Abstract: A small DC motor includes a motor frame having a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that comprises four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle comprising the four sides; and a magnet having a circumferential surface on an inside thereof and having conformable contact with the motor frame on an outside thereof.

Abstract: A magnetic drive enhancement is provided to offset kinetic forces found in a rotational system to improve the mechanical efficiency of the rotational system. A housing includes rotationally biased magnetic fields in which a central axle or driveshaft may rotate. The magnetic fields are generated, shaped, and rotationally biased by a plurality of driving magnets and magnetic shields. Attached to the driveshaft are magnetic receivers, which are influenced by the rotationally biased magnetic fields at varying strengths as they orbit within the housing. The magnetic fields are shaped to provide increasing and decreasing strength of flux to counteract the physical forces experienced by the driveshaft to thereby increase the efficiency of the rotational system.

Abstract: A small DC motor includes a motor frame having a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that comprises four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle comprising the four sides; and a magnet having a circumferential surface on an inside thereof and having conformable contact with the motor frame on an outside thereof.

Abstract: An electric motor includes a yoke having a cylindrical section, two pairs of permanent magnets disposed at an inner circumferential surface of the cylindrical section to oppose each other, and an armature rotatably supported further inside in a radial direction than the permanent magnets, wherein at least a pair of first flat sections opposing each other in the radial direction are formed at the cylindrical section, and the permanent magnets are disposed at positions distant from the first flat sections.

Abstract: A fault current limiter (FCL) includes at least one magnetisable core member and at least one AC magnetomotive force source configured to generate a varying magnetic flux in at least a portion of the at least one magnetisable core member. At least one static magnetomotive force source is positioned to provide a magnetic circuit within at least part of the at least one magnetisable core member and the AC magnetomotive force source and the static magnetomotive force source are relatively positioned to be orthogonal to each other. Typically the static magnetomotive force source may be a permanent magnet and the AC magnetomotive force source configured to generate a varying magnetic flux in both of first and second spaced core members.

Abstract: A transmission unit of a motor vehicle, with a transmission having a transmission shaft and with an electric motor that is coupled thereto in an axial direction and that has a stator and that has a rotor arranged on a motor shaft and that is bearingless on the A-side. The electric motor includes an end plate on the B-side, and the stator is located at least partly inside a housing of the transmission.

Abstract: An asymmetric brushless direct current (DC) motor having a stator having a plurality of magnets and a rotor having a plurality of armatures where the vector sum of magnetic forces between each armature and each respective magnet is zero at every angular rotation position of the rotor with respect to the stator in the motor's non-energized state.

Abstract: An electric motor has a rotor and a stator. The rotor or the stator has arced permanent magnets that have essentially the same inner radius (IR) and outer radius (OR). In an aspect, the stator has a stator housing having a plurality of poles. Each pole includes a plurality of flat magnets affixed to an inner surface of the stator housing. In an aspect, flats on the outside of the stator housing key the stator assembly in a power tool housing. In an aspect, flat magnets are pre-magnetized, pre-assembled with alternating magnetic polarities, inserted into a stator housing, and remagnetized to a final, desired magnetic polarity configuration. In an aspect, pre-magnetized magnets and unmagnetized magnets are pre-assembled with unmagnetized magnets between magnetized magnets, the pre-assembled magnets inserted into a stator housing, and the unmagnetized magnets magnetized to a final, desired magnetic polarity configuration.

Abstract: A method for preparing the magnet includes the steps of: (a) providing a sintered Nd base magnet block having surfaces and a magnetization direction, (b) coating the surfaces of the magnet block excluding the surface perpendicular to the magnetization direction with a Dy or Tb oxide powder, a Dy or Tb fluoride powder, or a Dy or Tb-containing alloy powder, (c) treating the coated block at a high temperature for causing Dy or Tb to diffuse into the block, and (d) cutting the block in a plane perpendicular to the magnetization direction into a magnet segment having a coercive force distribution on the cut section that the coercive force is high at the periphery and lower toward the inside and a constant coercive force distribution in the magnetization direction.

Abstract: An electric motor includes at least one first brush and at least one second brush, which are arranged in a stationary fashion and arranged to contact a commutator that rotates with a rotor. The commutator includes at least one cylindrical section with a circumferential surface on which a plurality of segments are arranged with insulating sections interposed between them. In order to detect the rotating speed and position of the rotor, the motor includes brushes with asymmetric circumferential widths or angles or a stator with an uneven magnetization. The motor is arranged to detect only one signal when the rotor rotates for an angle between two adjacent segments.

Abstract: A small DC motor includes a motor frame having a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that comprises four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle comprising the four sides; and a magnet having a circumferential surface on an inside thereof and having conformable contact with the motor frame on an outside thereof.

Abstract: A flux-focused, shaped permanent magnet includes a body of magnetic material having multiple surface contouring to form a reduced flux side with convex surfaces and an increased flux side with concave surfaces. The surfaces develop high and low resistance external flux paths creating focused asymmetric flux fields. A magnetic unit having the shaped permanent magnet and a magnetic flux attracter or two shaped permanent magnets interconnected by two segmented permanent magnets and a kinetic device having a stationary stator ring, a rotor disc rotating within the stator ring and a multiplicity of the magnetic units on the stator ring and the rotor disc, are also provided.

Abstract: A window lift has a motor and a gearbox. The motor is a permanent magnet motor, comprising a stator and a rotor rotatably mounted to the stator. The stator or the rotor comprises a housing and magnets fixed to inner surface of the housing. The radial cross section of the housing comprises n side portions and n connecting portions, where n is an integer greater than 2. Adjacent side portions are connected together by one corresponding connecting portion and the magnets are fixed at portions corresponding to the connecting portions. The radial cross section of each side portion is like a convex curve line, which is curved outwardly relative to a straight line passing through the two ends of the convex curve line.

Abstract: An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

Abstract: An electrical machine including a permanent magnet and a coil is provided. The coil is arranged to interact with the permanent magnet via an air gap, which located between the two. Electrical power is generated in the coil when the permanent magnet or the coil is moved in their relative position to each other. The permanent magnet includes a surface, which is aligned to the coil and to the air gap so that that magnetic forces of the permanent magnet interact via the surface and the air gap with the coil by a magnetic flux density distribution. The permanent magnet also includes a base plane and a transition area. A first side of the surface is connected with the adjacent base plane via the transition area. The cross-section of the transition between the surface and the adjacent base plane is determined by a Bezier function.

Abstract: A small DC motor includes a motor frame having a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that comprises four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle comprising the four sides; and a magnet having a circumferential surface on an inside thereof and having conformable contact with the motor frame on an outside thereof.

Abstract: A rotary actuator includes a multi-polar magnet, in which north and south poles are alternately arranged in a circumferential direction, the multi-polar magnet being shaped into one of a circular ring and a circular arc member; and a coil body having coils which are provided around the multi-polar magnet to be capable of moving in the circumferential direction of the multi-polar magnet, each of the coils substantially lying on a plane that extends in a radial direction of the multi-polar magnet and orthogonal to the circumferential direction of the multi-polar magnet. The north and south poles of the multi-polar magnet are positioned apart from each other by a predetermined interval in the circumferential direction. Dimensions of each coil are predetermined so that length of each coil in the circumferential direction is associated with the predetermined interval. Predetermined currents are passed through the coils in a properly phased manner.

Abstract: A motor comprises a stator and a rotor (20) disposed within the stator. The stator comprises: a housing (31) having a polygon cross section that comprises a plurality of side portions (32a-32d) and a plurality of curved corner portions (33a-33d), each of the corner portions connect two adjacent side portions and curve around a center (O?) which is offset from the rotational center (O) of the rotor; and a ring magnet (34) fixed to the inner surface of the housing. An air gap (37) is formed between a peripheral surface of the rotor (35) and an inner surface of the ring magnet (34). The thickness of the ring magnet at portions corresponding to the corner portions (33a-33d) of the housing being larger than the thickness of the ring magnet at portions corresponding to the side portions (32a-32d) of the housing.

Abstract: The side wall of a motor casing is formed into a quadrangular shape such that four flat side portions, and arcuate corner portions located at respective corners are continuously joined together. A field magnet having a quadrangular external shape is formed such that four flat side portions, and four arcuate corner portions located at respective corners are continuously joined together. The arcuate corner portions of the motor casing and the arcuate corner portions of the field magnet extend along respective circles having a center located at the center of a motor shaft, and the central angles of the arcuate corner portions fall within a range of 15° to 35° inclusive. The field magnet is press-fitted or bonded into the motor casing such that the corner portions of the field magnet come into close contact with the corner portions of the motor casing.

Abstract: A motor comprises a stator and a rotor (20) disposed within the stator. The stator comprises a shell comprising a plurality of sidewalls (10a-10d) and arcuate connection parts (11a-11d) connecting neighboring sidewalls. The cross section of the shell is a polygon with fillets. The stator also comprises a plurality of magnets (12a-12d) installed inside the arcuate connection parts. The magnets (12a-12d) are mutual arranged at intervals. The outer surface of each magnet (12a-12d) is attached to inner surfaces of the two neighboring sidewalls (10a-10b) and a gap is formed between the magnet and the inner surface of the corresponding arcuate connection part. Air gaps are formed between the inner surface of the magnets (12a-12d) and the outer surface of the rotor. Disposing the magnets inside the arcuate connection parts improves the space utilization ratio.

Abstract: An electric motor has a rotor (20), a housing (10) and a ring magnet (12) fixed onto an inner surface of the housing. The housing (10) has a cross section in a polygon, preferably tetragonal, shape that comprises a plurality of side portions (10a˜10d) and a plurality of curved corner portions (11a˜11d), each of which connects two adjacent side portions. The thickness of the ring magnet at portions corresponding to the corner portions of the housing is larger than the thickness of the ring magnet at portions corresponding to the side portions of the housing. An air gap (123) is formed between a peripheral surface of the rotor and an inner surface of the ring magnet, the thickness of the air gap at portions corresponding to the corner portions of the housing being smaller than that of the air gap at portions corresponding to the side portions of the housing. The motor has a polygon housing which is convenient to install and has good space utilization.

Abstract: A small DC motor includes a motor frame having a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that comprises four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle comprising the four sides; and a magnet having a circumferential surface on an inside thereof and having conformable contact with the motor frame on an outside thereof.

Abstract: A flux-focused, shaped permanent magnet includes a body of magnetic material having multiple surface contouring to form a reduced flux side with convex surfaces and an increased flux side with concave surfaces. The surfaces develop high and low resistance external flux paths creating focused asymmetric flux fields. A magnetic unit having the shaped permanent magnet and a magnetic flux attracter or two shaped permanent magnets interconnected by two segmented permanent magnets and a kinetic device having a stationary stator ring, a rotor disc rotating within the stator ring and a multiplicity of the magnetic units on the stator ring and the rotor disc, are also provided.

Abstract: A DC motor 10 includes: a housing 12 having a polygonal cross section; a magnet 20 provided along the inner circumference of the housing 12 and having magnetic poles at the corners of the housing 12; a shaft 22 configured to be inserted into the housing 12 along the axial line of the housing 12; an armature 24 secured to the shaft 22 and provided to face the magnet 20; a commutator 26 fitted to the shaft 22 so as to be coaxial with the armature 24; a columnar carbon brush 30 provided in alignment with the radial direction of the commutator 26 such the end surface of the brush is in sliding contact with the outer circumference of the commutator 26; and a biasing member provided in the housing 12 and configured to bias the carbon brush 30 toward the commutator 26. The carbon brush 30 is provided at a position along the circumference of the housing 12 where the maximum length of the carbon brush 30 is ensured.

Abstract: A permanent magnet machine includes a stator having a hollow core, a rotor rotatably disposed inside the hollow core, and a plurality of multilayered permanent magnets embedded in the rotor. Each multilayered permanent magnet has opposite first and second ends, and includes a first magnet disposed at the first end, and a second magnet disposed at the second end and coupled to the first magnet. The second magnet has higher magnet strength than the first magnet, and also has lower high-temperature stability than the first magnet.

Abstract: A rotating electromagnetic machine has a tubular axle with mounting rings, a common ring, a coil input ring, and at least one bearing set mounted on it. A fitting is secured at a distal end of the tubular axle, and a commutator is secured at the proximal end. A housing is mounted on the bearing sets through adaptors. Connecting bars extend axially within the axle with lateral rods joined to the connecting bars at their distal ends, the bars commuting between segments of the commutator electromagnetic coils. A plurality of the electromagnetic coils are secured to the coil input ring. The coils are formed of spiral turns of a single flat strip electrically conductive material. A plurality of peripheral and sector magnets are mounted adjacent to the electromagnetic coils with electromagnetic interaction when relative motion occurs between the coils and the magnets.

Abstract: A linear actuating device contains a top magnet and a bottom magnet. The bottom magnet is axially aligned with the top magnet. The top magnet and the bottom magnet have opposing magnetization. A washer is sandwiched between the top magnet and the bottom magnet. A top coil is positioned within the top magnet. A bottom coil is positioned within the bottom magnet. A slug is slidably positioned within the top coil and bottom coil. An actuating member is integral with the slug.

Abstract: A window lift has a motor and a gearbox. The motor is a permanent magnet motor, comprising a stator and a rotor rotatably mounted to the stator. The stator or the rotor comprises a housing and magnets fixed to inner surface of the housing. The radial cross section of the housing comprises n side portions and n connecting portions, where n is an integer greater than 2. Adjacent side portions are connected together by one corresponding connecting portion and the magnets are fixed at portions corresponding to the connecting portions. The radial cross section of each side portion is like a convex curve line, which is curved outwardly relative to a straight line passing through the two ends of the convex curve line.

Abstract: An electromechanical device or magnetic motor includes a plurality of rotor magnet assemblies, a plurality of drive magnet assemblies that are laterally moveable with respect to the rotor magnet assemblies, a timing assembly for generating power pulses selectively supplied to the drive magnet assemblies, and electromagnetic coils associated with the drive magnet assemblies to receive the power pulses from the timing assembly to momentarily disrupt the magnetic field of such assemblies at selected times. The magnetic assemblies of the rotor mechanically rotate a shaft and interact with alternator windings to generate electrical power. The magnetic motor is self-contained with start/stop, rotational speed, diagnostics, global positioning, CPU and interface capability.

Abstract: A small DC motor includes a motor frame having a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that comprises four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle comprising the four sides; and a magnet having a circumferential surface on an inside thereof and having conformable contact with the motor frame on an outside thereof.

Abstract: A brush type motor including a stator having at least one magnet with an inner circumferential surface is provided. The inner circumferential surface is defined by a first radius orthogonally extending from a first axially extending centerline. The motor has an armature disposed within an interior region of the stator having teeth. Each tooth has an arcuate surface defined by a second radius orthogonally extending from a second axially extending centerline. At least one tooth is radially closer to the inner circumferential surface than the teeth adjacent to the at least one tooth. Each tooth further includes at least one dummy notch extending into the tooth. The first axially extending centerline is in a first position different than a second position of the second axially extending centerline.

Abstract: A small-sized motor includes a field magnet attached to an inner circumferential surface of a metallic motor casing and having four or more magnetic poles. The field magnet is formed of a single ring-shaped magnet member having a predetermined thickness with respect to the radial direction and a predetermined length with respect to the thrust direction. At each of portions between the magnetic poles formed through magnetization, the magnet member has a thin portion having a reduced thickness with respect to the radial direction, the thin portion being formed by cutting the magnet member from the radially outward side. The magnetization is performed in the radial direction so as to alternately form S poles and N poles in the circumferential direction. At each of portions between the magnetic poles, the magnet member may have cut portions formed at opposite end portions of the magnet member with respect to the thrust direction.

Abstract: A small DC motor includes a motor frame having a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that comprises four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle comprising the four sides; and a magnet having a circumferential surface on an inside thereof and having conformable contact with the motor frame on an outside thereof.

Abstract: A small DC motor includes: a motor frame including a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that includes four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle including the four sides; field magnets; and an armature assembly, wherein the field magnets are provided so as to be spaced apart from each other, and the small DC motor includes an air gap between each of the four sides and a radially outermost surface of the armature assembly, the air gap being a minimum size needed to rotate the armature assembly.

Abstract: An electric motor has a rotor and a stator. The rotor or the stator has arced permanent magnets that have essentially the same inner radius (IR) and outer radius (OR). In an aspect, the stator has a stator housing having a plurality of poles. Each pole includes a plurality of flat magnets affixed to an inner surface of the stator housing. In an aspect, flats on the outside of the stator housing key the stator assembly in a power tool housing. In an aspect, flat magnets are pre-magnetized, pre-assembled with alternating magnetic polarities, inserted into a stator housing, and remagnetized to a final, desired magnetic polarity configuration. In an aspect, pre-magnetized magnets and unmagnetized magnets are pre-assembled with unmagnetized magnets between magnetized magnets, the pre-assembled magnets inserted into a stator housing, and the unmagnetized magnets magnetized to a final, desired magnetic polarity configuration.

Abstract: An electric motor has a housing, a rotor rotatably installed in the housing, n permanent magnets with the same polarity fixed at an inner surface of the housing. The rotor is a wound armature having a plurality of teeth extending in a radial direction. The housing includes n inner projecting parts, the permanent magnets and the inner projecting parts being alternately arranged in a circumferential direction about the rotor. The magnets generate 2n magnetic circuits via the housing and the rotor, n being an integer greater than one. The size of at least a portion of a first air gap formed between the permanent magnets and the rotor is greater than the size of at least a portion of a second air gap formed between the inner projecting parts and the rotor.

Abstract: Bonding geometries are disclosed between permanent magnets and steel portions of magnetic assemblies. When employed in permanent magnet motors, this particular bonding construction reduces or even eliminates the loosening of permanent magnets inside of electric motors. The bonding geometry consists of interlocking protrusions and voids at the bonding interface. A bonding agent is employed that may be filled with finely divided iron or other magnetic material. The result is a strong bond between the permanent magnet and steel assembly portions with virtually no loss in overall magnetic properties.

Abstract: A rotor is operable to rotate in a rotating direction, and is provided with five teeth that define five slots therebetween at regular intervals in the rotating direction. A pair of arc-shaped magnets surrounds the rotor, and faces each other through the rotor. A value of a circumferential angle between two adjacent slots with respect to an axis of the rotor is defined as a. A value of a circumferential angle between opposite end edges of an inner surface of the magnet in a circumferential direction of the magnet, which faces the rotor, with respect to the axis of the rotor is defined as b. The value of b falls within a range from 23 to 25 when the value of a is assumed as 12.

Abstract: A small DC motor includes a motor frame having a cylindrical portion, the cylindrical portion having a constant thickness and having a cross section in a shape that comprises four sides and connecting portions, each of the connecting portions connecting adjacent two of the four sides and being located inward from a corresponding corner in a quadrangle comprising the four sides; and a magnet having a circumferential surface on an inside thereof and having conformable contact with the motor frame on an outside thereof.

Abstract: An electric motor (1) has a stator (3), a rotor (2) and a number of permanent magnets (6). The use of permanent magnets (6) having a cuboidal shape, without impairing performance. The stator (3) has a number of permanent magnets (6) having a cuboidal shape, which are embedded in recesses (7) and whose axial length (8) is greater than the axial length (4) of the stator (3).

Abstract: A small-sized motor having a polygonal outer shape includes four or more field magnets attached to the inner surface of a motor casing made of metal. A tubular portion of the motor casing is formed into a polygonal tubular shape such that flat side portions equal in number to field poles, and flat or curved corner portions equal in number to the field poles and each being located between the adjacent side portions are sequentially joined together. The field magnets have a smaller thickness at portions corresponding to the side portions of the motor casing and a larger thickness at portions corresponding to the corner portions of the motor casing. The field magnets are fixed while coinciding in center position with the corresponding corner portions of the motor casing and while being pressed against the corresponding corner portions of the motor casing from inside.

Abstract: A small-sized motor having a polygonal outer shape includes four or more field magnets attached to the inner surface of a motor casing made of metal. A tubular portion of the motor casing is formed into a polygonal tubular shape such that flat side portions equal in number to field poles, and flat or curved corner portions equal in number to the field poles and each being located between the adjacent side portions are sequentially joined together. The field magnets have a smaller thickness at portions corresponding to the side portions of the motor casing and a larger thickness at portions corresponding to the corner portions of the motor casing. The field magnets are fixed while coinciding in center position with the corresponding corner portions of the motor casing and while being pressed against the corresponding corner portions of the motor casing from inside.

Abstract: Bonding geometries are disclosed between permanent magnets and steel portions of magnetic assemblies. When employed in permanent magnet motors, this particular bonding construction reduces or even eliminates the loosening of permanent magnets inside of electric motors. The bonding geometry consists of interlocking protrusions and voids at the bonding interface. A bonding agent is employed that may be filled with finely divided iron or other magnetic material. The result is a strong bond between the permanent magnet and steel assembly portions with virtually no loss in overall magnetic properties.

Abstract: A miniature PMDC motor 10 has a permanent magnet stator comprising two arcuate ceramic magnets 20 fitted to a can-like housing 11 and circumferentially separated by interdisposed rubber magnets 21 wedging or nipping the ceramic magnets 20 in place within the housing 11 without the use of circumferential magnet stops formed in the side of the housing.

Abstract: A permanent magnet field small DC motor includes an arc-shaped rare earth magnet of maximum thickness 1 mm or less fabricated by compression molding from rare earth iron based melt-spun flakes and a binder. The magnet is provided with a certain specific portion at both ends in the circumferential direction, which has no back yoke when the magnet is press-fit in a soft-magnetic frame. The arc-shaped rare earth magnet fabricated by compression molding from a material containing more rare earth iron based melt-spun flakes exhibits simultaneous increase of both a remanence as a function of magnetizing field and a coercivity; and hence, exhibits a well-balanced demagnetization curve even in an unsaturated magnetized state.

Abstract: A DC motor includes a stator of magnets surrounding a rotor containing coils of wire surrounding cores. Brushes serve to repeatedly start and interrupt the supply of current to the individual coils via respective commutator segments of the rotor in order to rotate the rotor. Each pole includes a reduced magnetic flux density area and an increased magnetic flux density area. The potential discharge between the commutator segments and the brushes supplying current to the individual coils is reduced by altering the magnetic forces of the poles within the reduced magnetic flux density area and the increased magnetic flux density area. The magnetic forces of the poles are altered by using either separate magnets of varying levels of strength or by altering the gap between the cores and the poles.

Abstract: When one of armature coils is in a beginning of a commutation process, a center line of a trailing end tooth of a corresponding group of teeth, around which the one of the armature coils is wound, is generally aligned with a corresponding boundary between magnets. When the one of the armature coils is in an end of the commutation process, a center line of a leading end tooth of the corresponding group of the teeth is generally aligned with another boundary between the magnets.

Abstract: Field magnets are attached to an inner periphery of a stator core, which defines a rotor through hole. The stator core has a plurality of recesses open to the rotor through hole. Each recess faces magnet end portions of the field magnets. The recess surface of the recess is away from the surface AC of the magnet end portion and set back toward an outer periphery of the stator core from a rear surface AD of the magnet end portion.

Abstract: A miniature PMDC motor 10 has a permanent magnet stator comprising two arcuate ceramic magnets 20 fitted to a can-like housing 11 and circumferentially separated by interdisposed rubber magnets 21 wedging or nipping the ceramic magnets 20 in place within the housing 11 without the use of circumferential magnet stops formed in the side of the housing.

Abstract: The electric motor with permanent-magnet excitation has a stator (1), a rotor (7) supported inside the stator and adjacent permanent magnets (8, 9, 10, 11) of opposite polarity arranged next to each other on a rotor surface facing the stator. The rotor (7) has cavities (16, 17, 18, 19) arranged within a rotor interior and indentations (12, 13, 14, 15) in the rotor surface, which are arranged so that radially oriented magnetic flux lines are not interrupted by the cavities and indentations, but magnetic flux lines oriented tangentially to the rotor surface are interrupted by the cavities and indentations so that a magnetic short circuit is formed. These indentations and cavities reduce the rotor heat capacity so that a layer of a magnetic material that forms the permanent magnets (8, 9, 10, 11) can be sprayed onto the rotor surface.