The device (1) has two springs (2) e.g. torsion springs, tensible or expandable along a spring axis, and curvedly sectionally extending around the spring axis. The springs include an active spring section (3), whose length is adjustable. The spring section extends between a force application point (6) and a bearing section (8) of the springs. The bearing section is guided in a spring bearing (4). The spring bearing is displaceably arranged along the springs for varying a position of the springs relative to the force application point. The spring has a round and/or rectangular cross-section.