Sound-generating device

A sound-generating device, comprising:

• a cone frame;
• a vibration system fixed to the cone frame;
• and
• a magnetic circuit system fixed to the cone frame and configured to drive the vibration system to vibrate;
• wherein the vibration system comprises a diaphragm, a first voice coil, a second voice coil and a third voice coil;
• the first voice coil, the second voice coil and the third voice coil are arranged spaced apart from each other, and are configured to drive the diaphragm to vibrate;
• the diaphragm comprises a first surround in a ring shape, a second surround arranged spaced apart at an inner side of the first surround, and a vibration portion in a ring shape;
• an outer periphery of the first surround is fixed to the cone frame;
• an inner periphery of the first surround is fixed to an outer periphery of the vibration portion;
• a periphery of the second surround near the first surround is fixed to an inner periphery of the vibration portion;
• the first voice coil, the second voice coil and the third voice coil are connected in series, and are fixed to a side of the vibration portion near the magnetic circuit system;
• and
• a side of the magnetic circuit system near the vibration system is provided with a first magnetic gap, a second magnetic gap and a third magnetic gap spaced apart from each other;
• the first magnetic gap and the third magnetic gap are respectively located at opposite sides of the second magnetic gap;
• the first voice coil is configured to be insertedly suspended in the first magnetic gap;
• the second voice coil is configured to be insertedly suspended in the second magnetic gap;
• and the third voice coil is configured to be insertedly suspended in the third magnetic gap;
• the magnetic circuit system comprises a bottom plate, a first primary magnet, a second primary magnet, a third primary magnet, a plurality of first secondary magnets, a plurality of second secondary magnets and a plurality of third secondary magnets;
• the first primary magnet, the second primary magnet and the third primary magnet are stacked in sequence and fixed to a side of the bottom plate close to the vibration system, and are arranged spaced apart from each other;
• the plurality of first secondary magnets are stacked and fixed to the bottom plate, and are arranged around the first primary magnet;
• the plurality of second secondary magnets are stacked and fixed to the bottom plate, and are arranged around the second primary magnet;
• and the plurality of third secondary magnets are stacked and fixed to the bottom plate, and are arranged around the third primary magnet;
• and
• the plurality of first secondary magnets are each spaced from the first primary magnet to form the first magnetic gap;
• the plurality of second secondary magnets, one of the plurality of first secondary magnets close to the second primary magnet and one of the plurality of third secondary magnets close to the second primary magnet are each spaced from the second primary magnet to form the second magnetic gap;
• and the plurality of third secondary magnets are each spaced from the third primary magnet to form the third magnetic gap;
• the magnetic circuit system further comprises a first center magnet stackedly fixed to a side of the second primary magnet close to the vibration system, and a second center magnet stackedly fixed to a side of the first center magnet close to the vibration system;
• and the second surround is also fixed to a side of the first center magnet away from the second primary magnet.