Patent ID: 7530757

Claim:
An insulated coupling structure connecting a generator rotor and a steam turbine rotor in an electrically insulated state, comprising: a generator-side flange provided on an end of said generator rotor, a steam turbine-side flange provided on an end of a shaft extending from said steam turbine rotor, an inter-flange member that is held between said generator-side flange and said steam turbine-side flange, a connecting bolt for tightening an area between said generator-side flange and said steam turbine-side flange with said inter-flange member held therebetween, wherein said inter-flange member comprises a spacer and a pair of rings which sandwich the spacer, and insulating parts each consisting of an alumina flame coated layer are respectively provided to said rings for interrupting galvanization between said generator-side flange and said steam turbine-side flange, and said rings are engaged with concavities formed in the flanges respectively, to enable adjustment of the generator rotor and the steam turbine rotor along a single axis.