A centrifugal compressor for compressing a refrigerant vapour in a refrigeration cycle. The compressor comprises an impeller drive shaft supported by first and second radial bearings for rotation within the compressor housing and an impeller assembly including at least one centrifugal impeller wheel mounted on the impeller drive shaft to rotate with the impeller drive shaft. The first and second radial bearings are hydrodynamic fluid bearings in which the bearing fluid is the refrigerant vapour. The compressor further comprises a conduit for supplying a portion of the refrigerant vapour from the impeller assembly to the first and second fluid bearings.

Embodiments of a gas bearing for aircraft engines are provided herein. In some embodiments, a gas bearing may include a first shaft; a second shaft disposed concentrically about the first shaft; and a protrusion extending from at least one of an inner surface of the first shaft or the outer surface of the second shaft to form a gap between the first shaft and the second shaft.

A motor bearing system has: a slide bearing operable as a gas-lubricated bearing by gas supplied from a pump; a rolling bearing; and a controller. The controller controls the pump such that, when the motor rotation speed is equal to or higher than the first speed and is lower than the second speed, the slide bearing functions as a bearing that supports the rotary shaft and the slide bearing is operated as the gas-lubricated bearing, and when the motor rotation speed is equal to or higher than the second speed, the pump is stopped. In addition, even in the case where the motor rotation speed is equal to or higher than the second speed, the controller does not stop the pump when a radial load applied to the rotary shaft of the motor is equal to or larger than a predetermined value.

The turbomachine comprises a stationary casing with a rotating member configured to rotate about a rotation axis in the stationary casing. The turbomachine further includes a rotating balance drum, arranged for co-rotation with the rotating member. A stationary sleeve is arranged in a fixed relationship with the stationary casing and surrounds the balance drum. The stationary sleeve comprises a plurality of consecutively arranged sleeve sections. A fluid channel is defined by an outer surface of the balance drum and an inner surface of the stationary sleeve. Between at least one pair of sequentially arranged upstream sleeve section and downstream sleeve section an annular chamber is provided, fluidly coupled to the fluid channel. Shunt holes are arranged on the upstream sleeve section, each shunt hole having a shunt hole inlet on an inner surface of the upstream sleeve section, and a shunt hole outlet in the annular chamber.

A rheometer has a shaft, which is supported rotatably in a gas bearing. The gas bearing has a first bearing element (rotor) attached to the shaft and a second bearing element (stator) that surrounds the first bearing element (rotor) with a distance between the two, forming a bearing gap. At least sections of the second bearing element (stator) are made from a gas-permeable material, and gas is passed through them in such manner that a gas cushion is formed in the bearing gap, by which the first bearing element (rotor) and the shaft are supported without direct contact between the two. It is provided that the first bearing element (rotor) is also made from a gas-permeable material, at least in the areas that face the second bearing element (stator), and which the gas penetrates and forms a preferably static gaseous layer close to the surface as a result of the dynamic pressure or backpressure of the gas.

A centrifugal compressor for compressing a refrigerant vapor in a refrigeration cycle. The compressor comprises an impeller drive shaft supported by first and second radial bearings for rotation within the compressor housing and an impeller assembly including at least one centrifugal impeller wheel mounted on the impeller drive shaft to rotate with the impeller drive shaft. The first and second radial bearings are hydrodynamic fluid bearings in which the bearing fluid is the refrigerant vapor. The compressor further comprises a conduit for supplying a portion of the refrigerant vapor from the impeller assembly to the first and second fluid bearings.

A bearing includes a bearing pad for supporting a rotary component and a housing attached to or formed integrally with the bearing pad. The housing includes a flexible column extending towards the bearing pad for providing the bearing pad with an airflow. The column supports the bearing pad from a location inward of an outer periphery of the bearing pad along an axial direction of the bearing. With such a configuration, a resistance of the bearing pad along a radial direction of the bearing is less at the outer periphery than a resistance of the bearing pad along the radial direction proximate the column.

A bearing system for a control surface of a high speed flight vehicle includes a bearing configured to support the control surface, and a pressurized lubricant chamber containing a lubricant for the bearing. The lubricant contained in the lubricant chamber is in a first phase. The lubricant chamber is subject to heating by a heated aerothermal environment (an environment external to the high speed flight vehicle). The lubricant in the first phase, therefore, is configured to transition from the first phase to a second phase when the lubricant chamber is heated by the heated aerothermal environment. The lubricant in the second phase is configured to flow from the lubricant chamber to the bearing to lubricate and cool the bearing via a flow-based cooling effect.

The windings of an electric motor are used to reduce the loading of noncontact bearings through the application of an offsetting radial force. For aerodynamic gas bearings, this force may be converted to a torque force after sustaining levitation speeds have been obtained.

A slewing bearing providing a first ring, a second ring, the rings being concentric around a central axis (X1), at least one row of rolling elements arranged between the rings in order to form an axial thrust that can transmit axial forces, at least one row of rolling elements arranged between the rings in order to form a radial thrust that can transmit radial forces, and at least one sealing assembly arranged between the first ring and the second ring. The sealing assembly provides first sealing means being arranged outside second sealing means, an annular sealed chamber being defined between the first sealing means and second sealing means.