Abstract: Methods for constructing a borehole, in some examples, in the Earth's crust, may involve holding a drill head in the borehole by a linkage. The drill head may include a thermal device that causes material on a base of the borehole to be released from the solid phase via phase change. The released material may be removed in a direction of the Earth's surface. Further, the thermal device may be operated so that it generates a thermal output power high enough to predominantly sublimate material when transitioning out of the solid phase.

Abstract: A vibration damper for vehicles is described, the damper curve of which is required to be arbitrarily variable, to enable the damping to be adapted optimally to driving conditions. For this purpose, the invention has a vibration damper in which a regulating member actuable by an actuating device can be pressed with variable force against at least one spring washer of a valve closure element of a damping valve arranged in the damper piston. The contact pressure of the regulating member is arbitrarily variable and the regulating member can be pressed progressively against the spring washer of the valve closure element upon an increase of force in the radial direction.