Patent ID: 7557474

Claim:
An electromagnetic exciter comprising: a magnetic circuit assembly having a cup-shaped yoke with a cylindrical wall and a bottom wall, said magnetic circuit assembly further having a magnet and a top plate that are successively stacked on the bottom wall of said yoke, wherein a magnetic gap is formed between an inner peripheral surface of said cylindrical wall of said yoke and an outer peripheral surface of said top plate; a weight attached to an outer periphery of the cylindrical wall of said yoke; a voice coil inserted into said magnetic gap; a first suspension having a cylindrical side wall portion extending outside said weight coaxially with respect to said cylindrical wall of said yoke, said first suspension further having a spring portion that is integrally formed with a lower end of said cylindrical side wall portion and connected to and support a bottom side of said magnetic circuit assembly so that said magnetic circuit assembly is vibratable in an axial direction of said yoke; an annular support member fitted into an opening at an upper end of said cylindrical side wall portion of said first suspension and secured to an inner peripheral surface of said cylindrical side wall portion; a printed wiring board having wiring that is connected to ends of said voice coil, said printed wiring board being fitted into said opening at said upper end of said cylindrical side wall portion of said first suspension and supported on said annular support member to support said voice coil and; a protector having a cylindrical portion configured to cover an outer peripheral surface of said cylindrical side wall portion of said first suspension, said protector further having a caulking portion that is bent radially inward over an upper end edge of said cylindrical side wall portion of said first suspension to clamp said printed wiring board between said caulking portion and said annular support member.