摘要:
A method of and a device for protecting an electric motor (4) in a pod unit (1) for propulsion of marine vessels against shaft bending shocks when the blades (2) of the pod propeller hit ice blocks or other hard objects, said motor (4) having a drive shaft (3), a rotor (41) and a stator (42), said shocks tending to momentarily bend the drive shaft (3) to such an extent that the rotor (41) will come into contact with the stator (42). In accordance with the present invention, the rotor (41) is prevented from coming in detrimental contact with the stator (42) by providing at least two members (61, 62), which together form a radial plain bearing (6) having mating arcuate bearing surfaces (611 and 621, respectively), which during normal operation of the motor (4) are spaced from one another by a gap and come in contact with one another only at extreme loads with short durations. One of the members (61, 62) is an inner member (61) having a circular circumference that constitutes one (611) of the bearing surfaces (611, 621). The arcuate bearing surface (611) of the inner member (61) is coaxial with the rotor (41) and rotary therewith, and at least one of the other members is an outer member (62), which fixed in relation to the stator (42) and has its arcuate bearing surface (621) coaxial there with.
摘要:
In a bearing unit (3) of a cable sheave (1) of a cableway system, the cable sheave (1) is arranged on a shaft (2) which is mounted in bearings (8, 9) in a bearing framework (4). An inner ring (10) or outer ring (11) of at least a first bearing (8) is connected to the shaft (2). The outer ring (11) or inner ring (10) of said first bearing is connected to an inner ring (13) or outer ring (14) of a second bearing (9) and is mounted in the bearing framework (4) via said second bearing (9).
摘要:
A bearing device for a high speed rotary shaft is provided with a functional bearing disposed on a shaft which is supported rotatably on a housing by a pair of bearings (5), and capable of supporting rotatably the shaft, a rotation sensor for detecting the speed of revolution of the shaft and a controller for changing the functional bearing to a shaft supporting state in response to a rotation detection signal from the rotation sensor representing that the speed of revolution of the shaft is above a predetermined level. When the shaft rotates at a low speed, the functional bearing is set to a free state and the shaft is supported at two points on the housing by the pair of bearings (5) alone. When the shaft rotates at a high speed, the functional bearing is operated so that the shaft is supported at three points on the housing to prevent the occurrence of deflection of the shaft.
摘要:
La machine tournante comprend un système de butée axiale (40) auto-éclipsable montée entre l'arbre tournant (10) de la machine et le carter (21) de celle-ci, avec une partie de butée translatable (5) immobile en rotation, une partie de butée tournante (6) montée sur la partie de butée translatable (5) à l'aide d'un palier (9) susceptible de transmettre des efforts axiaux vers la partie de butée translatable (5), un dispositif 3lexible (7) de grande raideur reliant au carter (21) la partie de butée translatable (5) de manière à permettre une translation de faible amplitude de la partie de butée translatable (5) le long de l'axe de l'arbre tournant (10), un organe (8) de transmission de la poussée axiale de l'arbre tournant (10) vers la partie de butée tournante (6), cet organe de transmission de poussée (8) étant conformé de manière à être en contact entre l'arbre tournant (10), et la partie de butée translatable, lorsque la machine est au repos, et à entraîner la partie de butée tournante (6) par l'intermédiaire d'un frottement purement statique lorsque la machine est en rotation et exerce une poussée axiale. Des moyens (101 à 103) permettent l'application d'un fluide de commande en contact avec le dispositif flexible (7), de telle sorte que la pression de ce fluide exerce sur le dispositif flexible (7) une force tendant à écarter de l'arbre (10) la partie de butée translatable (5), la partie de butée tournante (6) et le cas échéant l'organe de transmission de poussée (8) lorsque la pression du fluide véhiculé par la machine audit point donné dépasse une valeur prédéterminée.
摘要:
A hybrid shaft bearing (20), a wind generator comprising this hybrid bearing (20), use of the hybrid bearing (20) and a method of operating the hybrid bearing (20) is provided. The hybrid shaft bearing (20) comprises a hydrodynamic journal bearing (22) and a rolling bearing (24). Both bearings (22, 24) cooperate with a support structure (26) and rotatably support a shaft (28). To avoid contact between the sliding surfaces (73, 75) of the hydrodynamic bearing (22) the auxiliary rolling bearing (24) carries the load at low speed, e.g. during start-up and shut-down periods, by ensuring a minimum lubricating gap (71). The hydrodynamic bearing (22) takes over the bearing load when a certain speed of rotation is reached. Active supply of lubricant to operate the journal bearing (22) as hydrostatic bearing at low speed is not required. The bearings (22, 24) may be arranged in parallel or in series.
摘要:
A method of and a device for protecting an electric motor (4) in a pod unit (1) for propulsion of marine vessels against shaft bending shocks when the blades (2) of the pod propeller hit ice blocks or other hard objects, said motor (4) having a drive shaft (3), a rotor (41) and a stator (42), said shocks tending to momentarily bend the drive shaft (3) to such an extent that the rotor (41) will come into contact with the stator (42). In accordance with the present invention, the rotor (41) is prevented from coming in detrimental contact with the stator (42) by providing at least two members (61, 62), which together form a radial plain bearing (6) having mating arcuate bearing surfaces (611 and 621, respectively), which during normal operation of the motor (4) are spaced from one another by a gap and come in contact with one another only at extreme loads with short durations. One of the members (61, 62) is an inner member (61) having a circular circumference that constitutes one (611) of the bearing surfaces (611, 621). The arcuate bearing surface (611) of the inner member (61) is coaxial with the rotor (41) and rotary therewith, and at least one of the other members is an outer member (62), which fixed in relation to the stator (42) and has its arcuate bearing surface (621) coaxial therewith.
摘要:
Coast-down bearing apparatus and methods are provided. The coast-down bearing includes a plurality of segments each having a radius of curvature substantially equal to an outer radius of a shaft and spaced radially therefrom to define a clearance, with the plurality of segments being configured to receive the shaft when a magnetic bearing drops the shaft. The coast-down bearing also includes a plurality of slots disposed between adjacent ones of the plurality of segments.
摘要:
A rotor drive shaft assembly (32) for use in a centrifugation system. The rotor drive shaft (34) has a bearing material configured as a sleeve (38) and mounted on the inside wall (41) of a spindle hub (30) with a clearance (39) existing between the sleeve and a housing (36) that surrounds the lower base of the shaft. When the rotor and hub experience radial displacement at a critical speed, the sleeve makes contact with the housing in order to limit further radial displacement. Alternatively, the sleeve can be mounted on the outside of the housing with the clearance existing between the sleeve and the spindle hub, with the sleeve making contact with the spindle hub at the critical speed in order to limit further radial displacement. In another embodiment, a support tube is provided which surrounds the lower portion of the shaft with a clearance existing between the shaft and the support tube. When the shaft experiences radial displacement at the critical speed, the shaft makes contact with the support tube which limits further radial displacement.