Abstract: An induction motor having a reverse-rotation preventing function, comprises: a stator provided with a winding coil generating flux by a current; an induction rotor provided with a cage and rotatably inserted in the stator, wherein a rotary shaft is coupled to its inside; a synchronous rotor provided with a permanent magnet and rotatably coupled between the stator and the induction rotor; an induction-force generating unit generating a force for moving the synchronous rotor in an axial direction; and a rotation preventing unit preventing a reverse rotation by fixing the synchronous rotor moved by the induction-force generating unit at the time of reverse rotation of the synchronous rotor.

Abstract: A permanent magnet synchronous motor includes a rotor having cage windings and permanent magnets placed on an inner peripheral side of these cage winding bars, where the permanent magnets are placed and polarized so that a ratio ?/? between a circumferential pitch angle ? of magnetic flux distribution of the permanent magnets and a magnet pole pitch angle ? is between 0.67 and 0.91.

Abstract: An apparatus for driving a compressor comprises a compressor having a compression mechanism part for sucking a fluid to compress the same, and an electric motor for driving the compression mechanism part, and an inverter device for driving the electric motor at variable speeds. The electric motor comprises a self-starting type electric motor having a rotor, which comprises a cage conductor and a polarized permanent magnet, and the inverter device comprises a plurality of semiconductor switches for controlling drive frequencies of the electric motor.

Abstract: A self-starting permanent magnet synchronous motor which demonstrates satisfactory acceleration performance even at a reduced supply voltage or with an increased load torque, and a compressor using the same. The motor comprises a stator having a stator winding and a rotor having a cage winding and a permanent magnet on the rotor core. The torque component generated by the cage winding is maximal at 1 in the slip range of 0 to 1.

Abstract: A process for mounting magnets in an electric motor rotor and an electric motor rotor, said rotor comprising: a lamination stack (10) provided with a plurality of axial channels (12) disposed around a central axial bore (11) and housing permanent magnets (20); and a rotor cage (30) formed by a pair of end rings (31), each seated against an adjacent end lamination of the lamination stack (10) and interconnected by a plurality of bars (32), said process comprising the steps of: forming an end, ring (31) with at least one inner radial projection (33) disposed radially external to the projection of the contour of an axial channel (12); mounting in each axial channel (12) at least one permanent magnet (20); and deforming each inner radial projection (33) in order to increase its radial extension the sufficient to radially cover at least part of the projection of the contour of said axial channel (12), defining a stop for axially retaining the respective permanent magnet (20).

Abstract: A system for transferring torque between a pair of independently, concurrently rotating shafts of a turbofan engine includes a magnetic gearbox. The magnetic gearbox has a first ring structure, a second ring structure and an intermediate ring structure. Each ring structure has an annular aperture therethrough and a plurality of permanent magnets embedded therein. The intermediate ring structure is disposed between the first and the second ring structures. Each ring structure is coaxially concentric with, and independently rotatable with respect to the remaining ring structures. The first and second ring structures are each coupled to separate ones of the rotating engine shafts, and the intermediate ring is operable to transfer torque between the pair of shafts. Preferably, the intermediate ring structure is coupled to a rotating machine. The rotating machine has a controller, and is operable for adjusting a ratio of torque transferred between the pair of shafts.

Abstract: A synchronous motor includes a stator, a rotor and permanent magnets. The rotor includes a rotor iron core that is rotatable relative to the stator, and conductor bars accommodated within corresponding slots in the rotor iron core. The conductor bars have their opposite ends short-circuited by respective shortcircuit rings to form a starter cage conductor. The rotor also has a plurality of magnet retaining holes defined therein, in which permanent magnets are embedded. The conductor bar holes are positioned in an axial direction and inwardly from the magnet retaining holes. The conductor bars within the holes protrude outwardly from an axial end of the rotor iron core to form projections for securing an end plate to the end of the rotor iron core, the end plate comprising a non-magnetizable material.

Abstract: The invention provides a rotor for an electrical motor, a tool for making a rotor core and a method of making the rotor. The rotor could be incorporated e.g. in a line-start motor and comprises a squirrel cage and magnet located in a rotor core. The magnets are, in one end of the rotor, secured by an end plate with apertures which are larger than the magnet openings, and the end plate is indexed relative to the magnet slots such that a first portion of openings into the magnet slots is in communication with the aperture and such that a remaining, second, portion of the magnet slots is covered by the end plate. In one aspect, the end plate forms an integrated part of the rotor core and comprises openings cooperating with conductor slots to form through-going passages for conductors of the squirrel cage. In that way, the end plate is held in a completely fixed position by the squirrel cage which is moulded directly onto the core and into the conductor slots.

Abstract: The invention relates to a rotor for an electric motor, especially an electric line-start motor, comprising spaces (4 to 7) which receive permanent magnets (10 to 13) and extend in an axial direction, and spaces (20 to 25) that accommodate conductor rods and extend in an axial direction. In order for the rotor to run as regularly as possible, the spaces (20 to 25) accommodating the conductor rods are provided with a substantially elongate cross-section in at least one sector of the rotor while being embodied in a curved manner along the longitudinal axis thereof in said sector when viewed from a cross-sectional perspective.

Abstract: The invention relates to a rotor for an electric motor, particularly an electric line-start motor, comprising axially accommodating spaces (4 to 6) for conductor rods, and axially extending receiving spaces (10, 11) for permanent magnets (14, 15), which are-designed and located in such a way that they generate a permanent magnet field with a magnet axis (22) and a neutral axis (23). The aim of the invention is to ensure that the rotor runs as regularly as possible during the operation of the electric motor. To this end, the diameter of the rotor along the magnet axis is larger than that along the neutral axis (23).

Abstract: A synchronous motor includes a stator, a rotor and permanent magnets. The rotor includes a rotor iron core that is rotatable relative to the stator, and a plurality of conductor bars accommodated within corresponding slots in the rotor iron core. The conductor bars have their opposite ends shortcircuited by respective shortcircuit rings to form a starter cage conductor. The rotor also has a plurality of magnet retaining slots defined therein at a location on an inner side of the conductor bars, in which hole permanent magnets are embedded.

Abstract: There are problems in a rotor having a slit that it is difficult to increase the number of rotations of the rotor, since the centrifugal force is received at both ends of the slit, and if the connection part is made thick to increase the number of rotations, the properties of the motor is deteriorated. According to the present invention, a rotor for a synchronous motor includes a slot for generating induction torque and a slit for generating reluctance torque, the slit is filled with a filler, the slit is provided with at least one of a convex and a concave, so that the convex and the concave are formed so as to receive the centrifugal force which is generated by the rotation of the rotor and acts on a part of the rotor outside the slit and the filler so as to bulge toward the outside from the center side of the rotor by mechanical bondage of the filler and the rotor core.

Abstract: A synchronous motor includes a stator, a rotor and permanent magnets. The rotor includes a rotor iron core rotatable relative to the stator, and a plurality of conductor bars accommodated within corresponding slots in the rotor iron core. The conductor bars have their opposite ends shortcircuited by respective shortcircuit rings to form a starter cage conductor. The rotor also has a plurality of magnet retaining slots defined therein at a location on an inner side of the conductor bars, in which hole permanent magnets are embedded.

Abstract: The novel squirrel-cage rotor should enable a power output of the motor of more than 1 MW even at rotation speeds of more than 10,000 rpm. To this end, the conductor bars (4) of the squirrel cage are soldered into slots (8, 9) arranged on the periphery of the massive rotor core (3) across their entire length, and the conductor bars are arranged to be flush with the surface (13) of the rotor core (3).

Abstract: A rotor of an induction starting synchronous motor includes permanent magnets and induction coils having both ends short-circuited in a core. The permanent magnets are arranged side by side in a longitudinal direction of the core to form a plurality of sets of permanent magnets. Two sets of the permanent magnets form respective poles of the induction starting synchronous motor. The two sets of permanent magnets forming each of the poles are located inclined or slightly shifted in a cross-sectional plane of the core by rotating the two sets of permanent magnets about corners of the permanent magnets nearest the induction coils as rotating axes into directions such that magnetic fluxes induced by the two sets of permanent magnets are cancelled each other. With this construction, the induction starting synchronous motor can be smoothly started and operated with improved power factor and efficiency characteristics.

Abstract: A synchronous motor includes a stator, a rotor and permanent magnets. The rotor includes a rotor iron core and rotatable relative to the stator, a plurality of conductor bars accommodated within corresponding slots in the rotor iron core. The conductor bars have their opposite ends shortcircuited by respective shortcircuit rings to form a starter cage conductor. The rotor also has a plurality of magnet retaining slots defined therein at a location on an inner side of the conductor bars, in which hole permanent magnets are embedded.

Abstract: An embedded permanent magnet type induction motor has a rotor that is a lamination of a plurality of rotor core plates (10). The rotor core plate is provided with a plurality of rotor slots (12) each inclined by an angle &agr; with respect to a radial direction of the rotor core plate. The rotor has the axial length L being made of laminations divided into at least two equal portions with respect to its central axis. The divided laminations are combined with one another so that one of the divided laminations is opposed to another in inclination of the angle &agr; and the plurality of rotor slots of one of the divided laminations are respectively superposed on the rotor slots of another at at least their ends closer to the central axis of the rotor to form a skew angle &bgr;.

Abstract: A single phase line start permanent magnet synchronous motor is started by an interaction between magnetic fields of the coil and of the secondary conductor, and an normal operation can be performed using only the permanent magnet and the operating condenser of small capacity, only the main coil, or only the operating condenser when the synchronous rotating speed is reached and the rotation is started, and therefore an additional direct current supplying device for supplying the direct current and the position sensor for sensing the rotational position of the rotor can be excluded, the structure can be made compactly by constructing the driving circuit simply, and manufacturing cost can be reduced.

Abstract: A rotor of an induction starting synchronous motor includes permanent magnets and induction coils having both ends short-circuited in a core. The permanent magnets are arranged side by side in a longitudinal direction of the core to form a plurality of sets of permanent magnets. Two sets of the permanent magnets form respective poles of the induction starting synchronous motor. The two sets of permanent magnets forming each of the poles are located inclined or slightly shifted in a cross-sectional plane of the core by rotating the two sets of permanent magnets about corners of the permanent magnets nearest the induction coils as rotating axes into directions such that magnetic fluxes induced by the two sets of permanent magnets are cancelled each other. With this construction, the induction starting synchronous motor can be smoothly started and operated with improved power factor and efficiency characteristics.

Abstract: A synchronous induction motor realizing a great reluctance torque by concentrating a magnetomotive force generated by a rotor provided with a permanent magnet having a two-pole structure, and having a high efficiency. The synchronous induction motor has a stator provided with a stator winding, a rotor rotating within the stator, a cage-type secondary electric conductor provided in a peripheral portion of a rotor yoke portion constituting the rotor, and a permanent magnet inserted into the rotor yoke portion and having a two-pole structure, and the magnetomotive force generated by one pole of the rotor is set to a value equal to or less than 10% of a peak value in a predetermined range near an electrical angle of 0 degrees or 180 degrees.

Abstract: A reluctance type rotating machine includes a stator 1 having armature windings 2 arranged on an inner periphery of the stator 1, a rotor 3 having a magnetic unevenness in the circumferential direction and a plurality of permanent magnets 6 arranged for negating the armature windings' flux passing between adjoining poles. Each magnet 6 is magnetized in a direction different from a direction to facilitate the rotor's magnetization. A magnetic portion 7 is provided between the pole and the interpole of the rotor 3. Owing to the provision of the magnetic portion 7, when the armature windings are not excited, more than 30% of the permanent magnets' flux is distributed in the rotor 3. Similarly, when the machine is loaded, the permanent magnets' interlinkage flux is more than 10% of composite interlinkage flux composed of armature current and the permanent magnets.

Abstract: An embedded permanent magnet type induction motor has a rotor that is a lamination of a plurality of rotor core plates (10). The rotor core plate is provided with a plurality of rotor slots (12) each inclined by an angle &agr; with respect to a radial direction of the rotor core plate. The rotor has the axial length L being made of laminations divided into at least two equal portions with respect to its central axis. The divided laminations are combined with one another so that one of the divided laminations is opposed to another in inclination of the angle &agr; and the plurality of rotor slots of one of the divided laminations are respectively superposed on the rotor slots of another at at least their ends closer to the central axis of the rotor to form a skew angle &bgr;.

Abstract: A rotor is provided for a permanent magnet type rotating machine having a stator 1 with armature windings 11. The rotor 3 includes a rotor core 31 and a plurality of permanent magnets 32 arranged in the rotor core 31 so as to negate magnetic flux of the armature windings 11 passing through interpoles 3b. The rotor 3 is constructed so that the average of magnetic flux in an air gap 2 between the rotor 3 and the stator 1, which is produced by the permanent magnets 32 at the armature windings' de-energized, ranges from 0.1 [T] to 0.7 [T] and the ratio (Lq/Ld) of self-inductance of the magnetic portion in a hard-magnetizing direction (q-axis) to self-inductance in an easy-magnetizing direction (d-axis) under a rated load condition ranges from 0.1 to 0.8. Under these conditions, it is possible to realize the rotating machine which operates as an induction machine at the machine's starting and also operates as an synchronous machine at the rated driving due to smooth pull-in.