Patent ID: 9601980
Date: 2017-03-21
CPC Classifications: H02K,H04R

Claim:
1. An electromechanical transducer transducing an electric signal into mechanical vibration, the electromechanical transducer comprising: a structural unit in which at least one pair of magnets, one or more yokes conducting magnetic flux generated by the magnets, and a coil supplied with the electric signal are integrally arranged; a plate-like armature including an inner portion disposed to pass through an internal space of the structural unit and first and second outer portions protruding on both sides from the inner portion, the armature constituting a magnetic circuit with the structural unit via two regions through which components of the magnetic flux flow in directions opposite to each other in the inner portion and being displaced in a direction parallel to a direction of the magnetic flux at the two regions relative to the structural unit; air gaps respectively formed between the two regions and the structural unit; a first elastic unit giving a restoring force to the first outer portion in response to displacement of the armature due to a magnetic force of the magnetic circuit, the first elastic unit being held between the first outer portion and the structural unit; and a second elastic unit giving a restoring force to the second outer portion in response to displacement of the armature due to a magnetic force of the magnetic circuit, the second elastic unit being held between the second outer portion and the structural unit, wherein each of the first and second elastic units includes a pair of elastic members being symmetrically arranged via the armature in a direction of displacement of the armature, the structural unit is provided with a plurality of elastic member attaching portions to which the elastic members are attached, respectively, each of the elastic members has one end engaging the first or second outer portion and another end engaging one of the elastic member attaching portions, and the magnetic flux generated by the magnets is changed in accordance with a displacement of the armature.