Electric infinite-range load-sensing transducer
US4106370A · kind A · utility
Inventors
Key dates
| Filing date | Feb 9, 1977 |
| Grant date | Aug 15, 1978 |
| Priority date | — |
| Expiry date | Feb 9, 1997 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16B31/028
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A device for the sensing and the measuring of the axial tension stresses occurring within the bolt of a threaded fastening system under installation comprising a metallic, electrically conductive flat washer-like first member, and a metallic, electrically insulated flat washer-like second member; wherein the electrically insulating material of an anodic-oxide coating, which is grown onto the second member's electrically conductive aluminum base material, is used as an intervening solid supporting substance for the purpose of spacing the first and the second member's electrically conductive surfaces, through a predetermined distance from each other, to resist a current flow therethrough; wherein, due to the anodic-oxide coating's minute compressibility under varying light to severe compressive load conditions, a change in the oxide coating's electrical leak-resistance occurs, thus allowing a very minute, detectable current to flow between the first and the second member. The minute electric current is electronically detected, measured and displayed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.