| 摘要 |
The tubular housing of the coupling piece incorporates a sepn. wall (26) dividing its interior into a first chamber (28) forming a first flow path (S1) between the first and fourth connections (14,20) and a second chamber (30) forming a second flow path (S2) between the second and third connections (16,18). There is an axial hole (32) in the wall between the two chambers, through which an axially adjustable valve spindle (40) extends. The spindle supports axially distributed O-ring seals (76,78,80,82) which, dependent upon the axial adjustment position of the valve spindle, seal against different valve seat surfaces (60,62,64,66) between the four connections (14,16,18,20). The spindle is capable of taking up four successive positions when it moves axially towards the third connection (18). Between the first and fourth connections (14,20) there is an internal axially extending threading (84), and the spindle (40) is firmly attached to an adjustable control (86) with limited axial extension. |
