A compressor includes a rotor configured to compress air and driven by a shaft. A motor is drives the shaft. The first and second journal bearings facilitate rotation of the shaft. The first journal bearing is upstream from the motor and the second journal bearing is downstream from the motor. The transfer tube is configured to provide cooling air from a bearing cooling air inlet to the first journal bearing. A method for cooling a compressor is also disclosed.

A compressor includes a rotor configured to compress air and driven by a shaft. A motor is drives the shaft. The first and second journal bearings facilitate rotation of the shaft. The first journal bearing is upstream from the motor and the second journal bearing is downstream from the motor. The transfer tube is configured to provide cooling air from a bearing cooling air inlet to the first journal bearing. A method for cooling a compressor is also disclosed.

According to one embodiment, there is provided a gas cooled electric rotating machine in which a cooling gas is flowed through into a rotor and a stator. The rotor includes a pair of center hole conductors inserted into a center hole along a center of rotation while being electrically insulated from a shaft and from each other, the center hole conductors including respective protruding parts protruding toward an end of the shaft. The rotor includes a pair of end conductors provided at the end of the shaft so as to be each electrically insulated from the shaft, the end conductors being electrically connected to side surfaces of the protruding parts of the pair of center hole conductors, the side surfaces serving as electric connection surfaces.

A magnetic field generating device includes a superconducting coil formed by winding a superconductive wire material; an unseparated conductor plate which includes an electric conductor and is placed such that the conductor plate is insulated from the superconducting coil and is adjacent to the superconducting coil in a winding axis direction of the superconducting coil, and one of main surfaces of the conductor plate faces the superconducting coil; and a protection circuit which is connected in parallel with the superconducting coil and attenuates a current flowing through the superconducting coil.

A magnetic field generating device includes a superconducting coil formed by winding a superconductive wire material; an unseparated conductor plate which includes an electric conductor and is placed such that the conductor plate is insulated from the superconducting coil and is adjacent to the superconducting coil in a winding axis direction of the superconducting coil, and one of main surfaces of the conductor plate faces the superconducting coil; and a protection circuit which is connected in parallel with the superconducting coil and attenuates a current flowing through the superconducting coil.

A strain wave gearing with a built-in motor is provided with a motor, a wave gear mechanism enclosing the motor coaxially, and a heat-insulation spacing formed therebetween. The wave gear mechanism has a wave generator attached to the motor rotor so as to rotate integrally with the motor rotor. A wave generator plug of the wave generator is fixed to a rotor magnet back yoke of the motor rotor so as to enclose the rotor magnet back yoke. The spacing is formed in a contact surface portion between the rotor magnet back yoke and the wave generator back yoke, whereby heat transfer from the motor to the wave gear mechanism is suppressed.

An electrical machine includes a stator containing bearing plates and windings conducting electrical current and the rotor. The stator has windings conducting electric current embedded in a composite material and shaped into winding segments forming a ring segment of an angular span constituting a part of the full angle. The segments are inserted between the external and internal discs of the rotor. The magnetic poles are embedded and magnetised towards the axial direction of internal discs. The poles are separated from each other with a spacing made of a non-magnetic composite material of the internal and external discs structure. Each external and internal disc has an external reinforcing ring, made of a non-magnetic composite material reinforced with fibres of strength exceeding 1 GPa, formed by winding the fibres together with resin on the cylindrical surface of the discs. The external discs have a ring closing the magnetic circuit.

An electrical machine includes a stator containing bearing plates and windings conducting electrical current and the rotor. The stator has windings conducting electric current embedded in a composite material and shaped into winding segments forming a ring segment of an angular span constituting a part of the full angle. The segments are inserted between the external and internal discs of the rotor. The magnetic poles are embedded and magnetised towards the axial direction of internal discs. The poles are separated from each other with a spacing made of a non-magnetic composite material of the internal and external discs structure. Each external and internal disc has an external reinforcing ring, made of a non-magnetic composite material reinforced with fibres of strength exceeding 1 GPa, formed by winding the fibres together with resin on the cylindrical surface of the discs. The external discs have a ring closing the magnetic circuit.

A rotating electric machine including a rotator including a small-angle rotator portion and a large-angle rotator portion respectively having different inter-magnet end angles, each being a plane angle formed between a line connecting one outermost peripheral-side end of a permanent magnet and an axial center of the rotator and a line connecting an outermost peripheral-side end of another permanent magnet and the axial center of the rotator. The rotator includes three layers of the small-angle rotator portion, the large-angle rotator portion, and the small-angle rotator portion, which are laminated in the stated order along an axial line of the rotator. Therefore, demagnetization due to a temperature rise of the permanent magnets is suppressed. In addition, a temperature distribution in the permanent magnets in the axial direction of the rotator is reduced.

A rotating electric machine including a rotator including a small-angle rotator portion and a large-angle rotator portion respectively having different inter-magnet end angles, each being a plane angle formed between a line connecting one outermost peripheral-side end of a permanent magnet and an axial center of the rotator and a line connecting an outermost peripheral-side end of another permanent magnet and the axial center of the rotator. The rotator includes three layers of the small-angle rotator portion, the large-angle rotator portion, and the small-angle rotator portion, which are laminated in the stated order along an axial line of the rotator. Therefore, demagnetization due to a temperature rise of the permanent magnets is suppressed. In addition, a temperature distribution in the permanent magnets in the axial direction of the rotator is reduced.