An actuation mechanism for a brake with a brake cable which can be operated by an actuator via a spindle shaft and with a force sensor for determining the mechanical loading of the brake cable on application of the brake is known from DE 101 02 685 A1, in which the mechanical load on the brake cable via the actuator, decoupled from the brake cable, can be determined. The force sensor contains a spring screw arranged axially between the brake side end of the spindle shaft and a housing accommodating the actuation mechanism, of which the change in length on actuation of the spindle shaft to apply the brake is measured by a Hall chip within the spring screw and serves as a measure for the force exerted on the brake cable when the brake is applied.