To provide a hand-held power tool which is equipped with a motor and can be used in a normal driving mode for a tip end tool and also in driving modes other than the normal driving mode. A power tool in which a tip end tool is driven by a motor to thereby perform a predetermined machining process on a workpiece, wherein the motor is a dual rotor motor comprising: an inner rotor; an outer rotor; and a stator including a driving coil mechanism, with the inner rotor and the outer rotor being coaxially disposed.

To provide a hand-held power tool which is equipped with a motor and can be used in a normal driving mode for a tip end tool and also in driving modes other than the normal driving mode. A power tool in which a tip end tool is driven by a motor to thereby perform a predetermined machining process on a workpiece, wherein the motor is a dual rotor motor comprising: an inner rotor; an outer rotor; and a stator including a driving coil mechanism, with the inner rotor and the outer rotor being coaxially disposed.

A flywheel energy storage system incorporates various embodiments in design and processing to achieve a very high ratio of energy stored per unit cost. The system uses a high-strength steel rotor rotating in a vacuum envelope. The rotor has a geometry that ensures high yield strength throughout its cross-section using various low-cost quenched and tempered alloy steels. Low-cost is also achieved by forging the rotor in a single piece with integral shafts. A high energy density is achieved with adequate safety margins through a pre-conditioning treatment. The bearing and suspension system utilizes an electromagnet that off-loads the rotor allowing for the use of low-cost, conventional rolling contact bearings over an operating lifetime of several years.

The invention relates to a magnetic generator (1) comprising at least one rotary drive means (2) having an axle associated with an actuator system, the actuator system comprising at least one induction rotor (5) associated with the axle of the rotary drive means (2), the induction rotor (5) comprising magnetic inductor structures (6), the induction rotor (5) being associated with at least one induced rotor (7) comprising induced magnetic structures (8) configured so as to cooperate with the inductive magnetic structures (6) so that the inductive magnetic structures (6) driven by the induction rotor (5) cause the induced structures (7) and the induced rotor (6) to rotate, said induced rotor (6) being associated with an electric power generation means (9).

The invention relates to a magnetic generator (1) comprising at least one rotary drive means (2) having an axle associated with an actuator system, the actuator system comprising at least one induction rotor (5) associated with the axle of the rotary drive means (2), the induction rotor (5) comprising magnetic inductor structures (6), the induction rotor (5) being associated with at least one induced rotor (7) comprising induced magnetic structures (8) configured so as to cooperate with the inductive magnetic structures (6) so that the inductive magnetic structures (6) driven by the induction rotor (5) cause the induced structures (7) and the induced rotor (6) to rotate, said induced rotor (6) being associated with an electric power generation means (9).

A wind energy harvesting machine with three counter-rotating rotors in a duct is disclosed. The wind energy harvesting machine includes a tower, a duct, a counter-rotating generator with two rotary parts, and three groups of blades. The duct includes supporting static stators in front and rear and a static nose cone in the front. The counter-rotating generator has a main shaft and rotary interior and exterior parts to rotating in opposite directions. Three rotary blade groups including front and rear blade groups rotatable around the main shaft in the same direction, and a middle blade group rotatable in an opposite direction. The front and rear blade groups are displaceable axially along the main shaft and the middle blade group is fixed on the exterior part of the counter-rotating generator.

An electrical generator assembly including a central rotatable shaft (12) having a winding assembly (26) mounted thereto for rotation therewith, a rotatable permanent magnet assembly (28) surrounding the winding assembly (26) adjacent thereto and in use cooperating therewith to induce a current in the winding assembly (26), and a drive system (38, 138, 238, 338, 438) drivingly interconnecting the central shaft (12) and the permanent magnet assembly (28), the drive system (38, 138, 238, 338, 438) defining a relative rotational speed between the permanent magnet assembly (28) and the winding assembly (26) which is greater than an absolute rotational speed of the winding assembly (26). A method of powering an electrical system (22) on a rotating rotor blade (18) supported by a rotating mast (12) is also discussed.

An electrical machine and method for driving at least one ancillary device of a motor is provided wherein the electrical machine comprises a stator, configured to be rotated, and a rotor, rotatably mounted relative to the stator, coupled to the ancillary device. The speed of the rotor may be a function of the rotational speed of the stator and the frequency of a supply current supplied to the electrical machine and thus drives the ancillary device at a demanded load/speed.

A winding type permanent magnet coupling transmission device includes a permanent magnet rotor and a winding rotor that is coaxial with the permanent magnet rotor and capable of rotating relative to the permanent magnet rotor. An air gap exists between the permanent magnet rotor and the winding rotor. The winding rotor is connected to a control structure capable of regulating the current/voltage of the winding rotor. The control structure is capable of controlling the current or voltage of the winding rotor, so as to regulate the output torque of the transmission device, with no need to configure any corresponding mechanical execution mechanism. Therefore, the transmission device has a simple structure and small energy loss.

A propulsion system assembly is provided including a driveshaft and a plurality of electric motor modules. The driveshaft is rotatably mounted to a casing about a drive axis, the driveshaft including a first shaft end and an opposite facing second shaft end. The plurality of electric motor modules are in axially stacked relationship with one another with respect to the drive axis to define an electric motor module stack, each electric motor module being configured for transmitting a torque to the driveshaft when coupled thereto independently of at least one other electric motor module. Each electric motor module includes a controllable clutch arrangement for selectively coupling and decoupling the respective electric motor module with respect to the driveshaft to respectively enable and disable transmission of torque between the respective electric motor module and the driveshaft.