Fixing structure of radial lead of rotating electrical machine

1. A fixing structure of a radial lead of a rotating electrical machine, which is furnished with a function of connecting slip rings provided to a rotation shaft of a rotor and axial leads provided inside a center hole of the rotation shaft and supplying a current to a rotor coil and a function of preventing a leakage of a refrigerant gas within the rotation shaft, wherein:

the radial lead is inserted into a radial lead hole penetrating through the rotation shaft in a radial direction from the center hole, the inner surface of the radial lead hole being free of screw threads, and a male screw formed at one end is threaded into a female screw formed in the axial lead and fixed therein while the other end is electrically connected to the slip ring; and

a sealing member installed to a step portion of the radial lead hole is fastened, via a spacer, by a fastening nut threaded into the other end of the radial lead, so that a side of the center hole is maintained airtight from an outside.

2. The fixing structure of a radial lead of a rotating electrical machine according to claim 1 , wherein:

the sealing member is fastened with a managed predetermined fastening force.

3. The fixing structure of a radial lead of a rotating electrical machine according to claim 2 , wherein:

the fastening force is such that a sink-in amount of the sealing member is 2.7 mm or more.

4. The fixing structure of a radial lead of a rotating electrical machine according to claim 1 , wherein:

a tapered surface continuing to an inner peripheral surface of the radial lead hole in which the sealing member is installed and spreading toward an external opening end is formed;

the fixing structure has a ring-shaped tapered member that fits to the tapered surface; and

the tapered member is interposed between the sealing member and the spacer.