| 摘要 |
<p>A valve housing of a diaphragm valve has a first valve chamber (14), into which open a central channel (16) and first (15) and second (16) side channels. Valve seats (18, 19) are arranged in the housing, and a first diaphragm (21) is adapted to se al against at least one of the first and second valve seats. The first diaphragm (21) is adapted to be pressed against and released from the valve seats, thereby shutting and opening, respectively, passage between the central channel and the side channels. A second valve chamber (45), into which opens a fourth channel (48), communicates with the central channel (16) through an opening (46) in the housing. A third valve seat (49) is provided and a second diaphragm (52) is adapted to be brought into and away from sealing engagemen t with the third valve seat (49). The second diaphragm (52) is adapted to be presse d against and released from the third valve seat (49), thereby shutting and opening, respectively, passage between the fourth channel (48) and the central channel (16).</SDOAB ></p> |
