Power returning coilable tape rule - with improved connection between spring and blade provided by abutting shoulders on tongue of spring

摘要

The power returnable tape rule has an improved connection between the outer end of the power spring and the inner end of the slidable rule blade provided by an interchanging element. The rule blade has an elongated aperture adjacent its inner end with the margins of the blade defining the aperture including opposed inwardly extending finger portions. The tongue has spaced transversely extending shoulders facing in opposite directions. - It extends along the upper surface of the rule, downwardly into the aperture under the fingers and upwardly from the aperture and forwardly along the upper surface of the rule blade. The shoulders on the tongue of the spring abut the margins of the aperture adjacent the finger portions in either direction of relative longitudinal movement to limit such movement and retain the two elements in assembly.