Automatic lock for extensible camera tripod leg

Claim 1

A locking arrangement for a tripod leg comprising: inner and outer telescopically related leg members with the inner member being nestably received with the outer member, said leg members including leg portions facing in opposition to each other; and opposed edge portions in the outer leg member defining an opening therein; support means in said opening including upright portions extending outwardly of the opening and further including retaining portions extending generally transversely relative to said upright portions and underlying said outer leg member adjacent said opposed edges and a lock member movably mounted between said upright portions, the lock member having a lock head including a lock portion and a release portion and being normally in engagement with the inner leg member; biasing means operatively interposed between the lock member and the outer leg member for normally urging the lock portion of the lock head against the adjacent surface of the telescopically related leg member in opposition to the leg portions of the leg members; relative telescopic movement of the leg members in one direction causing the release portion of the lock head to be presented in the area of normal engagement between the lock member and the adjacent leg member and telescopic movement of the leg members in a reverse direction causing the lock portion of the lock member to bear against the adjacent surface of the adjacent leg member and prevent such reverse movement between the leg memBers.