A heat transfer system is disclosed that includes a circulation loop of a heat transfer fluid that comprises a halocarbon. The circulation loop includes a compressor or pump that includes bearing rolling surfaces in contact with the heat transfer fluid. The bearing contact surface has a substrate a layer thereon that includes a polymer or oligomer having polar side groups and a tribofilm.

The present disclosure provides a compressor and an air conditioner having the same. The compressor includes: a main shaft with a convex portion and a slip sheet; a cylinder; and an air inlet and outlet device including a disk body and an air suction port including an outer side, an inner side and a connecting side located between the outer side and the inner side, wherein the outer side is overlapped with an inner wall of the cylinder or is located on the inner side of the inner wall of the cylinder, the inner side is overlapped with an outer wall of the convex portion or is located on the outer side of the convex portion, and the connecting side is overlapped with a side wall of the slip sheet or is located on the inner side of the side wall of the slip sheet.

A glass ball has a density of 2.3 to 3.2 g/cm.sup.3, a Young's modulus of 60 to 150 GPa, and an average coefficient of thermal expansion at 50 to 350 C. being 4010.sup.7 to 12010.sup.7/ C. The glass ball is formed of a glass material including, as represented by mole percentage based on oxides, 30 to 75 mol % of SiO.sub.2, 2 to 30 mol % of Al.sub.2O.sub.3, and 5 to 25 mol % of R.sub.2O, where R is at least one kind selected from Li, Na and K. The glass ball includes a compressive stress layer in a surface thereof.

A motor is configured to drive a centrifugal compressor. The motor includes a stator, a rotor, and a shaft. The shaft is supported by a pressure dam bearing (230,240). The pressure dam bearing is lubricated with a lubricant. The lubricant creates a lubricant wedge within the pressure dam bearing that exert an upward force on the shaft. The upward force causes an amount of vibration within the motor. The pressure dam bearing includes a pressure dam (232,242) configured to hold a portion of the lubricant and exert a downward force on the shaft. The downward force balances the upward force and reduces the amount of vibration within the motor, thus achieving greater hydrodynamic stabilization.

Two hybrid ball bearings and a compressor bearing arrangement with two hybrid ball bearings for a rotatable support of a rotor of the compressor versus a stator of the compressor. The two hybrid ball bearings are arranged face-to-face or back-to-back, are designed with an optimal axial clearance depending on the inner diameter of a ring-shaped inner raceway element one of the hybrid ball bearings respectively a pitch diameter of one of the two hybrid ball bearings for a long bearing life in connection with an optimal compressor operating performance.

A Hybrid ball bearing including an outer raceway, an inner raceway, and a plurality of balls arranged between the inner raceway and the outer raceway. The outer raceway and the inner raceway are made from bearing steel and have a first surface RMS roughness R.sub.q1. At least one ball of the plurality of balls is made from a ceramic material and has a second surface RMS roughness R.sub.q2. In a mint condition, the roughness of the raceways R.sub.q1 is 2 to 5 times higher than the roughness R.sub.q2 of the at least one ball, as well as a refrigerant compressor comprising such a hybrid ball bearing.

Aircraft cabin blower systems and methods of operating aircraft cabin blower systems are provided. One aircraft cabin blower system comprises: a cabin blower compressor having a contactless bearing arrangement; a transmission having a transmission output arranged to drive the cabin blower compressor, a first transmission input arranged to receive mechanical power from a gas turbine engine, and a second transmission input; a reversible variator arranged to receive power from the gas turbine engine and to output mechanical power to the second transmission input, the reversible variator operable to output in both forward and reverse directions of rotation; and a controller configured to control an output speed and direction of rotation of the reversible variator.

A sliding component has an annular shape with a fluid facing inside and outside of the sliding component and has a sliding surface relatively sliding with eccentric rotation, in which the sliding surface includes a land and a plurality of dynamic pressure generation mechanisms arranged in a circumferential direction, the dynamic pressure generation mechanism includes a shallow groove portion and a deep groove portion, the shallow groove portion communicates with the deep groove portion, and a communication passage providing a communication between the deep groove portion and either an inside space or an outside space of the sliding component is formed in the sliding component.

Disclosed are a magnetic bearing, a compressor and an air conditioner. The magnetic bearing includes a radial stator, wherein the radial stator has a plurality of stator teeth extending inwardly in a radial direction thereof; two axial stators are arranged on two axial sides of the stator teeth, respectively; and radial control coils are wound on the stator teeth, each radial control coil being located outside an area of the stator teeth covered oppositely by the two axial stators. The magnetic bearing, the compressor and the air conditioner can effectively reduce the degree of coupling between a radial electromagnetic control magnetic circuit and an axial electromagnetic control magnetic circuit, and reduce the control difficulty of the magnetic bearing.

A magnetic bearing is provided. The magnetic according to the present disclosure includes: a stator core disposed to surround a central axis; a plurality of bobbins coupled to the stator core; a coil wound around the bobbin; and a positioning member coupled to the plurality of bobbins and determining positions of the plurality of bobbins, and the positioning member has a circular shape centered on a central point.