| 摘要 |
<p>The valve described is provided with a valve disc (7) mating with a valve seat (8), said disc carrying an inwardly-tapered deflection collar (12) which externally overlaps the cross-section of the valve seat (8). This deflection collar (12) serves as a help for the travel, in order to increase the forces which operate in the valve opening direction during deflection. The deflection collar (12) consists of an inner tapered section (13) and an outer tapered section (14) which is roughly identical in its angle of taper but which projects for the flow. Both tapered sections (13, 14) are linked with one another across the transition region by a middle section (15) which ensures a smooth transition. It has been found that with a continuously tapered configuration of the deflection collar the force/travel characteristic curve exhibits roughly in the first third of the travel a dip which tends to reduce the power. The middle section (15) which links the two tapered sections (13, 14) is arranged in the tapered region where this dip in power would arise in the case of a continually tapered deflection collar. As a result, the free flow cross-section undergoes a reduction in the increase of the flow cross-section in the region of the middle section (15).</p> |
