US Patent 7178257 Tape measure with automatic blade extension mechanism

A tape measure includes an automatic blade extension mechanism. The tape measure allows a user to draw and lock a blade using only one hand, when measuring a dimension of an object, thus allowing the other hand to be freely used in a workplace where several operations must be carried out. Therefore, the tape measure allows the user to simultaneously perform a cutting operation, a hammering operation, a marking operation, etc. during the measuring operation. Thereby, the tape measure of this invention is convenient to use, and increases work efficiency.