Abstract: A vibratory ram for ramming and/or drawing of ramming members, comprises at least two out-of-balance rotors, at least one motor and at least one transmission which drive the two out-of-balance rotors in synchronism in opposite directions, at least two unbalanced masses on each of said out-of-balance rotors, wherein each out-of-balance rotor has a first unbalanced mass disposed on a first shaft and a second unbalanced mass disposed on a second shaft, said first and second shafts being concentric and being rotatable about their common axis, and a phase adjusting device for altering the relative phase of the first and second shafts.

Abstract: A material compacting vibration machine provided with an imbalanced system having coaxial first and second independently rotatable shafts carrying first and second drive elements and a pair of unbalanced masses having third and fourth drive elements secured thereto with driving connections between the first and third drive elements and between the second and fourth drive elements, and a drive shaft selectively coupled to the first and second drive elements, wherein the four drive elements all are disposed on one side of the imbalanced system and are shielded by a cover.