Abstract: Device for inhibiting relative movement between two articles in dependence on the speed of said movement comprises a box connected to one of said articles, a screw connected to the other article and mounted to slide freely in the box, and a nut rotatably mounted on the screw. If the screw is rapidly accelerated, the nut thereon is forced against a friction surface so that it cannot rotate, and this prevents further longitudinal movement of the screw. If, on the other hand, the screw moves slowly, the nut will turn on it, and permit continued movement by the screw.

Abstract: A shock and vibration insulator comprises an axial rigid element fastenable to an installation to be damped, a peripheral rigid element also fastenable to said installation and a radial rigid element extending radially between said elements and comprising a first radial part having an internal recess in the shape of an annular groove and a second radial part having a peripheral edge penetrating into said recess in which it can move radially so as to provide a fairly closed annular chamber.