Actuator assembly

An oil or gas well actuator assembly 1 comprising: a fixed member 10 having an axis; an actuating member 30 being moveable axially with respect to the fixed member; a plurality of open-ended recesses on one of the fixed member and the actuating member wherein each recess at least partially houses a canted coil spring 40a-d; a radially extending shoulder 31 on the other of the actuating member and the fixed member adapted to engage a canted coil spring within a recess; a support member 50 adapted to cover open ends of the recesses and being moveable axially into different axial positions with respect to the recesses to uncover open ends of different recesses in the different axial positions of the support member. The actuator assembly being in a valve and a method of actuating a tool in a well is also claimed. Covering the open end of a recess may be resist changes in configuration of the canted springs and a configuration change permitted by uncovering the recesses