Patent ID: 6907676
Filing Date: 2005-06-21
Classification: G01B

Abstract:
1. A strengthened blade tape measure, comprising: a tape casing having a receiving cavity and a guider opening communicating with said receiving cavity; a retraction unit supported in said receiving cavity; and a ruler blade, having an inner end attached to said retraction unit and an outer end stopped at said guider opening, adapted to slidably fold between a storage position and a measuring position, wherein at said storage position, said ruler blade is retracted to receive in said receiving cavity in a coil flattened configuration manner via said retraction unit, and at said measuring position, said outer end of said ruler blade is slidably pulled to extend said ruler blade in a concave-convex configuration out of said receiving cavity through said guider opening, wherein said ruler blade has a width in said flattened configuration thereof having a dimension within a range of 41-42 mm, a height in said concave-convex configuration thereof having a dimension within a range of 9-12 mm, and a thickness thereof having a dimension at least 0.2 mm, such that said ruler blade is capable of standing out from said tape casing with a measuring length at least 10 feet in a self-sustaining manner so as to prevent said ruler blade from buckling by its own weight; wherein said ruler blade has a longitudinal central portion and two longitudinal side portions integrally extended from two sides of said central portion of said ruler blade respectively, wherein each of said side portions of said ruler blade has a curvature smaller than a curvature of said central portion of said ruler blade, wherein said central portion of said ruler blade has a width in said concave-convex configuration thereof having a dimension within a range of 20-22 mm, a height in said concave-convex configuration thereof having a dimension within a range of 3-4 mm.