Fall arrest device with blocking catch

fall arrest device tracker employee with a fixed rope (12) Safety and comprising a body (16) equipped with a restraint system (18) arranged to take an active locking position in case of fall well either an inactive unlocking position authorizing progression user along the rope (12) in the direction of the ascent, or in the opposite direction during a controlled descent, said restraint (18): - a carrier arm (26) articulated on a first axis (24) of the body (16), - a roller (28) shaped cylindrical wheel mounted rotating free on a second axis (30) integral with the support arm (26), - and a centrifugal coupling (38) arranged between a drive member (33) of the roller (28) and the support (26) arm, so that occupies a disengaged position or engaged position, characterized in that the centrifugal coupling (38) comprises at least one sprue (40) movable along a ramp (42) opposite a drag member (33) to a compression spring (46), and an intermediate contact surface (45) inserted inside a rim (44) cylindrical support arm ( 26) for transmitting the spring force of the spring (46) to the flyweight (40).