Patent ID: 8721513

Claim:
An electric motor provided with a hollow rotating drive shaft rotatably driven by said motor, said drive shaft extending along the central axis of said motor and mounted on bearings for rotation about said central axis of said motor, said drive shaft having first and second ends, said electric motor further comprising a stationary fluid supply line and a rotating union which joins said fluid supply line and said first end of said drive shaft to thereby provide sealed fluid communication between said fluid supply line and the hollow interior of said first end of said drive shaft for supplying fluid to the hollow interior of said first end of said drive shaft, whereby a fluid is supplied under pressure from said stationary fluid supply line to the rotating second end of said hollow drive shaft when said electric motor is rotating said drive shaft; wherein said hollow drive shaft further comprises a hollow conduit mounted coaxially within and secured to said hollow drive shaft for carrying said fluid from said first end of said drive shaft to said second end of said drive shaft, said hollow conduit having a first and second end, whereby said rotating union joins said fluid supply line to said first end of said hollow conduit to thereby provide sealed fluid communication between said fluid supply line and the hollow interior of said first end of said hollow conduit for supplying fluid to the hollow interior of said first end of said drive shaft, whereby a fluid is supplied under pressure from said stationary fluid supply line to the rotating second end of said hollow drive shaft when said electric motor is rotating said drive shaft.