Abstract: The multiphase brushless AC electric machine comprises a stator frame having a surface provided with parallel slots and projections disposed alternately, each of the openings being substantially as wide as the widest width of the corresponding slot; and a rotor frame having a surface provided with permanent magnet means having respective surface sections facing the slots and projections. All of the surface sections of the magnet means produce a magnetic flux density having a component average amplitude B.sub.r (.theta.) perpendicular to the corresponding surface of the stator, which is substantially defined by the following equation:B.sub.r (.theta.)=M.sub.r (.theta.).multidot.L.sub.a (.theta.)/L.sub.v (.theta.)where L.sub.a (.theta.) is defined by the following equation: ##EQU1## where .theta. is a position angle in radians with respect to a reference position on the rotor frame; B.sub.r (.theta.) is the component average amplitude at the position angle .theta.; L.sub.v (.theta.

Abstract: A synchronous machine rotor has a progressive magnetic airgap and a constant aerodynamic airgap.

Abstract: A commutator assembly includes a plurality of commutator pieces for supplying an electric current from a brush fixed at a motor housing to a coil rotating together with a rotor shaft of a small motor, and a commutator holder of a plastic material fixed to the rotor shaft for supporting the commutator pieces. The commutator pieces are cut out of a commutator piece joint body which has a plurality of commutator pieces radially extending from a single temporary connection and is molded into the commutator holder during molding process.

Abstract: Low cost multi-pole motor constructions and related methods of manufacture are disclosed. The economic advantages inherent in the construction and manufacture of C-frame motors, including modified and improved C-frame or twin bobbin motor constructions, have been applied to a variety of different kinds of motors including two pole, four pole and six pole permanent split capacitor motors; four pole, six pole, and eight pole shaded pole motors; stepper motors; multi-pole switched reluctance motors including two pole, four pole, six pole, and other multi-pole switched reluctance motors; as well as various other types of multi-pole motors. Such modified and improved C-frame motor constructions include the mounting of electrically conductive coils on at least one pair of adjacent and spaced side legs on one or both sides of a multi-pole central portion. Related methods for manufacturing laminations used in such motors from an elongated strip of material are also disclosed.

Abstract: A flat linear motor has a single row of permanent magnets mounted upon backplate and an armature having non-overlapping flat coils encapsulated in a block of epoxy resin mounted upon an armature backplate comprised of a magnetic material and having anchoring recesses or protrusions. The armature backplate serves to provide magnetic circuits of low magnetic resistance in the flat linear motor thereby increasing a force generated by the linear motor. A length of the armature backplate is a non-integral number of a pitch length of the permanent magnets so as to reduce cogging. The three non-overlapping flat coils are comprised of square wire windings which provide increased thermal conduction. An embodiment of the invention employs software commutation wherein a position sensing device is used by a controller to determine a position of the armature from which a field polarity is found by means of a formula or a look-up table.

Abstract: An improved rotor construction of a cylindrical linear motor capable of more correctly adjusting locations of the core groups and coils of the rotor and correctly affixing the core groups and the coils thereof using support plates which includes a plurality of core groups, disposed at a predetermined angle from each other and each having a plurality of teeth and a plurality of grooves formed therein; a plurality of disk type coils respectively inserted into the grooves; support plates disposed between the core groups; a first motor cover affixed at one end of the core groups and a second motor cover affixed at the other end of the core groups.

Abstract: Disclosed herein is a compact motor with a speed reducing mechanism, including a cylindrical casing having an open end, a stator fixedly provided in the casing, an exciting coil provided in the casing, a rotor provided in the casing and having a high-speed output shaft on which a pinion is fixed, a cover for covering the open end of the casing, a low-speed output shaft projecting from a hole formed through the cover, and a reduction gear train interposed between the pinion and the low-speed output shaft for transmitting power to the low-speed output shaft. The compact motor further includes a lever connected to the low-speed output shaft; an eccentric cylinder formed integrally with a final gear of the reduction gear train and adapted to eccentrically rotate about a gear shaft for rotatably supporting the final gear; and a connecting member having one end pivotally engaging with an outer circumference of the eccentric cylinder and another end pivotally engaging with the lever.

Abstract: In an alternator for a vehicle having field coils for generating rotating magnetic field and stator coils for generating alternating current voltages in response to the rotating magnetic field, each of three stator coils are wound on only one of three stator teeth provided equi-angularly in a two pole-pitch of the rotor so that coil ends of the stator coils exposed outside the stator teeth do not cross each other. Thus, all the coil ends are cooled equally by the cooling air and a temperature rise of the stator coils is minimized. In order to reduce magnetic noise the stator coils are grouped. The first group of coils are provided in contact with a stator core and a second group of coils. The first and second group of coils are shifted from each other by .pi./3 radian in electrical angle.

Abstract: A wheel motor for a vehicle is provided in which an electric motor is arranged in a central space defined in a wheel, to rotatably drive the wheel. A gear reducer is also arranged in the central space of the wheel, which has a plurality of gears including a final stage gear having an axial through hole formed therein. The electric motor includes a housing fixed to the vehicle body, a stator secured to the housing, a rotor rotatably fitted in a central space defined in the stator to generate the rotative driving force during rotation thereof, and an output shaft connected to the rotor through the gear reducer as well as to the wheel to be rotatively driven by the rotor, for transmitting the rotating output from the rotor through the gear reducer to the wheel. The output shaft extends through an axial through hole formed in the final stage gear of the gear reducer and an axial through hole formed in the rotor, and is rotatably supported by opposite end portions of the housing.

Abstract: A can body maker wherein the redraw sleeve is provided with an plurality of air escape openings to provide for the passage of air as the ram moves through the redraw sleeve and wherein the redraw sleeve is attached to the armature of a linear motor which includes a generally cylindrical armature which moves within a surrounding, coaxial stator. The armature includes a plurality of axially spaced apart armature salient pole rings separated by permanent magnet rings. The stator includes a plurality of axially spaced apart stator salient poles which each form a ring radially spaced from and surrounding a portion of the armature. The axial spacing between adjacent stator salient pole rings is one-third greater than the axial spacing between the armature salient pole rings, and an electromagnetic coil extends circumferentially within the stator around the armature between each stator salient pole ring.

Abstract: In an alternator for a vehicle having a field coil for generating rotating magnetic field and stator coils for generating alternating current voltages in response to the rotating magnetic field, the stator coils are grouped and wound in a dual winding system. In order to reduce magnetic noise, a first group of coils are provided in contact with a stator core and the second group coils. The first and second group of coils are shifted from each other by .pi./3 radian in electrical angle.

Abstract: An object of the present invention is to provide a novel stator structure in an electrical rotating machine which has a stator to one end of which an end plate provided with a bearing is fixedly mounted and a rotor rotatably supported by the bearing, in which unwanted metal particles produced during welding of the end plate to the stator are prevented from entering between the stator and the rotor.Positioning protrusions 61 are formed extending axially from the one end of the stator and positioning apertures 71 are provided in the end plate 65 for corresponding to and engaging with the positioning protrusions 61. Also, welding projections to be melted by resistance welding are arranged as located substantially on straight lines respectively extending from the rotation shaft 67 across the positioning protrusions 61 and on the outer side of the positioning protrusions 61. The end plate 65 is joined to the one end of the stator by welding at welding points 14.

Abstract: The invention is directed to a device for converting a circular motion into a reciprocating motion, which provides for improved guiding of a drive pin arranged on an eccentric within a slide slot of a drive member. The slide slot is bounded by at least two flexurally elastic portions whose respective first end is not deflectable by the drive pin, whilst the area towards the respective second end is deflectable. The two portions extend parallel to each other in opposite directions.

Abstract: An electric micromotor comprising a stator winding, a rotor magnet (11) mounted for rotation about a rotor axis (13) and having permanent-magnet poles facing the stator winding, and electrical connection means for the electrical connection of the stator winding to a power source. The stator winding is formed by a cylindrical body (1) having an electrically conductive cylindrical wall (3) provided with longitudinal slots, which extend from an axial end face (15) of the cylindrical body over at least a part of the length of this body, to bound and form axially extending electrical conductors (5) for cooperation with the permanent-magnet poles. The conductors are mechanically interconnected by electrically insulating reinforcement means (19) at the location of the longitudinal slots.

Abstract: A universal motor (18) for a power tool (10) has a stator assembly (22) and an armature (24). The stator assembly includes a plurality of interconnected field windings (28-34) to which current is supplied to run the motor. The armature has a commutator (36) including brushes (40a, 40b) for circulating current through the armature. To quickly and safely brake the motor, without excessively damaging the brushes, a switch (16) is interposed between an AC power source for the motor and the armature. In one embodiment, the switch shorts the armature during braking. In this embodiment, the switch includes sets (56, 58, 60) of electrical contacts by which the inner field windings (28, 30) are connected in series with the outer filed windings (32, 34); and the field windings are series connected with the armature.

Abstract: A bearing device with a primary and secondary magnetic fluid seal for use in a motor. A shaft and a frame in the motor are interconnected by a bearing. A magnetic fluid is placed in a region between the shaft and frame. The primary magnetic fluid seal is positioned above the bearing and the secondary magnetic fluid seal is positioned above the primary magnetic fluid seal to form a two-layered seal.

Abstract: A dynamic pressure air bearing type electric motor includes a motor casing comprising a base having a bearing cylinder and a cover which is attached to the base to cover the bearing cylinder. A rotor assembly is enclosed in the motor casing and has a rotational shaft inserted and held in the bearing cylinder for rotation. The rotational shaft has at least one pair of herringbone grooves formed in the outer circumferential face. A bearing gap is defined between the rotational shaft and the inner circumferential face. A bearing gap is defined between the rotational shaft and the inner circumference of the bearing cylinder. The base has an air flow path formed therein. Upon rotation of the rotor assembly, air is caused to flow through the bearing gap axially along the rotational shaft.

Abstract: In a non-commutating-pole commutator motor, in particular as the drive of a power hand tool, a device for reversing the direction of rotation includes a switch (8) for reversing the direction of current in the rotor winding, and a brush apparatus (4) mounted immovably in the motor casing. The rotation of the plane defined by the commutating coils is chosen in such a manner that good commutation is assured in one of the two directions of rotation at full motor output. Furthermore, the switch (8) for reversing the direction of rotation yields the preferred direction of rotation in a first switch position and the opposite direction in a second switch position. In the switch position for the preferred direction, a smaller number of turns of the field winding (1, 2) in the electric circuit of the motor is effectively provided while, in the opposite direction of rotation of the motor, a larger number of turns is effectively provided.

Abstract: A rotor of an electric motor for a compressor which can prevent the generation of an eddy current, reduce the flux leakage between adjacent magnetic poles, thereby enhancing the operation efficiency of the motor and reducing the size of the compressor. A first end surface member formed from a nonmagnetic material, a second end surface member formed from a nonmagnetic member and a rotor core are integrally caulked by a caulking member. The rotor core is provided with a gap for preventing the short circuit of the magnetic flux caused between adjacent magnetic poles. The gap communicates with a through hole into which the caulking member is inserted.

Abstract: A motor terminal device comprises a storage case having an engaging section and installed on the motor side and a storage cover having an engaged section which can be engaged with the engaging section. The storage case stores external connecting terminals and electrical components, while the storage cover has a projecting pressers located in a position corresponding to the electrical components to secure the electrical components by pressing. The external connecting terminals have a latch hole and the storage case has a latch projection. Detachment of external connecting terminals is prevented as the latch projection is engaged with the latch hole.