Ballast cleaning machine with preliminary sifting conveyor

A ballast cleaning machine capable of receiving ballast including a waste component from the track, cleaning the received ballast and conveying the ballast, which comprises a machine frame, a ballast excavating and conveying chain mounted on the machine frame, the chain having a discharge end for the excavated and conveyed ballast, ballast screening apparatus arranged to receive the ballast from the discharge end of the chain and to separate the waste component from the clean ballast, a conveyor band system mounted below the screening apparatus for receiving the clean ballast component and redistributing it to the track, and an endless conveyor band mounted below the screening apparatus for receiving and conveying the waste component, wherein the improvement comprises an endless sifting conveyor band mounted between the discharge end of the chain and the screening apparatus, the sifting conveyor band having an upper stringer receiving the excavated and conveyed ballast from the discharge end and defining openings permitting a portion of the waste component of said ballast to pass through the sifting conveyor band, the sifting conveyor band being mounted directly above the endless conveyor band whereby the endless conveyor band receives the waste component from the screening apparatus and the portion of the waste component passing through the sifting conveyor band, and a drive connected to the sifting conveyor band for driving the band whereby partially cleaned ballast is conveyed by the sifting conveyor band from the discharge end of the chain to the screening apparatus.