Plastics material mesh structures
US6423394B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 28, 1997 |
| Grant date | Jul 23, 2002 |
| Priority date | — |
| Expiry date | Jul 28, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24314
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
In order to provide wider biaxially-stretched geogrids having high primary direction (PD) strength, crotch-forming zones of a starting material which is at least 2.0 mm thick have protuberances (6). On strectching, PD orientation passes right through the junction (27) but the protuberance (6) causes the orientation ratio of the crotch edge to decrease significiantly as orientation enters the central part of the crotch edge. After a secondary direction stretch of at least about 1.5:1, the thickness of the central part of the crotch edge is not reduced by more than about 20%. The stretching does not reduce the thickness of any point along notional ridge lines (31) to such an extent that the ratio of finished thickness to starting thickness at that point mid-point. In the biax geogrid (25), the junction mid-point is significantly thicker than the PD is less than about 80% of the ratio of finished thickness to starting thickness of the junction strand mid-point. The thickest part of the crotch is greater than about 80% of the thickness of the mid-point of the junction (27). The junction (27) has a generally square or rectangular central zone with narrow projections (28) at the corners …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.