Flexible printed circuit board and speaker using same
The present disclosure discloses a flexible printed circuit board having a high reliability and includes an elastic arm, and a first end and a second end respectively extending from two ends of the elastic arm. A part of the elastic arm is provided with a thinning portion for changing stiffness distributions of the elastic arm during vibrating. The present disclosure also discloses a speaker using the flexible printed circuit board.
1 . A flexible printed circuit board, comprising an elastic arm, and a first end and a second end respectively extending from two ends of the elastic arm, wherein a part of the elastic arm is provided with a thinning portion for changing stiffness distributions of the elastic arm in order to achieve a stress balance on the entire elastic arm during vibration, wherein the flexible printed circuit board comprises a coating layer and a conductive layer combined with the coating layer, and the thinning portion is formed by thinning the coating layer of the part of the elastic arm.
2 . A speaker, comprising the flexible printed circuit board as described in claim 1 .
3 . The speaker as described in claim 2 , further comprising a frame, a vibration system fixed to the frame, and a magnetic circuit system fixed to the frame, wherein the vibration system comprises a diaphragm and a voice coil for driving the diaphragm to vibrate and emit sounds, the magnetic circuit system comprises a bottom plate, a first magnet disposed on the bottom plate, and a second magnet disposed on the bottom plate and spaced apart from the first magnet for forming a magnetic gap, the second magnet is provided with a first gap, the flexible printed circuit board is arranged in the first gap, the first end of the flexible printed circuit board is fixed to the frame, the second end of the flexible printed circuit board is fixed to the voice coil.
4 . The speaker as described in claim 3 , wherein an amount of the second magnets is four, the four second magnets surround the first magnet, each two adjacent second magnets form the first gap.
5 . The speaker as described in claim 3 , wherein the magnetic circuit system further comprises a first yoke disposed on the first magnet and a second yoke disposed on the second magnet, the second yoke is provided with a second gap corresponding to the first gap.