Bone-Conduction Speaker Housing to Prevent Driver Displacement

The patent introduces a separate limiting structure (cylindrical housing with sealing plates) that divides the system into two functional zones: a vibration zone where the driving assembly can move freely to produce sound, and a limiting zone that prevents excessive displacement. This segmentation allows the driving assembly to vibrate adequately for sound production while being constrained within safe boundaries to prevent element displacement.

The patent employs a limiting structure (cylindrical housing with sealing plates at both ends) as an intermediary element between the driving assembly and the external environment. This intermediary structure provides mechanical constraint to the driving assembly, preventing the bone-conduction elements from being displaced during vibration while still allowing sufficient movement for sound production.

The limiting structure is designed with specific local characteristics: the cylindrical housing provides radial constraint while the sealing plates at both ends provide axial constraint. This localized constraint approach ensures that the driving assembly is restricted only in the directions that would cause element displacement, while maintaining vibration freedom in the directions needed for sound production.

The patent applies partial constraint through the limiting structure - it provides sufficient constraint to prevent bone-conduction element displacement and extend service life, but deliberately avoids excessive constraint that would completely restrict vibration. The sealing plates and cylindrical housing create a balanced constraint system that extends service life without overly limiting the driving assembly's vibration capability.