Urban transport quiet electric motor with acoustic insulation, inside insulation audible energy is transformed by friction into heat energy which is evacuated from an exterior metal protective cover

摘要

Transformation of acoustic mechanical energy into heat is done by consecutive dry or viscous frictional rubbing due to micro-displacements inside the acoustic material or of the acoustic insulation structure. The component of the acoustic material is a resilient structure having a physical form which permits friction by mutual contact. It is a mattress formed by juxtaposition of packets, blocks, padding, cushions and thick bands (14) of acoustic insulation material. The quiet motor is of the type having a rotor (7) exterior to the stator (1). The exterior lateral surface (16) of the rotor mechanical assembly is surrounded by a jacket of acoustic insulation material covered by a metallic protection envelope (13). Audible acoustic frequencies are converted into heat by friction caused by rubbing in the acoustic insulation material. The heat is transferred to the exterior by the composite metallic protection envelope surrounding the acoustic jacket.