Abstract: An externally threaded mandrel extends from one end of the inner tube of a pair of telescoping tubes and is staked thereto. A trifurcated collet threads on the mandrel whereby a conical exterior surface on the mandrel cooperates with a conical interior surface of the collet. Longitudinal ridges on the inner surface of the outer tube interlock with longitudinal grooves on the collet preventing relative motion between the outer tube and the collet while permitting longitudinal translation of the outer tube relative to the inner tube. Rotation of the inner tube in one direction advances the mandrel into the collet, with the interacting conical surfaces driving the furcate segments of the collet outward against the inner wall of the outer tube until a tight fit is produced. Friction between the collet and tube wall locks the tubes together. Reverse rotation of the inner tube withdraws the mandrel and releases the outer tube from the grip of the collet segments. The collet is made of a resilient plastic material.

Abstract: A positive cam lock for a pair of telescoping extension poles. The cam support is mounted to the inner pole and carries a coaxially rotatably mounted idler cam and an eccentrically rotatably mounted locking cam. The outer pole has a number of inwardly extending splines which engage corresponding grooves on the locking and idler cams. When the outer pole is rotated, the eccentric cam will rotate and lock the outer pole at a desired axial position with respect to the inner pole while the idler cam prevents misalignment. A key mounted to the locking cam rides in a keyway on the cam support for preventing over-rotation of the locking cam.