The invention discloses an air bag expansion in-ear earphone based on external ear special-shaped contour
adaptation. The air bag expansion in-ear earphone comprises a bottom shell, a
loudspeaker, an air bag, a face shell and an elastic self-
locking mechanism. The outer contour face of the bottom shell is matched with an outer lug special-shaped structure, the outer side face is combined with an air bag, the face shell is connected with the bottom shell through a connecting column, an expansion-shrinkage hole is formed in the center of the face shell, and the air bag partially penetrates through the hole. The elastic self-
locking mechanism is connected with the outer cover and the bottom shell, penetrates through the telescopic channel of the air bag and comprises a sliding sleeve, a sliding block, a reset spring and a traction rod, and a sliding groove of the sliding block is provided with an upper clamping groove and a lower clamping groove. In a
normal state, the elastic self-
locking mechanism extends, and the air bag contracts; during wearing, the outer cover is pressed, the elastic self-locking mechanism is compressed and locked, and the outer cover extrudes the air bag to expand in the circumferential direction of the bottom shell to fit the outline of the
outer ear. Non-auditory meatus intrusive wearing is achieved, the
loudspeaker is suspended and does not make contact with the auditory meatus, the air bag is sealed to form an
air layer, the physical
noise reduction function and the air pressure absorption function are achieved, oppression is avoided, the earphone is adaptive to different
outer ear contours, and the earphone is light, easy to store and good in comfort and
sound quality.