PROBLEM TO BE SOLVED: To make a supply part and its vicinity visible, related to an air cooling motor of which a rotating shaft comprises a through hole which a fluid flows.
SOLUTION: A rotary joint (fluid supply part) 3 is provided on the rear side of a motor body 1 of which a rotating shaft comprises a through hole 10, through a rotary joint fitting housing 2. A fluid is fed into the rotary joint 3 through a hose 11. Cooling air channel 13 is provided to an appropriate point of the motor body 1. The rotary joint 3 is surrounded with a tubular member 20 fitted detachably, and a cooling air flows from the cooling air channel 13 to a cooling fan 4 through the inside of the tubular member 20. A part of the tubular member 20 is provided with a window (abcd) stopped with a translucent member 21 with the rotary joint 3 and its vicinity visible from outside. Breakage or leakage of fluid of the rotary joint 3 is found in an early stage. A cooling air channel may be disposed inside the tubular member with the window of the tubular member as an opening for ventilation.
COPYRIGHT: (C)2004,JPO