Sound generator

Patent metadata

Field	Value
Publication number	US-11317218-B2
Application number	US-201816975772-A
Country	US
Kind code	B2
Filing date	Dec 25, 2018
Priority date	Feb 26, 2018
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

Abstract

A sound generator comprises a shell, a vibration system and a magnetic circuit system, wherein the shell sequentially accommodates and fixes the vibration system and the magnetic circuit system from top to bottom; the magnetic circuit system comprises a magnetic conductive yoke, and a central magnetic circuit portion and a side magnetic circuit portion that are mounted on an upper surface of the magnetic conductive yoke; a magnetic gap is formed between the central magnetic circuit portion and the side magnetic circuit portion; and at least one of the central magnetic circuit portion and the side magnetic circuit portion is provided with a permanent magnet; the magnetic circuit system is provided with a rear sound hole; a rear cavity in communication with the rear sound hole is provided directly below the magnetic circuit system.

First claim

The invention claimed is:

1. A sound generator, comprising a shell, a vibration system and a magnetic circuit system; wherein,
the shell sequentially accommodates and fixes the vibration system and the magnetic circuit system from a top to a bottom;
the magnetic circuit system comprises a magnetic conductive yoke, a central magnetic circuit portion and a side magnetic circuit portion mounted on an upper surface of the magnetic conductive yoke; wherein a magnetic gap is formed between the central magnetic circuit portion and the side magnetic circuit portion; and at least one of the central magnetic circuit portion and the side magnetic circuit portion is provided with a permanent magnet;
the magnetic circuit system is provided with a rear sound hole;
a rear cavity in communication with the rear sound hole is provided directly below the magnetic circuit system;
the shell further comprises a lower cover plate located at a bottom of the sound generator, wherein the lower cover plate is configured to close the rear cavity; and
at least one support foot extending toward the lower cover plate is provided on the magnetic conductive yoke.

2. The sound generator according to claim 1 , wherein, the magnetic conductive yoke is rectangular, and a corner of the magnetic conductive yoke is provided with a first rear sound hole in communication with the magnetic gap and the rear cavity;
the rear sound hole comprises the first rear sound hole.

3. The sound generator according to claim 1 , wherein, the central magnetic circuit portion comprises a central magnet and a central magnetic conductive plate provided on a top surface of the central magnet; at the central magnetic circuit portion, the magnetic circuit system is provided with a through hole that sequentially penetrates the magnetic conductive yoke and the central magnet as a part of the rear cavity, and a second rear sound hole in communication with the through hole is provided on the central magnetic conductive plate;
the rear sound hole comprises the second rear sound hole.

4. The sound generator according to claim 3 , wherein, the through hole includes a central hole of the magnetic conductive yoke and a central hole of the central magnet, and the support foot is provided at a peripheral position of the central hole of the magnetic conductive yoke.

5. The sound generator according to claim 4 , wherein, the support foot comprises a foot formed by stamping a material located at the central hole of the magnetic conductive yoke before the magnetic conductive yoke is holed.

6. The sound generator according to claim 1 , wherein, there is a gap between the support foot and the lower cover plate.

7. The sound generator according to claim 1 , wherein, the lower cover plate is made of a metal.

8. The sound generator according to claim 1 , wherein,
the shell comprises a straight cylinder-shaped shell body portion with openings at two ends, and the shell body portion accommodates and fixes the vibration system and the magnetic circuit system;
the vibration system comprises a diaphragm and a voice coil fixed below the diaphragm, the diaphragm being fixed on an end surface of a first end opening of the shell body portion; the voice coil is suspended in the magnetic gap;
the shell body portion comprises a first portion corresponding to the vibration system and the magnetic circuit system, and a second portion integrally extending downward from the first portion beyond a bottom surface of the magnetic circuit system;
the lower cover plate is mounted at a second end opening of the shell body portion; and a rear cavity is formed between the second portion of the shell body portion, the bottom surface of the magnetic circuit system and the lower cover plate.

9. The sound generator according to claim 8 , wherein, an outer side of the magnetic circuit system is disposed in close contact with an inner wall of the shell body portion.

10. The sound generator according to claim 8 , wherein, the shell is of a rectangular structure.

11. The sound generator according to claim 8 , wherein, the lower cover plate is selected from the group consisting of a flat plate shape
and a bowl-shaped structure provided with a bottom wall and a side wall.

12. The sound generator according to claim 8 , wherein,
the lower cover plate is made of a metal;
an inner side of an end surface of the second end opening of the shell body portion is provided with a recessed second stepped end surface, the second stepped end surface is provided with a top surface and a side surface for mounting the lower cover plate;
the lower cover plate is of a flat plate shape, an edge of the lower cover plate is provided with a recessed portion recessed toward the rear cavity, the recessed portion abuts on the top surface of the second stepped end surface, a first glue holding groove is formed between the recessed portion and the side surface of the second stepped end surface, and the first glue holding groove is coated with glue to fix the lower cover plate on the shell body portion.

13. The sound generator according to claim 8 , wherein,
the lower cover plate is made of a metal;
an inner side of an end surface of the second end opening of the shell body portion is provided with a recessed second stepped end surface, the second stepped end surface is provided with a top surface and a side surface for mounting the lower cover plate; and
the lower cover plate is of a bowl-shaped structure provided with a bottom wall and a side wall, an end of the side wall of the lower cover plate is bent outward to provide a mounting edge, the mounting edge abuts on the top surface of the second stepped end surface, a second glue holding groove is formed between the mounting edge and the side surface of the second stepped end surface, and the second glue holding groove is coated with glue to fix the lower cover plate on the shell body portion.

14. The sound generator according to claim 8 , wherein,
the lower cover plate is made of a metal;
an inner side of an end surface of the second end opening of the shell body portion is provided with a recessed second stepped end surface, the second stepped end surface is provided with a top surface and a side surface for mounting the lower cover plate; and
a plastic edge is injection-molded on a periphery of the lower cover plate, and the plastic edge is ultrasonically welded to the second end opening of the shell body portion.

15. The sound generator according to claim 1 , wherein, the rear sound hole is provided with a breathable spacer and the rear cavity is filled with a sound absorbing material.

Assignees

• Goertek Inc

Inventors

• Zhao Guodong
• Li Peijun
• Ji Yaqian
• Han Zhilei

Classifications

• H04R1/021

  incorporating only one transducer · CPC title

• H04R15/02 Primary

  Resonant transducers, i.e. adapted to produce maximum output at a predetermined frequency · CPC title

• H04R9/06 Primary

  Loudspeakers · CPC title

• H04R9/025

  Magnetic circuit · CPC title

• H04R9/18

  Resonant transducers, i.e. adapted to produce maximum output at a predetermined frequency · CPC title