Patent ID: 8029024

Claim:
A tube coupling comprising: a coupling body having an open ended throughway to receive a tube, a collet located in the open end of the throughway having a ring and a plurality of flexible arms extending generally axially of the ring into the throughway, the throughway having a tapered cam surface convergent towards said open end and the collet arms having heads at their distal ends for engaging both the cam surface and the tube extending through the collet into the throughway to be compressed against the tube by the cam surface with outward movement of the collet with respect to the throughway to secure the tube in the throughway, the coupling body having one or more apertures to enable the location of the tube inserted into the throughway to be viewed, and a collet lock rotatably mounted on the coupling body having one rotary position in which the lock holds the collet in an outward tube securing position and another rotary position in which the collet can move axially with respect to the throughway for release and engagement of the tube by the collet, wherein the collet lock comprises a sleeve encircling the coupling body, the sleeve being shaped to cover the one or more apertures on the coupling body in a collet locked position and to reveal the one or more apertures in a collet released position.