Internal locking device for telescopic elements and method of making the same

An improved internal releasable locking device for telescoping tubular members wherein there is an outer telescoping member having an internal annular surface wherein the radii extending annularly therearound is equidistant from the central longitudinal axis of the member, and an arcuate locking cam element having an outer peripery generally complementary with the internal annular surface of the outer telescoping member and adapted to interfit within an inner telescoping member, the improvement comprising:

• at least one camming groove formed in and as a part of said inner telescoping member adjacent an end thereof;
• said groove having at least one surface spaced annularly inwardly of said outer annular surface that acts as a cam surface to cooperate with and move said arcuate locking cam in a direction radially outwardly from said groove whereby when said outer telescoping member is fitted over said locking cam element and said inner telescoping member, rotation of one of said telescoping members will cammingly urge said locking cam element into tight locking engagement against the internal annular surface of said outer telescoping member.