Abstract: Two clutches are disposed between a driving shaft and a driven shaft, in particular a first synchronous clutch which automatically engages when the driven shaft overtakes the driving shaft and a second synchronous clutch which automatically engages when the driving shaft overtakes the driven shaft. As long as there is no external intervention the two clutches mutually protect one another against unintentional engagement. The clutch arrangement can only be put into a ready or enabled position by the action of an external force. From the ready position, the paired synchronous clutches can effect a torque transmitting connection between a driving shaft and a driven shaft when their rotational speeds are synchronous.

Abstract: An engageable toothed or jaw clutch is disposed in each of two parallel power transmission paths of a reduction gear unit. One of the clutches is a self-engaging main clutch having a synchronizing device and the other is a subsidiary clutch without a synchronizing device. The engageable clutch splines or gearing of each clutch are helically toothed and have substantially no clearance or play. Both clutches are interconnected by a converter or actuating mechanism with substantially no play. The converter or actuating mechanism translates the engagement motion of the main clutch into an engagement option of the subsidiary clutch.

Abstract: A jaw or dog clutch which automatically engages when reaching rotational speed equilibrium possesses an axially displaceable clutch star which is rigidly connected for rotation by means of a first tooth system or set of gear teeth with a drive hub, however, is connected to be axially displaceable, and possesses a second tooth system or set of gear teeth which can be brought to mesh, by axial displacement of the clutch star, with a tooth system or set of teeth, of a power take-off hub. At the clutch star there is rotatably mounted a screw socket which is connected by means of a pair of coarse-pitch threads with the power take-off hub. The screw socket can be entrained in one rotational direction by the clutch star by means of a pawl blocking device.

Abstract: Both gas turbines of a drive system for marine vessels can be selectively connected by related first clutches with drive pinions and during so-called cruising travel, where only one drive unit or machine is operative, additionally via a gearing train with the related drive pinions. By means of speed reduction gearing the drive pinions drive two propeller shafts.

Abstract: An automatically engageable jaw clutch having a toothed drive hub, a toothed power take-off hub, and a clutch star which is axially displaceable in relation to the power take-off hub. The power take-off hub is mounted to be rotatable and inclinable with radial play at a bearing body rigidly connected with the drive hub. This radial play is smaller than the radial play between a screw socket, operatively connected with the power take-off hub, and the clutch star. The clutch star has a first tooth system and a second tooth system. The clutch star, in axial spacing from its first tooth system, has a guide surface which is essentially concentric with respect to its axis of rotation. In the disengaged condition of the jaw clutch this guide surface is centered at a corresponding guide surface of one of both hubs, yet in the engaged condition of the jaw clutch such guide surface is spaced from the aforementioned corresponding guide surface.

Abstract: An automatically engageable synchronous jaw clutch with hydraulic engagement-servo device, comprising a respective toothed drive and power take-off clutch half and a clutch star, which is guided to be axially displaceable by means of a first gear-tooth system upon one of the toothed clutch halves and can be engaged, by means of a second gear-tooth system, with the other clutch half. A screw socket controls, during clutching or engagement, the clutch star. This screw socket is in meshing engagement, by means of a pair of coarse-pitch thread means with one of the clutch halves and can be coupled, by means of a pawl blocking device with the other clutch half. The engagement-servo device contains a piston which entrains the clutch star, and the displacement of the piston, initiated by the screw socket, controls an infeed channel leading to a servo cylinder chamber of the servo device, in order to hydraulically augment the engagement of the clutch.