Patent attributes
An exciter includes a first yoke having a first accommodation space with a first open end, a second yoke having a second accommodation space with a second open end which faces the first open end, the second open end being spaced from the first open end in a vibration direction. The exciter further includes a first magnetic member accommodated in the first accommodation space, a magnetic core and a coil accommodated in the second accommodation space, the coil wound around the magnetic core, a second magnetic member accommodated in the second accommodation space and located at outside of the coil, and a copper tube wound around the magnetic core and sandwiched between the magnetic core and the coil. The copper tube is capable of suppressing the high frequency impedance of the coil and therefore improves the high frequency performance and the reliability of the exciter.