An electromagnetic transducer, including a plurality of static flux paths, and a plurality of dynamic flux paths, wherein at least two of the plurality of static flux paths lie in respective first planes parallel and offset from one another, at least two of the plurality of dynamic flux paths lie in respective second planes parallel and offset from one another, and the first planes and the second planes are arrayed so as to establish at least a general tic-tac-toe lattice.

An electromagnetic transducer, including a plurality of static flux paths, and a plurality of dynamic flux paths, wherein at least two of the plurality of static flux paths lie in respective first planes parallel and offset from one another, at least two of the plurality of dynamic flux paths lie in respective second planes parallel and offset from one another, and the first planes and the second planes are arrayed so as to establish at least a general tic-tac-toe lattice.

A power tool includes a motor, a first power source access circuit, a first drive circuit, a second power source access circuit and a second drive circuit. The motor includes a rotor, a stator, a plurality of first-type windings and a plurality of second-type windings. The rotor is configured to rotate about a central axis. The stator includes a ring-shaped yoke portion, and a plurality of teeth. The plurality of first-type windings are configured to be wound around part of the plurality of teeth and the plurality of second-type windings are configured to be wound around other part of the plurality of teeth. The first power source access circuit is configured to access a first power source with a first voltage. The first drive circuit includes a plurality of first-type electronic switches connected between the plurality of first-type windings and the first power source access circuit. The second power source access circuit is configured to access a second power source with a second voltage. The second drive circuit includes a plurality of second-type electronic switches connected between the plurality of second-type windings and the second power source access circuit. The plurality of first-type windings and the plurality of second-type windings are spaced in a circumferential direction of the central axis.

A power tool includes a motor, a first power source access circuit, a first drive circuit, a second power source access circuit and a second drive circuit. The motor includes a rotor, a stator, a plurality of first-type windings and a plurality of second-type windings. The rotor is configured to rotate about a central axis. The stator includes a ring-shaped yoke portion, and a plurality of teeth. The plurality of first-type windings are configured to be wound around part of the plurality of teeth and the plurality of second-type windings are configured to be wound around other part of the plurality of teeth. The first power source access circuit is configured to access a first power source with a first voltage. The first drive circuit includes a plurality of first-type electronic switches connected between the plurality of first-type windings and the first power source access circuit. The second power source access circuit is configured to access a second power source with a second voltage. The second drive circuit includes a plurality of second-type electronic switches connected between the plurality of second-type windings and the second power source access circuit. The plurality of first-type windings and the plurality of second-type windings are spaced in a circumferential direction of the central axis.

A stator core including field slots housing field windings and armature slots housing armature windings is provided. Permanent magnets are housed in the respective armature slots. Field windings face to the permanent magnets directly or via the stator core on the outer and inner circumferential sides. A coil end of one of the armature windings straddles the predetermined one of the field slots and passes over the axial end face of each of the permanent magnets in the corresponding one of the field slots over which the coil end straddles.

A stator core including field slots housing field windings and armature slots housing armature windings is provided. Permanent magnets are housed in the respective armature slots. Field windings face to the permanent magnets directly or via the stator core on the outer and inner circumferential sides. A coil end of one of the armature windings straddles the predetermined one of the field slots and passes over the axial end face of each of the permanent magnets in the corresponding one of the field slots over which the coil end straddles.

Provided is a motor having an increased output. The motor includes: an armature including a plurality of non-wound teeth and a plurality of wound teeth having windings wound thereon, the teeth being circumferentially alternately arranged about an axis; and a field magnet including a plurality of magnets arranged side by side circumferentially so as to oppose one of an inner or an outer periphery of the armature, the field magnet being supported about the axis so as to be rotatable relative to the armature. The field magnet is provided with rotating force by sequentially switching a magnetic flux that flows through the non-wound teeth and the wound teeth due to energization of the windings of the armature. The wound teeth include a proximal-end portion having a circumferential width greater than a circumferential width of a proximal-end portion of the non-wound teeth.

Provided is a motor having an increased output. The motor includes: an armature including a plurality of non-wound teeth and a plurality of wound teeth having windings wound thereon, the teeth being circumferentially alternately arranged about an axis; and a field magnet including a plurality of magnets arranged side by side circumferentially so as to oppose one of an inner or an outer periphery of the armature, the field magnet being supported about the axis so as to be rotatable relative to the armature. The field magnet is provided with rotating force by sequentially switching a magnetic flux that flows through the non-wound teeth and the wound teeth due to energization of the windings of the armature. The wound teeth include a proximal-end portion having a circumferential width greater than a circumferential width of a proximal-end portion of the non-wound teeth.

A power tool includes a motor, a first power source access circuit, a first drive circuit, a second power source access circuit and a second drive circuit. The motor includes a rotor, a stator, a plurality of first-type windings and a plurality of second-type windings. The rotor is configured to rotate about a central axis. The stator includes a ring-shaped yoke portion, and a plurality of teeth. The plurality of first-type windings are configured to be wound around part of the plurality of teeth and the plurality of second-type windings are configured to be wound around other part of the plurality of teeth. The first power source access circuit is configured to access a first power source with a first voltage. The first drive circuit includes a plurality of first-type electronic switches connected between the plurality of first-type windings and the first power source access circuit. The second power source access circuit is configured to access a second power source with a second voltage. The second drive circuit includes a plurality of second-type electronic switches connected between the plurality of second-type windings and the second power source access circuit. The plurality of first-type windings and the plurality of second-type windings are spaced in a circumferential direction of the central axis.

A brush-commutated direct-current motor comprises a stator with a plurality of exciter poles, a rotor with a plurality of pole teeth, which is rotatable relative to the stator about an axis of rotation, grooves arranged between the pole teeth, and coil windings arranged on the pole teeth and a commutator which is arranged on the rotor and a plurality of lamellae to which the coil windings are connected. For manufacturing such direct-current motor the coil windings are arranged on the pole teeth in winding cycles, in each of which a coil winding is wound onto each pole tooth. It is provided that on each pole tooth a first coil winding wound around the pole tooth in a first winding direction and a second coil winding wound around the pole tooth in a second winding direction opposite to the first winding direction are arranged.