| 摘要 |
<p>The present invention relates to a reverse cut-off valve which has superior properties of cut-off and seal and adjustment or throttling. With respect to the existing cut-off valve, a straight duct portion with lower portion open is additionally provided at the lower part of the valve body (4) of the present valve, and the valve clack (7) is disposed under the valve seat (5), the medium enters into the valve body from the bottom of the valve seat, the lower part of the valve seat can be made to have a shoulder, and a circle projection may be provided on the peripheral of the valve clack to protect the valve clack, the valve rod (9) has a cone body which can control pressure and outflow, and the present valve adopts six kinds of valve rod up-down sliding mechanisms in which the valve rod can't rotate. Thus, the wear of the relating parts is reduced and the service life is prolonged, while the present valve may meet the needs of hand-press, foot-stood, hydraulic rapid open and automatic close. With this construction, the present valve has many advantages of simple construction, low cost, no leak, saving water and material, no electrical consumption, rapid open and close, long service life, convenient installation and maintenance, wide applications and so on, it can also bring notable economical and social benefit.</p> |
