| 摘要 |
There is provided screen apparatus comprising side walls having a lower edge portion configured to accept tubular screen support members. An upper edge extends from the inlet end of the side walls to an apex from which a declining edge extends to the foot of the side walls. The lower edge, upper edge and declining edge are each provided with edge stiffening. A torque tube is secured between the respective exciter mount castings, the torque tube and stiffened side wall being selected to provide that the first fundamental frequency mode greater than the exciter frequency is at least 2 Hz greater than the exciter frequency and the first fundamental frequency below the exciter frequency is at least 2 Hz lower than the exciter frequency. |
