Patent ID: 6450385
Filing Date: 2002-09-17
Classification: E21B,F16L

Abstract:
Annular clamping ring comprising a rigid annular base (2) which has an axis, and supporting, by support means, a coaxial ring-shaped assembly of jaws (4) parallel to the axis and mobile in diametral planes, the said support means comprising, on the one hand, a rigid annular body (3) surrounding the assembly of jaws (4), mobile in axial translation by means of controllable cylinder actuators (6) which connect it to the base (2), the jaws (4) being connected to the annular body (3) by at least two connecting rods (5) forming an articulated parallelogram, characterized in that the said support means also comprise long connecting rods (14) articulated on the base (2) and on the outside of the jaws (4) in a position which is almost the axial direction, such that the axial translation of the annular body (3) with respect to the base (2) causes a substantially radial and synchronized displacement of the assembly of jaws (4).