Abstract: Disclosed herein is a vibration actuator. The vibration actuator excites a mass member by interaction between an electric field of a vibration coil provided in an inner space of a case and a magnetic field of a magnetic field unit disposed corresponding to the vibration coil. The vibration actuator comprises an elastic wire having a wire body fixed to the outer surface of the mass member and elastic ends fixed to the inner surface of the case. The elastic wire is connected between the case and the mass member for elastically supporting mass member. The present invention minimizes change of natural frequency due to manufacturing tolerance of raw materials to improve vibration characteristics of the vibration actuator, simplifies and reduces a manufacturing process to improve productivity of the vibration actuator, and improves durability to increase the service life of the vibration actuator.

Abstract: The present invention relates to a multi-function actuator, in which a voice coil vibrates a sound-generating diaphragm in response to an audio signal. A vibration coil is placed on a central axis coaxial with the voice coil for generating vibration in response to the audio signal or a vibration signal. A vibration unit includes a magnet for generating a magnetic field to both of the voice coil and the vibration coil and a yoke having a predetermined mass. The vibration unit is vertically vibrated by an electromagnetic force produced from at least one of the voice coil and the vibration coil. A switch selectively applies the audio signal to the vibration coil. The multi-function actuator can prevent the vibration of the vibration unit during sound generation in response to user's switch selection.

Abstract: A multi-actuator selectively performing audio and vibration generating operations is made by injection molding process of inserting a spring into a case forming an exterior appearance of the multi-actuator. The spring is inserted into the case using an exterior structure integrally formed with the spring, and the exterior structure is cut off from the case after the injection process is finished. In the method of inserting the spring into the case, a plurality of guide holes are formed on the exterior structure and outside springs in a spring array state, and the springs are disposed and inserted into the injection-molding in the array state so that a productivity is improved. Since interference between the springs and the injection molding, deformation of the springs is prevented.