In certain embodiments, a power generator has a rotor, a stator, a bridge rectifier, and one or more capacitors. The stator has one or more inductors that generate phased AC power when the rotor moves relative to the stator. The bridge rectifier, which is connected between the inductors and two output terminals of the power generator, converts the phased AC power into a DC output current at the two output terminals. The capacitors are connected to the inductors to electro-magnetically resonate when the rotor moves relative to the stator to increase peak amplitudes of the phased AC power and thereby increase the level of the DC output current. In certain applications, the increased. DC output current enables the power generator to charge a battery faster and more efficiently.

In certain embodiments, a power generator has a rotor, a stator, a bridge rectifier, and one or more capacitors. The stator has one or more inductors that generate phased AC power when the rotor moves relative to the stator. The bridge rectifier, which is connected between the inductors and two output terminals of the power generator, converts the phased AC power into a DC output current at the two output terminals. The capacitors are connected to the inductors to electro-magnetically resonate when the rotor moves relative to the stator to increase peak amplitudes of the phased AC power and thereby increase the level of the DC output current. In certain applications, the increased. DC output current enables the power generator to charge a battery faster and more efficiently.

An electric motor bicycle system with an electric motor driven gear adapted to drive a wheel gear coupled to a bicycle hub. The motor driven gear is coupled to the wheel gear with a chain. The chain may be tensioned with one or more tensioners, which allow for a tighter system geometry. The motor may be supported with a bracket adapted to mount to industry standard disc brake mounting interfaces. In some aspects, the motor driven gear is coupled to the disc mounting interface of a wheel hub. In some aspects, the electric motor bicycle system may also have a disc brake system integrated therein.

An electric motor bicycle system with an electric motor driven gear adapted to drive a wheel gear coupled to a bicycle hub. The motor driven gear is coupled to the wheel gear with a chain. The chain may be tensioned with one or more tensioners, which allow for a tighter system geometry. The motor may be supported with a bracket adapted to mount to industry standard disc brake mounting interfaces. In some aspects, the motor driven gear is coupled to the disc mounting interface of a wheel hub. In some aspects, the electric motor bicycle system may also have a disc brake system integrated therein.

An integrated stator assembly incorporated in an electric motor including a rotor that includes a plurality of rotor magnets, each rotor magnet of the plurality of magnets having a polar axis running from a rotor magnet south pole to a rotor magnet north pole. The assembly comprising a mandrel of dielectric material, wherein the mandrel includes a first cylindrical surface coaxial to an axis of rotation of the rotor, an upper edge, and a lower edge. A plurality of electrically conductive stator windings wound upon the mandrel, each winding of the plurality of windings including a plurality of turns traversing the first cylindrical surface, wherein each turn of the plurality turns further comprises a first upper section disposed on the first cylindrical surface, wherein the first upper section intersects the upper edge of the mandrel, and the first upper section forms a first angle to the axis of rotation.

An integrated stator assembly incorporated in an electric motor including a rotor that includes a plurality of rotor magnets, each rotor magnet of the plurality of magnets having a polar axis running from a rotor magnet south pole to a rotor magnet north pole. The assembly comprising a mandrel of dielectric material, wherein the mandrel includes a first cylindrical surface coaxial to an axis of rotation of the rotor, an upper edge, and a lower edge. A plurality of electrically conductive stator windings wound upon the mandrel, each winding of the plurality of windings including a plurality of turns traversing the first cylindrical surface, wherein each turn of the plurality turns further comprises a first upper section disposed on the first cylindrical surface, wherein the first upper section intersects the upper edge of the mandrel, and the first upper section forms a first angle to the axis of rotation.

An electric machine for converting between electrical and rotary mechanical energy includes a rotor journaled to rotate about an axis of rotation, and a stationary stator mounted adjacent to the rotor. The stator has a ferromagnetic backiron with a surface facing the rotor across a magnetic airgap and having windings applied in a winding pattern formed directly onto the stator backiron and adhered to its surface with a pre-applied tacky adhesive. The windings magnetically exert torque upon the rotor across the magnetic armature airgap in response to electric power applied to the windings. The rotor has permanent magnets that generate magnetic flux across the airgap and through the windings. The windings are comprised of pre-bundled multiple individually insulated conductor strands that are electrically connected in parallel but are electrically insulated from each other along their lengths inside said magnetic armature airgap.

A slot includes a coil housing portion having first and second side portions and a bottom portion. A first straight line connects first and second points which are boundaries between the bottom portion and the side portions. A slot opening has third and fourth points closest to the first and second side portions. A second straight line connects the first and third points. A third straight line connects the second and fourth points. A first region is surrounded by the first straight line and the bottom portion. A second region is surrounded by the second straight line and the first side portion, and is surrounded by the third straight line and the second side portion. A third region is surrounded by the three straight lines. Areas A1, A2 and A3 of the three regions and total cross-sectional areas S1, S2, S3 of coils therein satisfy (S1/A1)>(S2/A2)>(S3/A3).

A drive apparatus includes: a motor having a rotor and a stator core; a housing; and a first injection port to inject a refrigerant into the stator core. The stator core includes: a core body surrounding the rotor; and a fixing portion projecting radially outward from the core body and fixed to the housing. The fixing portion includes an upper fixing portion. The first injection port is lower than an end portion of the upper fixing portion. The upper fixing portion is on one circumferential side of the first injection port. The first injection port is open in a first direction facing a directly lower side or a second direction angled to the one circumferential side with respect to the first direction, and is facing a portion on the other circumferential side of a boundary with an end portion of the upper fixing portion on the other circumferential side.

A drive apparatus includes: a motor having a rotor and a stator core; a housing; and a first injection port to inject a refrigerant into the stator core. The stator core includes: a core body surrounding the rotor; and a fixing portion projecting radially outward from the core body and fixed to the housing. The fixing portion includes an upper fixing portion. The first injection port is lower than an end portion of the upper fixing portion. The upper fixing portion is on one circumferential side of the first injection port. The first injection port is open in a first direction facing a directly lower side or a second direction angled to the one circumferential side with respect to the first direction, and is facing a portion on the other circumferential side of a boundary with an end portion of the upper fixing portion on the other circumferential side.