Speaker device, audio visual equipment, mobile information processing apparatus, vehicle, and earphone

A speaker device, comprising:

• a magnetic circuit including:
• a plate;
• a magnet having a surface fixed to one surface of the plate, and having no through-hole;
• and a yoke fixed to a surface of the magnet opposite to the surface fixed to the plate, the yoke forming a magnetic gap between itself and an outer peripheral surface of the plate;
• a voice coil disposed in the magnetic gap;
• a diaphragm directly or indirectly fixed to the voice coil;
• a supporting part configured to support the diaphragm;
• and
• a magnetic fluid disposed in at least a space between an outer peripheral surface of the voice coil and an inner peripheral surface of the yoke, wherein
• a rear surface side space between a rear surface of the diaphragm and a front surface of the plate communicates with a space outside the speaker device through a gap for communication which is formed in at least a part, in a peripheral direction of the voice coil, of a space between the outer peripheral surface of the plate and an inner peripheral surface of the voice coil,
• the outer peripheral surface of the plate has a pair of long-side side surfaces opposing each other in a short side direction of the plate, and a pair of short-side side surfaces opposing each other in a long side direction of the plate,
• in the space between the outer peripheral surface of the plate and the inner peripheral surface of the voice coil, the magnetic fluid is disposed outside the long-side side surfaces, and the gap for communication is formed outside at least a part of the short-side side surfaces, and
• portions of the inner peripheral surface of the voice coil, opposing the short-side side surfaces, are more distant from the outer peripheral surface of the plate than portions of the inner peripheral surface of the voice coil opposing the long-side surfaces.

A speaker device, comprising:

• a magnetic circuit including:
• a plate;
• a magnet having a surface fixed to one surface of the plate, and having no through-hole;
• and a yoke fixed to a surface of the magnet opposite to the surface fixed to the plate, the yoke forming a magnetic gap between itself and an outer peripheral surface of the plate;
• a voice coil disposed in the magnetic gap;
• a diaphragm directly or indirectly fixed to the voice coil;
• a supporting part configured to support the diaphragm;
• and
• a magnetic fluid, wherein
• a rear surface side space between a rear surface of the diaphragm and a front surface of the plate communicates with a space outside the speaker device through a gap for communication which is formed in at least a part, in a peripheral direction of the voice coil, of a space between the outer peripheral surface of the plate and an inner peripheral surface of the voice coil,
• the outer peripheral surface of the plate has a pair of long-side side surfaces opposing each other in a short side direction of the plate, and a pair of short-side side surfaces opposing each other in a long side direction of the plate,
• in the space between the outer peripheral surface of the plate and the inner peripheral surface of the voice coil, the magnetic fluid is disposed outside the long-side side surfaces, and the gap for communication is formed outside at least a part of the short-side side surfaces,
• projections projecting outward are formed at a part of the short-side side surfaces, and
• in the space between the outer peripheral surface of the plate and the inner peripheral surface of the voice coil, the magnetic fluid is disposed outside top end surface of the projections.

A speaker device, comprising:

• a magnetic circuit including:
• a plate;
• a magnet having a surface fixed to one surface of the plate, and having no through-hole;
• and a yoke fixed to a surface of the magnet opposite to the surface fixed to the plate, the yoke forming a magnetic gap between itself and an outer peripheral surface of the plate;
• a voice coil disposed in the magnetic gap;
• a diaphragm directly or indirectly fixed to the voice coil;
• a supporting part configured to support the diaphragm;
• and
• a magnetic fluid, wherein
• a rear surface side space between a rear surface of the diaphragm and a front surface of the plate communicates with a space outside the speaker device through gaps for communication which are formed in at least a part, in a peripheral direction of the voice coil, of a space between the outer peripheral surface of the plate and an inner peripheral surface of the voice coil,
• the plate has a planar shape with cutouts at four corners, and
• in the space between the outer peripheral surface of the plate and the inner peripheral surface of the voice coil, the cutouts form the gaps for communication, and the magnetic fluid is disposed at portions other than the cutouts.