Rock bolt load sensor
US5392654A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 13, 1993 |
| Grant date | Feb 28, 1995 |
| Priority date | — |
| Expiry date | Oct 13, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L5/243
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A rock bolt load sensor assembly for use to determine the load on a nut screwed onto a bolt embedded in a rock face, the assembly comprising a plurality of spring washers arranged to be mounted on the bolt between the nut and a roof plate, and a sensor comprising an induction coil adapted to be, in use, placed around the washers, the sensor including an indicator coupled to the induction coil whereby in use, the spring washers define an air space which varies in dependence on the load on the bolt and the induction coil provides an electrical indication of variation of the air space and the indicator provides an indication of variation of the load on the bolt.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.