Abstract: A pile hammer for driving down hollow piles from an upper end thereof includes a hollow pile cap adapted to rest and support the hammer on a upper end of the pile being driven. The cap has an anvil surface for receiving blows from a ram which is slidably disposed on a hollow tubular base extending downwardly from the pile cap and having a lower end portion extending into the hollow pile being driven below the level of the pile cap. The ram is slidable on an upper portion of the hollow tubular base and has an annular lower end face adapted to strike the anvil surface of the pile cap when the ram is released to drop from an elevated position above the pile cap. A ram lift system is provided in an upper portion of the hollow tubular base for lifting the ram to an elevated position a selected predetermined height above the pile for release to drop downwardly and strike a driving blow against the anvil surface on the pile cap.

Abstract: A vibratory hammer/extractor for use with elongated pilings and the like extended into the earth includes a clamping assembly for releasing and securing the hammer to an upper end portion of a piling extended into the ground. A vibratory exciter is mounted on the clamping assembly for generating vibratory forces to be imparted to the piling while clamped tightly, and a suspension device is provided for supporting the exciter and isolating the vibration thereof from a hammer supporting element such as a flexible cable extending downwardly from the boom of a crane. The vibratory exciter includes a hollow gear case having a lower end wall secured to the clamping assembly and at least one pair of eccentric weights mounted on shafts for rotation about an axis transversely of the clamped piling for imparting vibratory forces to the piling as the eccentrics are driven in rotation.