Abstract: Lubricant oil (45) serving as second lubricant oil is supplied into an outer intermediate shaft (11c) by a lubricant oil supply unit (50) and accumulated therein, and thereby the lubricant oil (45) is supplied to a contra-rotating front seal unit (37). Thus, by bringing the front side of the contra-rotating front seal unit (37) (seal ring (37b)) into a wet state by the lubricant oil (45), it is possible to reduce heat generation and it is possible to extend the life of the contra-rotating front seal unit (37).

Abstract: The thrust load of an outer shaft is received by a contra-rotating thrust bearing provided in a boss of a front propeller and transmitted to an inner shaft. The combined thrust load of the outer shaft and the inner shaft is received by an inner thrust bearing provided on the bow side of the power transmission unit and transmitted to a ship body. The rotational force of an outer output shaft is transmitted to the outer shaft via a flexible joint (gear coupling). Thus, the thrust load of the outer shaft is transmitted to the ship body only via the inner shaft without being directly transmitted to the ship body, and the axial displacement and angular displacement are allowed by the gear coupling, so that it is possible to eliminate the influence of the change of hull deformation on the shaft center of the outer shaft.

Abstract: The object is to facilitate the installation of a contra-rotating propeller on a mother ship. Disclosed is a contra-rotating propeller unit in which a predetermined part on the rear side of an inner shaft (12) is supported by a contra-rotating rear bearing (36) provided in a boss (13a) of a front propeller (13), and which includes an inner fixing tool (50) detachably attached to a tip of an outer shaft (11) to temporarily support a predetermined part on the front side of the inner shaft (12), and a contra-rotating thrust bearing (40) provided in the boss (13a) of the front propeller (13) to receive the thrust load from the outer shaft (11) to transmit the thrust load to the inner shaft (12).

Abstract: The thrust load of an outer shaft (11) is received by a contra-rotating thrust bearing (40) provided in a boss (13a) of a front propeller (13) and transmitted to an inner shaft (12). The combined thrust load of the outer shaft (11) and the inner shaft (12) is received by an inner thrust bearing (41) provided on the bow side of the power transmission unit (20A) and transmitted to a ship body (2). The rotational force of an outer output shaft (24) is transmitted to the outer shaft (11) via a flexible joint (19) (gear coupling (19A)). Thus, the thrust load of the outer shaft (11) is transmitted to the ship body (2) only via the inner shaft (12) without being directly transmitted to the ship body (2), and the axial displacement and angular displacement are allowed by the gear coupling (19), so that it is possible to eliminate the influence of the change of hull deformation on the shaft center of the outer shaft (11).

Abstract: Lubricant oil (45) serving as second lubricant oil is supplied into an outer intermediate shaft (11c) by a lubricant oil supply unit (50) and accumulated therein, and thereby the lubricant oil (45) is supplied to a contra-rotating front seal unit (37). Thus, by bringing the front side of the contra-rotating front seal unit (37) (seal ring (37b)) into a wet state by the lubricant oil (45), it is possible to reduce heat generation and it is possible to extend the life of the contra-rotating front seal unit (37).

Abstract: The object is to facilitate the installation of a contra-rotating propeller on a mother ship. Disclosed is a contra-rotating propeller unit in which a predetermined part on the rear side of an inner shaft (12) is supported by a contra-rotating rear bearing (36) provided in a boss (13a) of a front propeller (13), and which includes an inner fixing tool (50) detachably attached to a tip of an outer shaft (11) to temporarily support a predetermined part on the front side of the inner shaft (12), and a contra-rotating thrust bearing (40) provided in the boss (13a) of the front propeller (13) to receive the thrust load from the outer shaft (11) to transmit the thrust load to the inner shaft (12).