Salient pole rotor for a dynamoelectric machine

• US 5,086,246 A
• Filed: 02/05/1991
• Issued: 02/04/1992
• Est. Priority Date: 02/22/1990
• Status: Expired due to Term

• Current Assignee: General Electric Canada (GE Aerospace)
• Original Assignee: General Electric Canada (GE Aerospace)
• Inventors: Saidi, Nick N., Young, John M., Dymond, James H.
• Primary Examiner(s): SKUDY, ROBERT
• Application Number:
  US07/650,540
• Time in Patent Office: 364 Days
• Field of Search: 310/269, 310/261, 310/58, 310/59, 310/61, 310/62, 310/63, 310/64, 310/65, 310/60 R, 310/60 A, 310/91, 310/42, 310/254, 310/218, 310/52, 310/208, 310/194
• US Class Current: 310/269
• CPC Class Codes: H02K 1/325 between salient poles
• CPC Class Codes: H02K 9/06 with fans or impellers driven by the machine shaft
• CPC Class Codes: Y10S 174/21 Rotor

Abstract

A dynamoelectric machine has a stator with a stator core and a plurality of spaced apart radially extending ventilation ducts. A rotor mounted for rotation within the stator has a shaft with a plurality of salient poles. Each salient pole has a winding on it and each pole with its winding constitutes a pole member. Adjacent pole members define between them an interpolar space. Cooling air enters each interpolar space from each end when the machine is operating, moves generally axially as portions of the air change direction to move radially outwards through the air gap separating the rotor and stator and then through the ventilation ducts. The air flow, in a radial outward direction, tends to be less at the ends of the rotor and through the ventilation ducts adjacent the ends of the stator. The invention places a baffle at each end of each interpolar space. The baffle is in a generally radial plane and has an outward edge adjacent the outer limit of the interpolar space as defined by the tips of the poles, and an inward edge spaced from the bottom of the interpolar space. The baffle improves the air flow radially outwards adjacent the ends of the rotor and the stator.

Claims

1. A dynamoelectric machine having a salient pole rotor with an axially extending shaft mounted for rotation within a stator, the rotor having no fan associated therewith, the rotor and stator defining therebetween an air gap, the stator having a stator core with stator windings thereon, and a plurality of spaced apart ventilation ducts located between axially opposing ends of the stator and extending radially from the air gap to an exhaust region, said dynamoelectric machine being cooled by a cooling gas circulated through said rotor and said stator, said rotor comprising

a plurality of axially extending, spaced apart poles, mounted on said shaft, each pole having a base where it mounts to said shaft and a pole tip radially outward of said base and defining a periphery of rotation,

a winding on each said pole, each said pole and respective winding thereon forming a pole member, adjacent pole members defining therebetween an interpolar space,

at least one coil bracket in each interpolar space, each said coil bracket having a central portion with extending arm portions,

means for fastening each said coil bracket to said shaft at the central portion of said bracket, respective arm portions of said coil bracket engaging adjacent surfaces of the windings of adjacent pole members for aiding in securing said windings,

a baffle at each end of each said interpolar space, each of said baffles being in a substantially radial plane and extending between adjacent ones of said pole members, each said baffle having a radially outward edge adjacent said periphery of rotation and an inward edge spaced outwardly from said bases of adjacent ones of said pole members,

with rotation of said rotor said baffles tending to increase at each end of said rotor static pressure of said cooling gas within said machine in said air gap adjacent the ends of said stator, thereby improving flow of said cooling gas radially outwards through said air gap and said ventilation ducts adjacent the ends of said stator.

2. A dynamoelectric machine as defined in claim 1 in which said outward edge of each said baffle is straight.

3. A dynamoelectric machine as defined in claim 1 in which said radially outward edge of each said baffle is curved generally to follow said periphery of rotation.

4. A dynamoelectric machine as defined in any of claims 1, 2 or 3 in which said inward edge of each said baffle is straight.

5. A salient pole rotor for a dynamoelectric machine having no ventilation fan associated therewith, comprising

a shaft having a longitudinal axis,

a plurality of poles mounted on said shaft and extending axially, each said pole having a pole tip at a distance from said longitudinal axis, said pole tips defining a periphery of rotation,

a winding on each said pole, each said pole and said winding thereon forming a pole member, adjacent ones of said pole members defining therebetween an interpolar space, and

a generally wedge-shaped baffle for improving air flow in the machine at each end of each said interpolar space, each said baffle extending between adjacent pole members across the interpolar space and having a radially outward edge adjacent said periphery of rotation and an inward edge spaced radially outward from a bottom of the shaft.

6. A salient pole rotor as defined in claim 5 in which said inward edge of each said baffle has an axially extending curve forming a bell mouth configuration.