Ventiloberteil

摘要

The upper part of a valve has a head piece (1), a spindle (2) and a valve piston (3). The valve piston moves axially in the head piece (1). The spindle (2) rotates in the head piece (1). Spindle (2) and valve piston (3) are connected by means of a motion screw thread (24, 32). The movement of the valve piston (3) in the axial direction is limited by a stop situated inside on the head piece (1) and a stop outside on the spindle (2) in the same cross-sectional plane. Two polyhedrons (31; 14) serve as axial guides, one on the valve piston (3) and one in the head piece (1); these polyhedrons are formed by cross-sectionally triangular teeth and they mesh. When the valve piston (3) is in the closed position, the sealing is done hydrostatically by means of a sealing ring (42) held in the head piece (1).