Bone conduction speaker composite washer magnetic circuit components

Abstract

A bone conduction loudspeaker composite washer magnetic circuit assembly relates to the technical field of audio devices. The assembly includes a yoke and a voice coil. A columnar composite component is provided in the middle of the yoke. The composite component is stacked in sequence from bottom to top by a lower magnet, a composite washer, and an upper magnet. A vibration diaphragm is provided at the upper end of the upper magnet. The voice coil is mounted on the vibration diaphragm through a skeleton. The composite component passes through the inner ring of the voice coil, and the composite component and the voice coil are gap-fitted. The lower magnet and the upper magnet are both permanent magnets, and the polarity of the upper end of the lower magnet is consistent with the polarity of the lower end of the upper magnet. The composite washer is stacked alternately from bottom to top by ferromagnetic washer and non-ferromagnetic washer. The assembly provided by the present invention has low low-frequency harmonic distortion and wide high-frequency response.

Description

Technical Field

[0001] The present invention relates to the technology of audio devices, and in particular to the technology of a bone conduction loudspeaker composite washer magnetic circuit component. Background Art

[0002] Traditional bone conduction speakers use a single washer. Since the magnetic lines of force in the gap between the washer and the yoke are not all distributed in the horizontal direction, the magnetic lines of force in the upper and lower parts of the voice coil have a certain angle with the horizontal direction and are asymmetric. When an alternating electrical signal passes through the voice coil, according to Abe's theorem, the voice coil will vibrate up and down in the gap. For low-frequency signals, the vibration amplitude of the voice coil is large, and the overall non-horizontal asymmetric magnetic field of the upper and lower parts of the voice coil will enter more, causing greater harmonic distortion. The traditional way to solve this problem is to increase the thickness of the magnetic washer so that the voice coil vibrates in the horizontal magnetic field as much as possible. However, since the washer is a magnetic material, the increase in the thickness of the washer will cause the overall self-inductance coefficient of the bone conduction speaker to increase, and the high-frequency attenuation will be greater. Summary of the invention

[0003] In view of the defects existing in the above-mentioned prior art, the technical problem to be solved by the present invention is to provide a bone conduction speaker composite washer magnetic circuit component with small low-frequency harmonic distortion and wide high-frequency response.

[0004] In order to solve the above technical problems, the present invention provides a bone conduction speaker composite washer magnetic circuit assembly, including a yoke and a voice coil, characterized in that: a columnar composite component is provided in the middle of the yoke;

[0005] The composite component is formed by stacking a lower magnet, a composite washer, and an upper magnet in order from bottom to top, a vibration diaphragm is mounted on the upper end of the upper magnet, a voice coil is mounted on the vibration diaphragm through a frame, the composite component passes through the inner ring of the voice coil, and the composite component and the voice coil are in clearance fit;

[0006] The lower magnet and the upper magnet are both permanent magnets, and the polarity of the upper end of the lower magnet is consistent with the polarity of the lower end of the upper magnet;

[0007] The composite washer is formed by alternately stacking N+1 ferromagnetic washers and N non-ferromagnetic washers from bottom to top, and N≥1.

[0008] The bone conduction speaker composite washer magnetic circuit assembly provided by the present invention adopts a method of adding non-ferromagnetic washers between ferromagnetic washers to form a composite washer, so as to increase the thickness of the washers, thereby increasing the height of the horizontal magnetic field across the voice coil and reducing the harmonic distortion of the bone conduction speaker in the low frequency band; and because the total thickness of the ferromagnetic washer is not actually increased and is no longer located in the middle of the voice coil after being divided into two, the self-inductance coefficient of the bone conduction speaker is also reduced, so that the high-frequency response is expanded. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic structural diagram of the composite washer magnetic circuit assembly of the bone conduction speaker according to an embodiment of the present invention. DETAILED DESCRIPTION

[0010] The following is a further detailed description of an embodiment of the present invention in conjunction with the accompanying drawings, but this embodiment is not intended to limit the present invention. All similar structures and similar variations of the present invention should be included in the protection scope of the present invention. The commas in the present invention represent the relationship of and, and the English letters in the present invention are case-sensitive.

[0011] like Figure 1 As shown, a bone conduction speaker composite washer magnetic circuit assembly provided in an embodiment of the present invention comprises a yoke 1 and a voice coil 7, wherein a columnar composite component is provided in the middle of the yoke 1;

[0012] The composite component is formed by stacking a lower magnet 2, a composite washer, and an upper magnet 6 in order from bottom to top. A vibration diaphragm 8 is mounted on the upper end of the upper magnet 6. A voice coil 7 is mounted on the vibration diaphragm 8 through a frame 9. The composite component passes through the inner ring of the voice coil 7, and the composite component and the voice coil 7 are in clearance fit.

[0013] The lower magnet 2 and the upper magnet 6 are both permanent magnets, and the polarity of the upper end of the lower magnet is consistent with the polarity of the lower end of the upper magnet;

[0014] The composite washer is formed by alternately stacking two ferromagnetic washers 3, 5 and a non-ferromagnetic washer 4 from bottom to top. The non-ferromagnetic washer can be made of non-ferromagnetic materials such as copper, aluminum, and plastic, and the ferromagnetic washer can be made of ferromagnetic materials such as iron and iron alloy.

[0015] In other embodiments of the present invention, the composite washer can also be formed by alternately stacking multiple ferromagnetic washers and multiple non-ferromagnetic washers from bottom to top, but the number of ferromagnetic washers should be one more than the number of non-ferromagnetic washers, so that the upper and lower ends of the composite washer are both ferromagnetic washers.

[0016] The working principle of the embodiment of the present invention is as follows:

[0017] Magnetic lines of force ( Figure 1 The dotted line with arrows in the figure is emitted from the lower magnet 2 and the upper magnet 6, passes through the two ferromagnetic washers 3 and 5 respectively, and then passes through the voice coil 7 and enters the yoke 1. Part of the magnetic lines of force return to the bottom of the lower magnet 2 through the yoke 1, and the other part of the magnetic lines of force return to the top of the upper magnet 6 through the space.

[0018] The upper and lower ends of the composite washer are both ferromagnetic washers, and the middle is a non-ferromagnetic washer. After using the composite washer, the height of the horizontal magnetic field across the voice coil can be more than doubled, which can reduce the harmonic distortion and abnormal sound of the bone conduction speaker in the low frequency band. For the user, the actual feeling is that the vibration feeling is significantly reduced and the comfort is significantly improved. Moreover, since the total thickness of the ferromagnetic washer has not actually increased, and after being divided into two, it is no longer in the middle position of the voice coil, the self-inductance coefficient of the bone conduction speaker is also reduced, so that the high-frequency response above 10KHz can be expanded and improved.

Claims

1. A bone conduction speaker composite washer magnetic circuit assembly, comprising a yoke and a voice coil, characterized in that: A columnar composite component is provided in the middle of the yoke; The composite component is formed by stacking a lower magnet, a composite washer, and an upper magnet in order from bottom to top, a vibration diaphragm is mounted on the upper end of the upper magnet, a voice coil is mounted on the vibration diaphragm through a frame, the composite component passes through the inner ring of the voice coil, and the composite component and the voice coil are in clearance fit; The lower magnet and the upper magnet are both permanent magnets, and the polarity of the upper end of the lower magnet is consistent with the polarity of the lower end of the upper magnet; The composite washer is formed by alternately stacking N+1 ferromagnetic washers and N non-ferromagnetic washers from bottom to top, and N≥1.

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