Sealing means for liquid cooled rotors for dynamoelectric machines

Claim 2

In a dynamoelectric machine, a rotor member including shaft portions and having passages for circulation of a liquid coolant therethrough, said passages including entrance and discharge passages in the shaft portions for introducing coolant into the rotor and discharging it Therefrom, sealing means associated with said entrance and discharge passages, each of said sealing means comprising a stationary coolant chamber surrounding the shaft and containing coolant at a predetermined pressure, said coolant chamber having a small clearance with the shaft, a stationary seal ring encircling the shaft with a small clearance adjacent said coolant chamber, means for introducing a sealing liquid into the clearance between said seal ring and the shaft, said sealing liquid being maintained at a pressure not exceeding the pressure of the coolant liquid, a stationary chamber surrounding the shaft adjacent the seal ring for receiving liquid flowing between the ring and the shaft, means for sealing said last-mentioned chamber, and means for draining liquid from the last-mentioned chamber.

Claim 3

The combination defined in claim 1 in which the last-mentioned chamber is maintained at atmospheric pressure and has labyrinth seal means between the chamber and the shaft.

Claim 4

The combination defined in claim 2 including another chamber surrounding the shaft adjacent the labyrinth seal means and containing air at greater than atmospheric pressure.

Claim 5

The combination defined in claim 1 in which said seal ring is contained in an annular chamber adjacent the coolant chamber and has radial openings therethrough, and means for applying sealing liquid to said annular chamber to flow through said openings to the clearance between the seal ring and the shaft.

Claim 6

In a dynamoelectric machine, a rotor member having passages for circulation of a liquid coolant therethrough, said rotor member having shaft portions at each end thereof, said passages including an entrance passage comprising an open tube extending coaxially from one of said shaft portions and rotatable therewith, said passages further including opposed radial discharge passages in one of said shaft portions communicating with an axial passage to discharge coolant therefrom, entrance seal means associated with said rotatable tube, discharge seal means associated with said discharge passages, each of said seal means including a stationary coolant chamber surrounding the rotor member with a small clearance and containing coolant under pressure, a stationary seal ring adjacent the coolant chamber and encircling the rotor member with a small clearance, means for introducing a sealing liquid into the clearance between the seal ring and rotor at a pressure not exceeding the pressure of coolant in the coolant chamber, and means for containing and draining off sealing liquid flowing between the seal ring and the rotor.

Claim 7

In a dynamoelectric machine, a rotor member having passages for circulation of a liquid coolant therethrough, said rotor member having shaft portions at each end thereof, said passages including an entrance passage comprising an open tube extending coaxially from one of said shaft portions and rotatable therewith, said passages further including opposed radial discharge passages in one of said shaft portions communicating with an axial passage to discharge coolant therefrom, entrance seal means associated with said rotatable tube, discharge seal means associated with said discharge passages, each of said seal means including a stationary coolant chamber surrounding the rotor member with a small clearance and containing coolant under pressure, a stationary seal ring adjacent the coolant chamber and encircling the rotor member with a small clearance, means for introducing a sealing liquid into the clearance between the seal ring and rotor at a pressure not exceeding the pressure of coolant in the coolant chamber, and means for containing and draining off sealing liquid flowing between the seal ring and the rotor.

Claim 8

The combination defined in claim 5 in which each seal means includes an annular chamber adjacent the seal ring for receiving sealing liquid, said annular chamber being sealed and maintained at substantially atmospheric pressure, and means for draining sealing liquid from the annular chamber.

Claim 9

The combination defined in claim 5 in which said entrance seal means comprises a stationary coolant chamber enclosing the open end of said rotatable tube and containing coolant under pressure, a stationary annular chamber adjacent said coolant chamber containing said seal ring, means for introducing sealing liquid through said annular chamber to the seal ring at a pressure not exceeding the pressure of the coolant, a second annular chamber adjacent the seal ring for receiving sealing liquid, said second annular chamber being maintained at a pressure below the pressure of the sealing liquid, means for sealing the second annular chamber, and means for draining sealing liquid therefrom.

Claim 10

The combination defined in claim 7 including a labyrinth seal between the second annular chamber and the rotor, and another chamber adjacent the labyrinth seal containing air at a higher pressure than the pressure in the second annular chamber.

Claim 11

The combination defined in claim 5 in which said discharge seal means comprises a stationary coolant chamber enclosing said discharge passages, said coolant chamber containing coolAnt under pressure discharged from said passages and having means for draining coolant therefrom, a stationary seal ring encircling the shaft on each side of the coolant chamber, stationary annular chambers adjacent the coolant chamber on each side thereof and containing the seal rings, means for introducing sealing liquid through said annular chambers to the seal rings at a pressure not exceeding the pressure in the coolant chamber, other annular chambers surrounding the shaft adjacent each of said seal rings for receiving sealing liquid, each of said other chambers being maintained at a pressure below the pressure of the sealing liquid, means for sealing said other chambers, and means for draining sealing liquid therefrom.

Claim 12

The combination defined in claim 9 including a labyrinth seal between each of said other chambers and the shaft, and a chamber adjacent each labyrinth seal containing air at a higher pressure than the pressure in said other chambers.

Claim 13

A shaft seal for preventing escape of liquid along a rotating shaft, said seal comprising a stationary chamber through which the shaft passes, said chamber containing liquid under pressure, a stationary seal ring encircling the shaft with a small clearance adjacent said chamber, means for introducing a flow of sealing liquid through said clearance between the seal ring and the shaft, the pressure of the sealing liquid not exceeding the pressure of the liquid in said chamber, a stationary annular chamber surrounding the shaft adjacent the seal ring for receiving said sealing liquid, said annular chamber being maintained at a pressure below the pressure of the sealing liquid, means for sealing the annular chamber, and means for draining liquid therefrom.

Claim 14

A shaft seal for preventing escape of liquid along a rotating shaft, said seal comprising a stationary chamber through which the shaft passes, said chamber containing liquid under pressure, a stationary seal ring encircling the shaft with a small clearance adjacent said chamber, means for introducing a flow of sealing liquid through said clearance between the seal ring and the shaft, the pressure of the sealing liquid not exceeding the pressure of the liquid in said chamber, a stationary annular chamber surrounding the shaft adjacent the seal ring for receiving said sealing liquid, said annular chamber being maintained at a pressure below the pressure of the sealing liquid, means for sealing the annular chamber, and means for draining liquid therefrom.

Claim 15

A shaft seal as defined in claim 11 in which the means for sealing the annular chamber includes a labyrinth seal between the chamber and the shaft and another chamber encircling the shaft adjacent the labyrinth seal and containing air at a pressure higher than the pressure in the annular chamber.