Abstract: A motor capable of increasing cogging torque is provided. A motor includes a shaft; a magnetic member including a core including an annular portion and a plurality of spokes and a coil; and a magnet, wherein one of the magnetic member and the magnet is disposed at an inner side of the other; an end portion of each of the spokes and the magnet oppose one another in radial directions nm; the core includes a pair of magnetic pole portions at the end portion of each of the spokes, the a pair of magnetic pole portions extending in both directions of circumferential directions xy; and of the pair of magnetic pole portions of at least one spoke from among the plurality of spokes, the magnetic pole portion at an x side has a larger magnetic resistance than the magnetic pole portion at a y side.

Abstract: A driving apparatus according to an embodiment includes an arm, an operation target, and a brake unit. The arm has one end supported by a support mechanism, and includes an electric driving source. The operation target is attached to the other end of the arm, the other end being an end on the opposite side of the one end, and is enabled to be pivoted by the driving source about one rotational axis intersecting with a direction from the one end to the other end. The brake unit secures immobility of a target gear that is a gear disposed in the arm, and that is a gear being rotated as the operation target is pivoted, when the power supply to the driving source stops.

Abstract: A PMDC motor includes a housing, a stator magnet fixed to the inner circumferential surface of the housing, a rotor core received in the housing and facing the stator magnet, and rotor windings wound around the rotor core. The rotor core includes a plurality of rotor teeth, each of the rotor teeth including a tooth body and a tooth tip. A ratio of the outer diameter of the rotor core to an outer diameter of the housing is in the range of 0.6 to 0.67. Compared to the existing PMDC motor, the PMDC motor of the present invention can satisfy the same performance requirement, while reducing the size and weight of the rotor core and hence the weight of the rotor windings. In this way, the total weight and hence the moment of inertia of the rotor is reduced, thereby effectively reducing the noise generated during operation of the motor.

Abstract: A permanent magnet motor has a stator and a rotor rotatably mounted to the stator. The stator has a housing with n side portions and n connecting portions distributed alternately, wherein n is a integer equal to or greater than 3. Adjacent side portions are interconnected by one of the connecting portions. The radial cross section of each side portion is a convex curved line which is curved outwardly relative to a straight line passing through the two ends of the convex curve line. Permanent magnets are fixed to an inner surface of the housing. An end cap fixed to one end of the housing, has a bottom and n side walls extending from the bottom. A flat mounting surface is formed at the outer surface of a first one of the side walls.

Abstract: A DC motor comprises: a tubular metal case; a magnet that is provided along the inner surface of the metal case and has four or more of magnet poles in the circumferential direction; an armature that is arranged to face the magnet and composed of a core and a coil; and a shaft. The magnet is formed of a material with a maximum energy product BHmax of 3 to 6 MGOe. When the thickness of the magnet in the radial direction of the armature is indicated by T [mm] and the outer diameter of the core is indicated by d [mm], the ratio T/d of the thickness T of the magnet to the outer diameter d of the core is 0.16 or more.

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 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 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 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 DC motor comprises: a tubular metal case; a magnet that is provided along the inner surface of the metal case and has four or more of magnet poles in the circumferential direction; an armature that is arranged to face the magnet and composed of a core and a coil; and a shaft. The magnet is formed of a material with a maximum energy product BHmax of 3 to 6 MGOe. When the thickness of the magnet in the radial direction of the armature is indicated by T [mm] and the outer diameter of the core is indicated by d [mm], the ratio T/d of the thickness T of the magnet to the outer diameter d of the core is 0.16 or more.

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 flux-switching magnetic machine is provided having a drive element and a driven element. The drive element is configured to generate a composite magnetic field comprising a fixed component and a variable component, the fixed component being generated by spaced fixed field members and the variable component being generated by spaced armature windings. The driven element has a plurality of magnetisable portions configured to be coupled to the composite magnetic field generated by the drive element, such that the driven element moves in response to changes in this field. The number of fixed field members is greater than the number of armature windings.

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: 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 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 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: 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 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: The invention relates to a device (10) for accommodating an electric motor (30), particularly a blower motor for a heating or air-conditioning system, comprising an essentially pot-shaped accommodating housing (12) serving as a motor housing and having an accommodating opening (32) in which the pole casing (46) of an electric motor (30) can be inserted while at least partially projecting inside. The inventive device also comprises a retaining flange (14) mounted on the accommodating housing (12) and serving to fasten the motor housing (12) to a supporting element, and comprises a control and regulating unit (20) mounted on the retaining flange (14) and serving to operate the electric motor (30). The invention provides that the accommodating housing (12) has, in the peripheral direction, at least one flattened area (36,40), which differs from a circular shape while corresponds with at least one flattening (54) of an outer contour of the control and regulating unit (20).

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 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: 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: 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 has a stator having plural permanent magnets 1a and 1b; a rotor having a rotor core 3 which plural salient poles 3a and 3b are formed at, and one or more rotor coils 5 are wound around; an electromagnetic torque generating portion A comprising the stator and the rotor which, by supplying an electric current to the rotor coils 5, generates an electromagnetic torque which displaces a relative angle position of the rotor and the stator in approximate proportion to the magnitude of the electric current; and a coil spring 36 biased in approximate proportion to the magnitude of the relative angle displacement of the rotor and the stator, and thereby generating a torque in the direction opposite to the direction of the electromagnetic torque.

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: 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: The challenge to be solved by the present invention is the miniaturization of a 1-300 W class of motor. This can be achieved by using a hollow-cylinder shaped anisotropic bonded magnet magnetized in a 4-pole configuration. The anisotropic bonded magnet has a maximum energy product approximately 4 times greater than the conventional sintered ferrite magnets. The use of a 4-pole configuration shortens the magnetic path length of the individual magnetic circuits and the magnetic force contributing to the torque is increased. When the torque is kept the same as in the conventional motor, the length of the electromagnetic rotor core and the axial magnet length can be reduced. In this fashion, 1-300 W class motors can be reduced in size.

Abstract: Permanent magnet machines including doubly salient machines having one or more permanent magnets located at least partly and preferably entirely within the stator teeth, thereby avoiding weakening of the stator structure while reducing acoustic noise. The magnets may be located in only a subset of the stator teeth, thereby lowering magnet material and manufacturing costs, and all such magnets may have north poles directed toward an interior of the machine, resulting in reduced cogging and negative torques with improved torque densities. The permanent magnets may also extend within the stator teeth on an angle or diagonal, thereby allowing use of magnets which are wider than the teeth themselves to produce greater flux. Further, a magnetizing device having a single coil may be used to simultaneously magnetize all the stator magnets with a common polarity.

Abstract: A flux ring for a motor of a power tool has an annular housing which fits inside the motor can of the motor. At least one magnet is on the ring. The at least one magnet includes a portion formed from an isotropic magnetic material and a portion formed from an anisotropic magnetic material. Preferably, the isotropic magnetic material is sandwiched by the anisotropic magnetic material. The magnets being molded onto the flux ring in a two shot process.

Abstract: Embodiments of the present invention are directed to gear transmission apparatus that are configured to largely eliminate the cogging effects and to reduce the backlash effects. In one embodiment, a transmission apparatus comprises a follower gear, a first drive gear set coupled with the follower gear to drive the follower gear, and a second drive gear set coupled with the follower gear to drive the follower gear. The first drive gear set includes at least one gear, and the second drive gear set includes at least one gear. A first motor is coupled with the first drive gear set. The first motor includes a first rotor having a plurality of poles which are movably disposed relative to a plurality of magnets. A second motor is coupled with the second drive gear set. The second motor includes a second rotor having a plurality of poles which are movably disposed relative to a plurality of magnets.

Abstract: Permanent magnet machines including doubly salient machines having one or more permanent magnets located at least partly and preferably entirely within the stator teeth, thereby avoiding weakening of the stator structure while reducing acoustic noise. The magnets may be located in only a subset of the stator teeth, thereby lowering magnet material and manufacturing costs, and all such magnets may have north poles directed toward an interior of the machine, resulting in reduced cogging and negative torques with improved torque densities. The permanent magnets may also extend within the stator teeth on an angle or diagonal, thereby allowing use of magnets which are wider than the teeth themselves to produce greater flux. Further, a magnetizing device having a single coil may be used to simultaneously magnetize all the stator magnets with a common polarity.

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 DC motor which is small in size and capable of effecting a higher output, and in which magnet size is determined through a parameter by which the peak output characteristic corresponding to the shape and size of the yoke can be recognized properly.

Abstract: A flux ring for a motor of a power tool has an annular housing which fits inside the motor can of the motor. At least one magnet is on the ring. The at least one magnet includes a portion formed from an isotropic magnetic material and a portion formed from an anisotropic magnetic material. Preferably, the isotropic magnetic material is sandwiched by the anisotropic magnetic material. The magnets being molded onto the flux ring in a two shot process.

Abstract: A DC motor which is small in size and capable of effecting a higher output, and in which magnet size is determined through a parameter by which the peak output characteristic corresponding to the shape and size of the yoke can be recognized properly.