Multi-layer voice coil plate and flat type speaker comprising the same

A multilayer voice coil plate comprising:

• a pair of base substrates facing each other;
• inner voice coil pattern layers formed on both surfaces of each of the pair of base substrates, respectively;
• insulating films covering the respective surfaces of the inner voice coil pattern layers on both surfaces of each of the pair of base substrates;
• and
• an outer voice coil pattern layer formed on each of the insulating films of outer surfaces of the pair of base substrates, with an adhesive layer interposed therebetween,
• wherein two insulating films on inner surfaces of the pair of base substrates, facing each other, are bonded to each other with an adhesive layer.

A flat speaker comprising:

• a multilayer voice coil plate;
• a vibration plate vertically coupled to an upper edge of the multilayer voice coil plate, and configured to vibrate in a direction parallel to the multilayer voice coil plate;
• a first input terminal installed adjacent to a first end of the multilayer voice coil plate;
• and
• a second input terminal installed adjacent to a second end of the multilayer voice coil plate,
• wherein the multilayer voice coil plate comprises:
• a first-type voice coil pattern layer formed in the shape of a track and connected from a first outer via hole outside the track to an inner via hole disposed in the track;
• and
• a second-type voice coil pattern layer formed in the shape of a track and connected from a second outer via hole outside the track to an inner via hole disposed in the track,
• wherein the plurality of first-type voice coil pattern layers and the plurality of second-type voice coil pattern layers are stacked so as to be insulated from each other, and the first outer via holes and the second outer via holes are electrically connected through interlayer conductors, respectively,
• wherein the inner via holes of the plurality of first-type voice coil pattern layers and the inner via holes of the plurality of second-type voice coil pattern layers are vertically aligned at the same position, and electrically connected to each other through an interlayer conductor.

A flat speaker comprising:

• a multilayer voice coil plate;
• a vibration plate vertically coupled to an upper edge of the multilayer voice coil plate, and configured to vibrate in a direction parallel to the multilayer voice coil plate;
• a first input terminal installed adjacent to a first end of the multilayer voice coil plate;
• and
• a second input terminal installed adjacent to a second end of the multilayer voice coil plate,
• wherein the multilayer voice coil plate comprises:
• a pair of base substrates facing each other;
• inner voice coil pattern layers formed on both surfaces of each of the pair of base substrates, respectively;
• insulating films covering the respective surfaces of the inner voice coil pattern layers on both surfaces of each of the pair of base substrates;
• and
• an outer voice coil pattern layer formed on the insulating film of each of outer surfaces of the pair of base substrates, with an adhesive layer interposed therebetween,
• wherein two insulating films of inner surfaces of the pair of base substrates, facing each other, are bonded to each other with an adhesive layer.