Mine props
US5868527A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1997 |
| Grant date | Feb 9, 1999 |
| Priority date | — |
| Expiry date | May 22, 2017 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21D15/42
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The invention concerns a mine prop which has a cutting device and a cuttable plunger. The cutting device has a sleeve and a cutter which is fixed to the sleeve and which presents cutting edges transverse to the sleeve axis and axially oriented openings between the cutting edges. A vacant space exists in the sleeve beyond the cutting means. The cuttable plunger projects from the sleeve with at least a portion of the plunger extending within the sleeve to the cutter. When compressive loading applied to the mine prop is of sufficient magnitude to cause the cutting device and plunger to telescope together, the cutting edges of the cutting means cut axially through the cuttable plunger. The resulting segments of the plunger pass through the openings into the vacant space where they are restrained within the sleeve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.