary gap via capillary action, the indicator fluid disposed within the capillary gap providing a visual indication of the received predetermined level of impact.

Claims

1. An impact indicator, comprising:

a first member having a reservoir for holding an indicator fluid; and

a second member couplable to the first member over an opening of the reservoir and configured to form a capillary gap adjacent the opening and extending between opposing surfaces of the first and second members; and

wherein, responsive to receiving a predetermined level of impact, the indicator fluid moves from the reservoir to the capillary gap between the first and second members and wicks into the capillary gap via capillary action, the indicator fluid disposed within the capillary gap providing a visual indication of the received predetermined level of impact.

2. The impact indicator of claim 1, wherein a surface finish of at least one of the first member and the second member forms the capillary gap.

3. The impact indicator of claim 1, wherein the first member comprises a matted surface finish to form the capillary gap.

4. The impact indicator of claim 1, wherein the indicator fluid comprises water, ethylene glycol, lithium chloride and a colorant.

5. The impact indicator of claim 1, wherein the second member comprises a material enabling visibility of the indicator fluid when the indicator fluid is within the capillary gap.

6. The impact indicator of claim 1, wherein the indicator fluid comprises at least one of a synthetic hydraulic fluid, a silicone oil fluid and propylene glycol fluid.

7. The impact indicator of claim 1, further comprising a disc member, and wherein the capillary gap is formed between the disc member and the first member.

8. The impact indicator of claim 7, wherein the disc member comprises a flexible disc member.

9. The impact indicator of claim 1, wherein a diameter of the reservoir and a viscosity of the indicator fluid are selected to obtain a desired activation sensitivity for the predetermined level of impact.

10. The impact indicator of claim 9, wherein the viscosity of the indicator fluid is between 20 and 80 centistokes.

11. The impact indicator of claim 1, wherein the capillary gap is formed along a plurality of spoke members radiating outwardly from the reservoir.

12. The impact indicator of claim 1, wherein the capillary gap is sized to be between 0.001 and 0.005 inches.

13. The impact indicator of claim 1, wherein the capillary action causes the indicator fluid to migrate toward a peripheral boundary of the capillary gap.

14. An impact indicator, comprising:

a first member having a reservoir for holding an indicator fluid therein, the reservoir having a closed end and an open end; and

a second member couplable to the first member wherein at least a portion of the second member faces the open end of the reservoir; and

wherein, responsive to receiving a predetermined level of impact, at least a portion of the indicator fluid moves from the reservoir and contacts a boundary of a capillary gap interface located adjacent the open end of the reservoir and extending between opposing surfaces of the first and second members, the indicator fluid wicking into the capillary gap via capillary action, the indicator fluid disposed within the capillary gap providing a visual indication of the received predetermined level of impact.

15. The impact indicator of claim 14, wherein a surface finish of at least one of the first and second members forms the capillary gap.

16. The impact indicator of claim 14, further comprising a disc member located at least partially between the first and second members and extending over the open end of the reservoir, and wherein the capillary gap is formed between the disc member and the first member.

17. The impact indicator of claim 14, wherein the indicator fluid comprises at least one of a synthetic hydraulic fluid, a silicone oil fluid and a propylene glycol fluid.

18. The impact indicator of claim 14, wherein the indicator fluid when located within the capillary gap is visible through at least a portion of the second member.

19. An impact indicator, comprising:

a first member; and

a second member insertable into at least a portion of the first member, the second member having a reservoir for holding an indicator fluid therein; and

wherein, responsive to receiving a predetermined level of impact, the indicator fluid moves from an opening of the reservoir and wicks into a capillary gap formed and extending between opposing surfaces of the first and second members, the indicator fluid extending in at least two different directions within the capillary gap via capillary action, the indicator fluid disposed within the capillary gap providing a visual indication of the received predetermined level of impact.

20. The impact indicator of claim 19, wherein a surface finish of at least one of the first and second members forms the capillary gap.

21. The impact indicator of claim 19, wherein the indicator fluid when located within the capillary gap is visible through at least a portion of the first member.

22. The impact indicator of claim 19, further comprising a disc member located at least partially between the first and second members and extending over the reservoir, and wherein the capillary gap is formed between the disc member and the second member.

23. The impact indicator of claim 19, wherein the second member is sealably coupled to the first member to prevent the indicator fluid from exiting the impact indicator.