Spiral flights for improved soil mixing and efficient boring for use on multi-shaft auger soil mixing apparatus
US5368415A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 1993 |
| Grant date | Nov 29, 1994 |
| Priority date | — |
| Expiry date | Feb 18, 2013 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/44
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An apparatus for constructing subterranean structures, soil-chemicals mixture or soil-agents mixture by using a multi-shaft auger machine to mix soil with a chemical hardener in situ. As the auger shafts of the multi-shaft auger machine penetrate the soil, spiral flights attached to the auger shaft above the initial auger blades assist soil in passing by supporting structures located between adjacent auger shafts. The spiral flights both assist in raising the soil beyond the supporting structures and also prevent reagglomeration of the soil prior to passing by the supporting structures. The spiral flights have a diameter less than that of the auger blades attached to the shaft below the spiral flights and have a connection ranging from 360 degrees to 720 degrees around the shaft. The use of the spiral flights within this location results in a reduction in the amount of energy needed to auger a borehole, thereby resulting in excess energy for a more homogeneous mixing of the chemical hardener in the soil through which the auger passes. In addition to the increase in efficiency because of the available energy, the spiral flights also directly increase the surface area of structures a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.