Locking mechanism for retractable tape

A retractable tape measure having a housing for a flexible measuring tape and an opening in the housing through which a portion of the tape extends with the remainder of the tape being coiled around a spring biased reel having a hub around which the tape is coiled and opposed annular ends on said hub retaining said tape coiled therearound, one of said annular ends having a serrated circular peripheral edge with about 100 to about 150 serrations, and a locking mechanism shiftably mounted on said housing movable into and out of engagement with said serrations on said reel, said locking mechanism including a fixture having a wedge shaped cam and a serrated member movable radially, by sliding movement of said wedge shaped cam, into and out of contact with the serrated reel, whereby when said locking mechanism is engaged further uncoiling of the measuring tape is prevented as said reel is locked against rotation.

A retractable tape measure having a housing for a flexible measuring tape and an opening in the housing through which a portion of the tape extends with the remainder of the tape being coiled around a spring biased reel having a hub around which the tape is coiled and opposed annular ends on said hub retaining said tape coiled therearound, one of said annular ends having a serrated circular peripheral edge with about 100 to about 150 serrations, a first locking mechanism shiftably mounted on said housing movable vertically in and out of frictional engagement with said tape, and a second locking mechanism shiftably mounted on said housing movable radially into and out of engagement with said serrated edges, said second locking mechanism having a plurality of said serrations thereon which when engaged with a plurality of serrations on at least one of said annular ends provides a positive lock for said tape coiled around said reel hub to prevent further withdrawal of the tape from said housing.