Abstract: This invention relates to a torque release coupling for use in drill strings comprising an outer string part (1) rotatably mounted outside a radially inner string part (2), and a rotation lock (3) positioned between them. The rotation lock (3) is coupled to a first of said string parts (1, 2) with a coupling device (4, 9) adapted to allow axial shifts relative to the first string part, and comprising axial gripping organs (5) adapted for releasable engagement with cooperating gripping organs in the second string part, the rotation lock (3) comprising a spring (6) or similar adapted to apply an axial force on the rotation lock (3) directed against the cooperating gripping organs (5) from the first string part.

Abstract: This invention relates to a torque release coupling for use in drill strings comprising an outer string part (1) rotatably mounted outside a radially inner string part (2), and a rotation lock (3) positioned between them. The rotation lock (3) is coupled to a first of said spring parts (1, 2) with a coupling device (4, 9) adapted to allow axial shifts relative to the first string part, and comprising axial gripping organs (5) adapted for releasable engagement with cooperating gripping organs in the second string part, the rotation lock (3) comprising a spring (6) or similar adapted to apply an axial force on the rotation lock (3) directed against the cooperating gripping organs (5) from the first spring part.