Tape rule blade

An improved tape rule blade, the forward extremity—as pulled out by its hook—of the tape rule blade consists of a standard radian and angle section, followed by a contiguous gradually decreasing radian and increasing angle sub-section, along which the cross-sectional radii and angles of curvature vary incrementally such that radii of curvature change from larger to smaller and the angles of curvature change from smaller to larger that is then followed on the standard radian and angle section by a contiguous decreased radian and increased angle sub-section that is next followed by a contiguous gradually increasing radian and decreasing angle sub-section, along which the cross-sectional radii and angles of curvature vary incrementally such that radii of curvature change from smaller to larger and the angles of curvature change from larger to smaller, resuming the original radius and angle of curvature across the forward extremity of the said tape rule blade;

• since the said standard radian and angle section at the forward extremity of the said tape rule blade is followed contiguously by a gradually advancing transitional section along which the cross-sectional radius and angle of curvature of the said tape rule blade changes, an extendible self-standing section is effectively constituted thereafter, which improves the blade of the tape rule by effectively increasing its total length of extension.