Abstract: A device for clamping the adjustment ring 3 of a cone crusher with respect to a support ring 1 mated therewith by means of threads 2 comprises a check nut 4 and hydraulic cylinders 7 with spring-actuated piston rods 6 whose tips 8 are arranged in a groove 9, one of the surfaces of the groove being formed by a taper recess 5 of the clamping ring 4 and the other surface thereof being formed by the end surface 10 of the support ring 1. The piston rods 6 of the hydraulic cylinders 7 are arranged radially with respect to the axis of the check nut 4.