Deflection yoke with leaking magnetic field prevention coils

Claim 1

A deflection yoke comprising: a leaking magnetic field preventing member for creating a magnetic field in a direction contrary to that of a leaking magnetic field from a horizontal deflecting coil, the leaking magnetic field preventing member comprising a pair of coils disposed on opposite sides of and facing a flange part of the deflection yoke centering around the center axis of the deflection yoke; a pair of cases, each case for receiving one of the coils, each case comprising coil winding parts disposed on side ends of a space formed in the case, each of the coil winding parts being formed in a semicircular shape; coil drawing holes formed by penetrating the bottom of the coil winding parts for drawing out the coil in the case when the coil is wound on the coil winding parts and thus both side ends of the coil are electrically connected; attaching parts formed on the case for fixing the case on a corresponding part formed on the flange part; cover means for covering the open part of the case connected to the case so as to be rotatable outwardly; cover supporting means formed in the space in the case for supporting the cover means; engaging means formed in the cover means and corresponding to the cover supporting means for fixing the cover means on the cover supporting means; and a plurality of heat emitting holes formed in the cover means to emit the heat generated from the coil, wherein a combining part is formed on each of the coil winding parts, and wedges for attaching each said combining part, respectively are formed on the cover means at a position corresponding to each said combining part.