A turbine generator comprises an elongate member, a support structure, a turbine wheel and an electrical generator. The support structure comprises a shaft and supports the elongate member for rotation about a rotation axis. The turbine wheel attached to the elongate member. The electrical generator comprises a rotor and a stator, the rotor being attached to the elongate member and the stator being arranged around the elongate member. The elongate member is provided with a bore and the shaft extends through an end of the elongate member into the bore so as to support it for rotation about the rotation axis.

A brushless direct current (BLDC) motor assembly may include a wheel provided to receive and discharge outside air, and having a coupling region defined therein, a rotor fixedly coupled in the coupling region to be integrated in the coupling region, the wheel being rotated by torque generated according to rotation of the rotor by a magnetic force, and a stator generating a magnetic force by interacting with the rotor, and comprising a stator core, a coil, and an insulator disposed between the stator core and the coil for integral coupling with the stator core and the coil, in which the stator may allow the insulator to be coupled to the rotor after a shaft is fixed to the insulator.

A ratio W1/W2 of a circumferential width W1 of each of inclined hill portions G2 of a radial dynamic pressure generating portion G and a circumferential width W2 of each of inclined groove portions G3 is 1.2 or larger. And when an inner diameter of a bearing member is D, the circumferential width W2 of each of the inclined groove portions satisfies 0.2D≦W2≦0.4D.

A rotational slip ring assembly for an improved counter-rotating (CR) differential electric motor assembly is utilized to power an aircraft vehicle or fan for moving a gas and includes two oppositely rotating propellers that may be mounted to horizontal flight and vertical lift-off aircraft or a fan housing in spaces similar in size to mounting spaces for traditional motors having only one propeller and includes a hollow central shaft and slip ring assembly that is mounted either within, slight above, or total above oppositely rotating components and around the hollow central shaft.

A motor includes a stator, a rotor, and a bearing. The stator includes a shaft that extends in a vertical direction. The rotor is rotatable around the shaft. The bearing supports the rotor in a rotatable manner. The rotor includes a magnet, a case, and a tooth groove. The magnet is radially outward of the stator and opposes the stator in a radial direction. The case covers a radially outer end of the magnet. The tooth groove is provided in a radially outer surface of the case.

A power tool reduces performance deterioration. The power tool includes a motor, an output unit, a motor compartment, and a grip. The motor includes a rotor bearing and a rotor rotatable about a rotation axis extending in a front-rear direction. The rotor includes a rotor magnet, a core to which the rotor magnet is fixed, and a shaft protruding from an end face of the core and supported by the rotor bearing. The shaft and the core together are a single member. The output unit is at least partially located frontward from the motor and rotatable by the rotor. The motor compartment accommodates at least a part of the motor. The grip protrudes downward from the motor compartment.

An electric drive system including: a rotary motor system including a hub assembly, a first rotating assembly, a second rotating assembly, and a third rotating assembly, wherein the hub assembly defines a rotational axis about which the first rotating assembly, the second rotating assembly, and the third rotating assembly are coaxially aligned and are capable of independent rotational movement independent of each other; a multi-bar linkage mechanism connected to each of the first and third rotating assemblies and connected to the hub assembly and constraining movement of the hub assembly so that the rotational axis of the hub assembly moves along a defined path that is in a transverse direction relative to the rotational axis and wherein the multi-bar linkage mechanism causes the rotational axis of the hub assembly to translate along the defined path in response to relative rotation of the first rotating assembly and the third rotating assembly with respect to each other.

A method for arranging an electric machine on a transmission, having the steps of providing a stator housing, inserting a hollow cylindrical stator into the stator housing such that the stator is rotationally fixed in the stator housing, and aligning the stator housing with the transmission. Additional steps include securing the stator housing on the transmission, inserting a rotor having a rotor hollow shaft into the stator, securing the rotor to a transmission input shaft, placing a bearing shield having a bearing pin on a receiving opening of the stator housing such that the bearing pin engages in a rotor cavity of the rotor hollow shaft and in a pivotally attached bearing device arranged in the rotor cavity such that the rotor is mounted so as to be rotatable about the rotor longitudinal axis.

An energy conversion assembly including an input shaft coupled to a first annular gear through a first direction limiting device configured to allow rotation of the first annular gear in a first direction and substantially inhibit rotation of the first annular gear in a second direction. The input shaft may be coupled to a second annular gear through a second direction limiting device configured to allow rotation of the second annular gear in the second direction and substantially inhibit rotation of the second annular gear in the first direction. The assembly may include a first transmitting gear engaged with the first annular gear, a second transmitting gear engaged with the second annular gear, a conversion gear operatively coupled to the second transmitting gear, and a transmitting shaft coupled to the first transmitting gear and the conversion gear.

Provided is a motor including a shaft welded to or fused with a metallic member. The motor includes a shaft (5) made of metal and a base including a metal board (81) covered with a coating layer (83). The coating layer (83) has an opening (83b), and the metal board (81) includes a recessed part (84) exposed through the opening (83b). An outer peripheral part of the shaft (5) and the recessed part (84) are fused or welded together.