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A ventilation scheme for rotor windings in a dynamoelectric machine includes passages axially extending through the axial end turn conductors of the windings. Each axially extending conductor is an integral, single bar of metal having a groove thereon which defines the passages in cooperation with t

A ventilation scheme for rotor windings in a dynamoelectric machine includes passages axially extending through the axial end turn conductors of the windings. Each axially extending conductor is an integral, single bar of metal having a groove thereon which defines the passages in cooperation with the turn insulation interposed between each conductor and the underlying and overlaying conductors. Circumferential end turn conductors are mechanically and electrically attached to the axial end turn conductors by reinforcing plates. Circumferential passages through the circumferential end turn conductors allow gas to flow between an end turn region and an isolated low pressure area. The centrifugal pumping action developed by the rotation of the rotor draws gas from the end turn region through the passages and to the periphery of the rotor body.

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1. In combination with a rotor for a gas cooled dynamoelectric machine, said rotor inlcuding a rotor body defining at least a pair of axial winding slots, one of the at least a pair of winding slots respectively circumferentially disposed at the periphery of the rotor body on respective sides of a p

1. In combination with a rotor for a gas cooled dynamoelectric machine, said rotor inlcuding a rotor body defining at least a pair of axial winding slots, one of the at least a pair of winding slots respectively circumferentially disposed at the periphery of the rotor body on respective sides of a pole portion of the rotor body and the rotor body further defining at least one gas discharge flue extending from a pole face of the rotor body to the periphery of the rotor body, the pole face disposed on an axial end of the rotor body, said rotor further including a spindle coupled to the axial end of the rotor body, said spindle for rotatably mounting said rotor, a rotor winding cooling system comprising: a plurality of axially extending electrical conductors disposed in the winding slots, at least a portion of the axial conductors extending beyond said rotor body to form an axial end turn conductor, at least one of said plurality of axial conductors disposed on each side, respectively, of said pole face, each axial conductor including a first bar of metal, said first bar having a first substantially longitudinal groove for forming a passageway for receiving a first portion of gas, said passageway defined in part by insulation to be interposed between axial conductors within said winding slot for respectively electrically insulating each axial conductor within said winding slot from other axial conductors within said winding slot, respectively, said passageway including first port means for introducing gas into the passageway and second port means for withdrawing gas from the passageway a plurality of circumferential end turn electrical conductors for respectively electrically connecting the respective at least one of said plurality of axial conductors on one side of the pole face with the respective at least one of said plurality of axial conductors on the other side of the pole face, respectively, for forming a respective current carrying loop, each circumferential end turn conductor including a second bar of metal having a second substantially longitudinal groove for forming a passage for receiving a second portion of gas, said passage defined in part by a member coupled to the second bar, said plurality of circumferential end turn conductors arcuately spanning said pole portion and stacked with electrical insulation interposed between adjacent circumferential end turn conductors, respectively, said passage including third port means for introducing gas into the passage and fourth port means for withdrawing gas from the passage; a retaining ring affixed to said rotor body and circumferentially surrounding said axial and circumferential end turn conductors for maintaining said axial and circumferential end turn conductors in fixed spatial relationship against centrifugal and circumferential forces; a centering ring affixed to said retaining ring and axially spaced from said rotor body to substantially enclose an end turn region about said axial and circumferential end turn conductors, said end turn region defined by the axial end of said rotor body, the radial inner surface of said retaining ring, the radial outer surface of the spindle and the axial surface of said centering ring opposing the axial end of said rotor body, said centering ring further defining an annular space between the radially inward portion of said centering ring and the radially outer portion of the spindle, said annular space for introducing flow of the first and second portion of gas into said end turn region; and blocking means disposed within said end turn region for preventing gas flow communication between a portion of said end turn region and the balance of said end turn region for forming a low pressure area in said portion of said end turn region, said low pressure area arcuately spanning a predetermined portion of said pole face and a predetermined arcuate portion of said plurality of circumferential end turn conductors, said low pressure area further axially spanning said circumferential end turn conductors, and said low pressure area in gas flow communication with said gas discharge flue, wherein centrifugal pumping action during rotation of said rotor encourages gas to flow through said discharge flue to the periphery of said rotor, thereby reducing the pressure within the low pressure area of said end turn region with respect to the pressure in the balance of said end turn region; wherein the first and third port means are in gas flow communication with the balance of said end turn region, the second port means is in gas flow communication with the periphery of said rotor and the fourth port means is in gas flow communication with the low pressure area of said end turn region. 2. A cooling system as in claim 1 wherein at least one of said axial end turn conductor includes a first radial orifice in gas flow communication with the respective first port means of the respective axial conductor and respective interposed insulation having a second radial orifice, said first and second orifices substantially aligned with other orifices through the overlaying and underlying axial end turn conductors and respective insulation disposed in the same winding slot to form a substantially radial vent extending from the radially inner axial end turn conductor to the radially outer axial end turn conductor, wherein said vent enables gas to flow from the balance of said end turn region, through said radial vent and said passageway to said periphery of said rotor body. 3. A cooling system as in claim 2 wherein each first orifice of each axial end turn conductor is in gas flow communication with the respective first port means of the respective axial conductor. 4. A cooling system as in claim 1 further including reinforcing means electrically and mechanically connecting at least one circumferential end turn conductor to a corresponding axial end turn conductor, said reinforcing means including an inboard gusset spaced below and above the top and bottom surfaces of said reinforcing means, respectively. 5. A cooling system as in claim 4 wherein said rotor includes a plurality of pole portions and a respective plurality of pole faces; each pole face having an associated gas discharge flue respectively terminating thereon and defined in part by said rotor body; and a plurality of low pressure areas defined in part by a respective plurality of blocking means; each of said respective plurality of blocking means including a pair of partitions extending axially between the respective pole face and the inboard surface of said centering ring, said partitions sealingly engaging the circumferential end turn conductors which intersect said partitions, and sealingly engaging the radially inner surface of said retaining ring and the radially outer surface of the spindle, said partitions thereby establishing the arcuate span of the respective ones of the plurality of low pressures areas, each of said respective plurality of blocking means further including a radially disposed end plate bridging said annular space between said centering ring and the radially outer surface of the spindle, and said end plate sealingly engaging the outboard ends of both partitions to substantially isolate the respective low pressure area from the balance of said end turn region and the ambient environment. 6. A cooling system as in claims 1, 2, 3, 4, or 5 wherein said member includes a single bar of metal. 7. A cooling system as in 1, 2, 3, 4, or 5 wherein said member includes a single integral bar of metal having a first flat surface coextensive with the second substantially longitudinal groove for defining in part said passage and a second flat surface for receiving the insulation. 8. A cooling system as in claim 1, 2, 3, 4, or 5 wherein each circumferential end turn conductor having a radial orifice open to its respective inlet and aligned with similar orifices through said interposed insulation to form a radial venthole, said radial venthole allowing gas to flow from the balance of said end turn region to said low pressure area of said end turn region; and each circumferential end turn conductor having a first radial aperture in gas flow communication with the respective fourth port means and each first radial aperture aligned with second radial apertures through said interposed insulation to form a radial chimney, said radial chimney for permitting communication of gas from each respective passage to said low pressure area of said end turn region. 9. A cooling system as in claim 4 wherein said passageway and passage terminate before extending into said reinforcing means. 10. An electrically conductive coil for a gas cooled dynamoelectric machine, said machine including a rotor defining at least two axially extending slots respectively disposed on respective sides of a pole portion of the rotor, said slots for receiving at least a portion of said coil, said coil comprising: a pair of slot lying segments, a respective one of said pair for disposition within the respective slots, at least one of said slot lying segments including a single electrically conductive bar, said bar having a first longitudinal groove for forming a passageway, the passageway defined in part by the surface of electrical insulation disposable on said bar; reinforcing means respectively coupled to said at least one of said pair of said slot lying segments at one end of the bars; bars, said reinforcing means having an upper and lower surface and an end turn segment coupled to said reinforcing means so as to form a conrer formed in part by said reinforcing means, said end turn segment including a first elongated electrically conductive member, said first elongated electrically conductive member having a second longitudinal groove, and said end turn segment further including a second elongated electrically conductive member coupled to said first member for sealingly engaging said first member to form a passage wherein the passage includes the second groove and further, wherein the passageway and the passage respectively include a gas input and a gas output, respectively. 11. The coil as in claim 10 wherein said reinforcing means includes a gusset disposed at the corner, said gusset for providing structural rigidity between said end turn segment and said at least one of said pair of slot lying segments, wherein said gusset is further disposed intermediate the upper and lower surface of said reinforcing means. 12. The coil as in claim 11 wherein said at least one of said pair of slot lying segments, said end turn segment and said reinforcing means form a substantially squared-off contour at the exterior of the corner, thereby facilitating placement of the insulation on said at least one of said pair of slot lying segments, said end turn segment and said reinforcing means. 13. The coil as in claim 10 wherein said reinforcing means inhibits gas flow communication between said passageway and said passage.