Abstract: A hinge has a pivoting leaf (2) and a fixed leaf (3), a hollow axle (7) fixedly connected to the pivoting leaf and rotatably connected to first and second journal bearings (5-1, 5-2) of the fixed hinge leaf, a spiral torsion spring (8) arranged in the hollow axle. One end of the spring is fixed to the hollow axle and the other end of the spring is fixed to a worm wheel (9) that is arranged in the first journal bearing. An endless screw (6) resides in the first journal bearing and engages with the worm wheel. Rotation of the endless screw drives the worm wheel and the spiral torsion spring to rotate, thereby adjusting the tension of the spring.

Abstract: Hinge (1) with one pivoting (2) and one fixed (3) hinge leaf, with a physical hinge axle (7) similar to a hollow cylinder which is common to both hinge leaves (2, 3) with an imaginary mathematical axis (4). The hinge axle (7) is connected unmovably to the pivoting (2) hinge leaf and mounted rotatably on a journal bearing (5-1, 5-2), the body of which journal bearing is connected rigidly with the fixed (3) hinge leaf. In the hinge axle (7) a spiral torsion spring (8) arranged, the first (8-1) of whose two ends is connected unmovably to the hinge axle (7) and the second (8-2) of whose two ends is connected via a worm-gear unit consisting of a worm wheel (9) and endless screw (6) to the journal-bearing body of the journal bearing (5-1). The worm wheel (9) is arranged in the journal bearing (5-1) to rotate around the axis (4) of the hinge axle (7) and is fixed permanently to the second (8-2) of the two ends of the spiral torsion spring (8).