A plain bearing (410) is fixed to a shaft hole (401) of an impeller (400) of the pump (100) so as to rotatably support the impeller (400) with respect to the shaft (300), and is restricted from moving in an axial direction by an annular restrictor (310) fixed to the shaft (300). On an end face (411) of the plain bearing (410) facing the restrictor (310), a lubrication groove (412) connecting a radially inner side and a radially outer side of the end face (411) to supply cooling water onto the end face (411) for lubrication, and a dynamic pressure generating groove (413) that introduces a flow of cooling water created by rotation of the impeller (400) to generate a dynamic pressure, are provided. The present bearing suppresses an increase in rotation torque of the impeller (400) during high speed rotation.

An annular sliding component disposed at a relatively rotating position of a rotating machine and sliding relative to the other sliding component has a sliding surface provided with a dynamic pressure generation groove which includes a communication portion communicating with an external space and a dead-end portion on a relative rotation downstream of the communication portion. The sliding component includes a guide configured to guide a fluid existing in the external space on an upstream side of the communication portion in a guide direction different from a direction in which a peripheral surface of the sliding component formed on the downstream side of the communication portion and facing toward a side of the external space extends.

A bearing structure for an X-ray tube is provided that includes a journal bearing shaft with a radially protruding thrust bearing encased within a bearing sleeve, one of which rotates relative to the other. The stationary component, e.g., the journal bearing and/or the thrust bearing includes at least one vent groove formed therein that improves the ability of the journal bearing structure to enable gases trapped by the liquid metal within the bearing assembly to escape through the vent groove to the exterior of the X-ray tube. By adding a strategically located channel or vent groove of sufficient size in at least one of the journal bearing or the thrust bearing, the pressures resisted by the seal created between the liquid metal and the vent groove(s) in the bearing components is significantly reduced, allowing escape of the gases to avoid detrimental effects to the operation of the X-ray tube, while maintaining the load carrying capacity of the bearing assembly.

A semi-cylindrical half bearing for a sliding bearing includes at least one axial groove formed on its inner circumferential surface that includes a smooth groove surface formed back away from the inner circumferential surface toward a radially outer side of the half bearing. The groove surface forms a convex curve toward the radially outer side in a cross-section perpendicular to the axial direction of the half bearing, and forms a straight line extending in the axial direction in a cross-section parallel to the axial direction. The half bearing further includes a plurality of axial narrow grooves formed on the groove surface so as to be back away from the groove surface toward the radially outer side, that extend in the axial direction of the half bearing.

A thrust washer is provided with a ring-shaped portion that surrounds an insertion hole, the thrust washer is provided with a sliding surface and an oil groove configured to allow lubricating oil to flow in, the oil groove is provided with an opening portion configured to allow the lubricating oil to flow in from the insertion hole side in an inner peripheral end side, an outer periphery end side of the ring-shaped portion of at least one of the oil groove is provided with an oil stop wall which is configured to suppress flow of the lubricating oil toward an outer periphery side of the ring-shaped portion, and a sliding area ratio of each of the sliding surfaces to a projection plane in plan view of the ring-shaped portion is provided within a range of from 60% to 85%

A fluid-dynamic bearing system comprising a stationary bearing component (12, 16, 18) and a bearing component (14, 14a) rotatable about a rotation axis, wherein, during operation of the bearing, the stationary and rotary components are separated from each other by a bearing gap (20) filled with a bearing fluid, wherein at least one fluid-dynamic radial bearing (22, 24) and at least one fluid-dynamic thrust bearing (28) or, alternatively, at least one conical fluid-dynamic bearing are arranged along the bearing gap (20), and wherein the bearing gap (20) comprises first and second open ends sealed by a first sealing gap (34) and a second sealing gap (36). The second sealing gap (36) exclusively extends normal to the rotation axis (40).

A conical bearing member includes a communication hole communicating an inner peripheral surface and an outer peripheral surface of the conical bearing member, and the inner peripheral surface includes a press-fit region in contact with a shaft and an enlarged diameter region having a diameter greater than a diameter of the press-fit region and including an inner opening part of the communication hole. A tapered part having a diameter increasing toward the enlarged diameter region is provided at an end part of the press-fit region on the enlarged diameter region side.

A turbocharger includes: a bearing provided in a turbocharger body, and configured to rotatably support a turbine shaft in an insertion hole formed in the bearing; and an opposing portion which faces an end surface of the bearing in an axial direction of the turbine shaft. An end-surface guide portion is provided to any one of an opposing surface of the bearing which faces the opposing portion, and an opposing surface of the opposing portion which faces the bearing. The end-surface guide portion configured to make the insertion hole and an outer peripheral edge of the end surface of the bearing in radial directions of the turbine shaft communicate with each other extends forward in a rotational direction of the turbine shaft from a part of the end surface of the bearing which communicates with the insertion hole.

Provided herein, is an apparatus that includes a fluid dynamic bearing defined in a gap between a stationary component and a rotatable component. The fluid dynamic bearing includes a first portion of the gap at an axial end of the fluid dynamic bearing, and a second portion of the gap. The first portion of the gap is narrower than the second portion of the gap. A groove in the fluid dynamic bearing on the stationary component or the rotatable component includes a portion of a predetermined width or a predetermined depth. The portion of the predetermined width or predetermined depth is selected based on the first gap or the second gap.

As gantry speeds experienced in CT scanners increase, so too does the radial load force exerted on components attached to the gantry. A self-lubricating sliding bearing used inside a rotary X-Ray source of a CT scanner is particularly susceptible to increasing radial load force, because in operation, a self-lubricating bearing floats on a film of liquid lubricant. Thus, the radial load force will tend to act on the floating portion of the bearing to develop an eccentricity in the longitudinal axis of the floating portion of the bearing as compared to the longitudinal axis of the stationary part of the bearing. The eccentricity will eventually cause the floating portion of the bearing to contact the stationary part of the bearing in operation, thus limiting the load carrying characteristic of the self-lubricating sliding bearing. Accordingly, the present application proposes a modification to the design of a self-lubricating sliding bearing, in which the pumping pattern of the bearing is reduced or removed at special portions within the bearing, to thus compensate for the effect of the radial load force.