초록 ▼

An earth drain comprising a core consisting of an elongated flexible web having on at least one surface thereof, and preferably on both surfaces, an array of discreet projections spaced transversely across the width of the web, and longitudinally in the lengthwise orientation of the web. The array o

An earth drain comprising a core consisting of an elongated flexible web having on at least one surface thereof, and preferably on both surfaces, an array of discreet projections spaced transversely across the width of the web, and longitudinally in the lengthwise orientation of the web. The array of projections is interrupted by a plurality of elongated projection-free zones extending in the longitudinal direction of the web, and spaced transversely across the width of the web. A filter of sheet-like water permeable material encases the core, and is adapted to be maintained in spaced relationship to the web by the free ends of the projections thereon.

대표청구항 ▼

An earth drain comprising a core consisting of an elongated flexible web having on at least one surface thereof an array of spaced projections, each having a base end affixed to said web, and a free end spaced from said web, the projections of said array being evenly spaced in parallel rows extendin

An earth drain comprising a core consisting of an elongated flexible web having on at least one surface thereof an array of spaced projections, each having a base end affixed to said web, and a free end spaced from said web, the projections of said array being evenly spaced in parallel rows extending longitudinally and transversely of said web and a filter of sheet-like water permeable material encasing said at least one surface and adapted to be maintained in spaced relationship to said web by the free ends of said projections, characterized in that said array of projections is interrupted by a plurality of transversely spaced elongated projection free zones extending longitudinally of said web, the dimensions of said projection free zones in the transverse and longitudinal directions of the web being greater than the spacing between adjacent projections.