Vibrating forming shoe in a twin wire former

Claim 1

A twin wire former for forming a paper web from an aqueous stock of papermaking fibers comprising: a first travelling, tensioned, looped forming wire having a substantially horizontal run, a second travelling, tensioned, looped forming wire having a co-operating substantially horizontal run co-operating with said horizontal run of said first wire to form a sandwich of said first and second wires with said stock sandwiched therebetween, a forming shoe within the loop of said first forming wire, said forming shoe having a convex surface bearing against said first forming wire along a portion of said substantially horizontal run, means to mount said forming shoe, said means to mount including means for pressing said shoe against said first forming wire to deform said sandwich around said convex surface and force said first wire into substantial conformity with said convex surface and squeeze water from said stock through said second forming wire, said means for pressing including a first resilient means urging said convex surface against said sandwich and including a second resilient means counteracting said first resilient means, said second resilient means being adjustable to adjust the spring constant of said means for mounting said shoe, and means to vibrate said shoe with an amplitude and frequency such that travel of said first wire over said convex surface of said shoe is facilitated.