Abstract: An earth-working machine includes a mobile chassis, a turntable rotatably mounted on the mobile chassis, a carriage rotatably mounted on the turntable in eccentric relation thereto, an earth-working mechanism mounted on the carriage, a source of a fluid pressure, a pair of first and second fluid motors for rotating the turntable and the carriage, respectively, and a fluid rate synchronizer composed of a pair of third and fourth fluid motors interconnected by a common output shaft for discharging amounts of fluid under pressure at a predetermined ratio, the source being operatively coupled to the third and fourth fluid motors, the first and second fluid motors being operatively coupled to the third and fourth fluid motors, respectively, whereby the turntable and the carriage will be angularly moved about their own axes at a constant angular displacement ratio.

Abstract: An earth-working machine such as an excavator includes a mobile chassis having a support base on which an internal or external gear is fixedly mounted. A slider ring is mounted on the underside of a turntable with a hydraulic motor mounted thereon and having a drive pinion held in mesh with the internal or external gear. A carriage supporting an excavating mechanism has an internal or external gear fixed to the underside of the carriage and rotatably mounted on an annular holder fixed to the turntable. An intermediate shaft is rotatably journalled in at least one bearing mounted on the turntable and has a pair of pinions fixed thereto and held in mesh with the gears, respectively. Alternatively, an intermediate shaft may have a pinion held in driving mesh with the gear secured to the carriage and driven by another hydraulic motor mounted on the turntable through sprockets and a chain trained therearound.

Abstract: An earth-working machine includes a first internal gear fixedly mounted on a mobile chassis, a turntable coaxially rotatably mounted on the first internal gear, a carriage rotatably mounted on the turntable in eccentric relation thereto and having a second internal gear, an earth-working mechanism mounted on the carriage, a first hydraulic motor mounted on the turntable and having a first pinion held in driving mesh with the first internal gear for rotating the turntable about its own axis, a second hydraulic motor mounted on the turntable and having a second pinion held in driving mesh with the second internal gear for rotating the carriage about its own axis, and hydraulic driving devices for actuating the first and second hydraulic motors independently or in synchronism. The hydraulic driving devices may be controlled by an electric control system supplied with signals from angle detectors such as rotary encoders for detecting angular displacements of the turntable and the carriage.

Abstract: An earth-working machine such as an excavator includes a mobile chassis having a support base on which an internal or external gear is fixedly mounted. A slider ring is mounted on the underside of a turntable with a hydraulic motor mounted thereon and having a drive pinion held in mesh with the internal or external gear. A carriage supporting an excavating mechanism has an internal or external gear fixed to the underside of the carriage and rotatably mounted on an annular holder fixed to the turntable. An intermediate shaft is rotatably journalled in at least one bearing mounted on the turntable and has a pair of pinions fixed thereto and held in mesh with the gears, respectively. Alternatively, an intermediate shaft may have a pinion held in driving mesh with the gear secured to the carriage and driven by another hydraulic motor mounted on the turntable through sprockets and a chain trained therearound.