An ironless magnet assembly (128) for a loudspeaker (101) comprising two pairs of magnets (136) is disclosed. Each magnet (136) of each pair having a north pole and a south pole, a first pair of magnets (136c, 136d) are arranged with the north poles of the magnets of that pair facing each other and a second pair of magnets (136a, 136b) are arranged with the south poles of the magnets of that pair facing each other. The first pair of magnets (136c, 136d) are located opposite the second pair of magnets (136a, 136b) to define a voice coil gap (112) therebetween with each north pole of the first pair being located opposite a south pole of the second pair across the voice coil gap (112).

An electronic device may include a housing, a first frame disposed inside the housing and including a first surface, a second frame forming an internal space by being coupled with the first frame, and including a second surface opposed to the first surface, a speaker disposed in the internal space and including at least one voice coil, and a battery disposed on a side of the second frame. The second frame may include at least one frame hole, and a ratio μ/μ0 of a magnetic permeability to a vacuum permeability of at least one of a material of the first frame or a material of the second frame may be equal to or greater than 1000.

An electric motor including two magnetic assemblies each having an even number of magnets in a circular arrangement, the magnets arranged in a bucking configuration with like poles directed at each other. There are a plurality of ferrous members for each of the magnetic assemblies arranged between each of the magnets. The ferrous members having a face that is directed radially toward a face of another ferrous member of the corresponding magnetic assembly. An electromagnetic assembly has a plurality of electromagnetic members arranged in a generally circular arrangement and is located radially between the two magnetic assemblies. Each electromagnetic member has a ferrous element with an electrical conductor wound around the ferrous element, each ferrous element having an inward and outward face respectively being directed to the ferrous members of the two magnetic assemblies as they pass each other as the magnet assemblies rotate relative to the electromagnetic assembly.

An electric motor including a driven element, a magnet assembly and a driving element. The driven element being driven in a direction of movement. The magnet assembly is includes first and second magnets each having first and second magnetic poles. The first magnetic pole of the first magnet and the first magnetic pole of the second magnet being proximate to each other and facing each other thereby defining a first magnetic zone therebetween. The first magnetic poles all being similar, and the second magnetic poles all being similar. The driving element is proximate to the magnet assembly, producing a magnetic field within the driving element that is primarily orthogonal to the direction of movement.

The present invention discloses a loudspeaker driver comprising a magnet system having at least one gap where in each gap a voice coil assembly is arranged for movement in the gap, wherein either two distinct coils are arranged on the voice coil assembly, one above the other, and the magnet system comprises two pole pieces, one above the other, creating a pair of magnetized areas between said pole pieces and a yoke, such that a magnetic flux field is created between each pole piece and the yoke. In an alternative two concentric gaps are provided, where the voice coil assembly comprises two concentrically arranged sub-voice coils, where each sub-voice coil is provided with a distinct voice coil and the magnet assembly has two concentrically arranged magnet rings arranged with a yoke in the center, such that two concentric gaps are created, and that the voice coil assembly moves substantially orthogonal to the flux fields in the gap(s) and further that at least the part of each pole piece facing the gap(s) is made from a soft magnetic composite (SMC) material.

A yoke for the speaker includes: a parent member molded of an iron-based powder; and a heterogeneous material molded of a metal powder having a higher conductivity and a lower magnetic susceptibility than the iron-based powder, wherein the heterogeneous material is integrally disposed on at least one of a part of a surface of the parent member, or an internal portion of the parent member, or both, and the heterogeneous material diverts an eddy current generated in the parent member.

A shading ring is disposed in a magnetic circuit system. The magnetic circuit system includes a main magnet, a washer, a voice coil and a secondary magnet. The shading ring is located inside the voice coil. The shading ring includes a first ring body and a second ring body. The second ring body is formed by bending a lower end of the first ring body outward. The first ring body includes a first perpendicular portion and a first horizontal portion. A first cavity is formed inside the first perpendicular portion. The secondary magnet is located in the first cavity. The first horizontal portion is fixedly connected to an upward side of the secondary magnet. The shading ring is arranged into a structure having the first ring body and the second ring body.

The present invention discloses a loudspeaker driver comprising a magnet system having at least one gap where in each gap a voice coil assembly is arranged for movement in the gap, wherein either two distinct coils are arranged on the voice coil assembly, one above the other, and the magnet system comprises two pole pieces, one above the other, creating a pair of magnetized areas between said pole pieces and a yoke, such that a magnetic flux field is created between each pole piece and the yoke. In an alternative two concentric gaps are provided, where the voice coil assembly comprises two concentrically arranged sub-voice coils, where each sub-voice coil is provided with a distinct voice coil and the magnet assembly has two concentrically arranged magnet rings arranged with a yoke in the center, such that two concentric gaps are created, and that the voice coil assembly moves substantially orthogonal to the flux fields in the gap(s) and further that at least the part of each pole piece facing the gap(s) is made from a soft magnetic composite (SMC) material.

A yoke for the speaker includes: a parent member molded of an iron-based powder; and a heterogeneous material molded of a metal powder having a higher conductivity and a lower magnetic susceptibility than the iron-based powder, wherein the heterogeneous material is integrally disposed on at least one of a part of a surface of the parent member, or an internal portion of the parent member, or both, and the heterogeneous material diverts an eddy current generated in the parent member.

A speaker device 101 includes vibrating body components constituting a vibrating body, consisting of at least a voice coil 119, a diaphragm 106, and a frame 102, and magnetic circuit components constituting a magnetic circuit, consisting of at least a plate 103, a yoke 104, a magnet 105, and a center pole 112. By winding an insulation coated conductor wire 120 around an outer circumference of any of the magnetic circuit components and connecting one end and the other end of the insulation coated conductor wire, a current flows in the insulation coated conductor wire 120 and makes (+) potentials and () potentials that are mixed on the surface of the magnetic circuit component and cause an eddy current equal to each other instantaneously, so that generation of an eddy current can be suppressed.