Dynamoelectric machine stator mounting means and method of making same

A stator support structure comprising a housing having a plurality of ribs arranged to define a bore for receiving a stator therein, each of at least two of said ribs having areas of high radial rigidity and separate areas of lower radial rigidity thereon, the areas of lowest radial rigidity on said ribs being spaced a substantial arcuate distance from the areas of highest radial rigidity on the ribs;

• and a plurality of stress relief means mounted, respectively, at predetermined spaced points on said at least two ribs adjacent their areas of highest radial rigidity, each of said stress relief means being effective to apply a predetermined compressive force to a stator responsive to the stator being mounted for operation within said bore, said predetermined compressive force applied by each of said stress relief means being effective, in combination with other radial compressive forces applied to the stator from the areas of lowest radial rigidity of said ribs to support the stator in a preselected geometric configuration within a narrow range of tolerances;
• each of said stress relief means comprising a pair of bars, each positioned, respectively, on opposite sides of a rib and including mounting means for mounting opposite ends of each bar in relatively fixed relation to the rib on which it is mounted while positioning a central portion of the bar in spaced relation to said rib to transmit said predetermined force to a stator;
• each of said ribs having a radially innermost surface that conforms generally in configuration to the radially outermost surface of a stator adapted to be positioned within said bore, except for a plurality of recesses defined in each of said innermost surfaces adjacent the central portion of each of said bars, each of said mounting means being effective to mount one of the opposite ends of a respective one of said bars in relatively fixed relation to the rib, thereby to place said opposite ends, respectively, on opposite sides of one of said recesses;
• the central portion of each of said bars being positioned generally parallel to a side of the rib on which it is mounted, and being free to be deflected radially outward a predetermined distance without moving into abutting engagement with said rib, responsive to a compressive force being transmitted from the bar to a stator positioned in said bore;
• each of said mounting means comprising a pair of fulcrum supports that, respectively, engage said bars adjacent to opposite ends thereof and are effective to support said opposite ends for rotational movement around the fulcrum supports responsive to said compressive force being applied to the central portions of the bars to deflect them radially outward;
• each pair of fulcrum supports comprising a pair of pins mounted, respectively, in fixed position on their associated rib and disposed to project from a side thereof in a direction generally transverse to the direction of said radial deflection of the bar mounted thereon;
• apertures through the ribs adjacent opposite sides of the respective recesses for receiving one of said pins, respectively, through each of said apertures, each pin being disposed in a respective aperture to project outward from opposite sides of the rib;
• each of said pins being secured in position relative to the bars supported thereon to effectively limit movement of the bars in the axial direction of the pins while enabling the bars to pivot around the longitudinal axis of each of the respective pins;
• each of said pins being free to rotate in the aperture through the rib in which it is mounted.

A stator and stator support structure assembly comprising:

• a housing having a plurality of axially spaced ribs having inner edge portions defining a bore, each of at least two of said ribs having areas of high radial rigidity in an outward direction and separate areas of lower radial rigidity in an outward direction, the areas of lower rigidity being spaced a substantial arcuate distance from the areas of high rigidity;
• a stator including a magnetic core being received in the bore and a plurality of support members disposed at arcuately spaced points around the outer periphery of the core;
• a first group of said support members being compressed between said core and areas of said ribs having lower radial rigidity;
• a plurality of stress relief means mounted, respectively, at predetermined spaced points on said two ribs adjacent their areas of high radial rigidity for applying predetermined respective compressive forces to a second group of said support members compressed between said stress relief means and said core, the compressive force applied by each of said stress relief means on said second group of support elements being substantially equal to respective compressive forces exerted on said first group of support elements by the areas of lower radial rigidity of the same rib.

A stator and stator support structure assembly comprising:

• a housing having a plurality of axially spaced ribs having inner edge portions defining a bore, each of at least two of said ribs having areas of high radial rigidity in an outward direction and separate areas of lower radial rigidity in an outward direction, the areas of lower rigidity being spaced a substantial arcuate distance from the areas of high rigidity;
• a stator including a magnetic core received in the bore;
• said ribs applying compressive forces on said stator in the areas of said ribs of lower radial rigidity;
• and a plurality of stress-relief means mounted, respectively, at predetermined spaced points on said two ribs adjacent their areas of high radial rigidity for applying predetermined respective compressive forces to said stator at positions arcuately spaced from the positions at which the areas of lower rigidity apply compressive forces on said stator, the compressive force applied by each of said stress relief means being substantially equal to the compressive force applied by each of the areas of lower rigidity for the same rib.

A stator and stator support structure assembly comprising a housing having a plurality of ribs arranged to define a bore for receiving a stator therein, each of at least two of said ribs having areas of high radial rigidity and separate areas of lower radial rigidity thereon, the areas of lowest radial rigidity being spaced a substantial arcuate distance from the areas of highest radial rigidity, a stator comprising a magnetic core and a plurality of core support members disposed at arcuately spaced points around the outer periphery of the core, each of said core support members being compressed between the core and said ribs with a first group of said core support members positioned adjacent said areas of high radial rigidity and a second group of said core support members positioned adjacent said areas of lower radial rigidity of the housing ribs, and a plurality of stress-relief means mounted at predetermined spaced points on said at least two ribs adjacent their areas of high radial rigidity thereby to enable each stress relief means to apply a predetermined compressive force to one of the core support members in said first group and to prevent the stator core or core support members from engaging the areas of high radially rigidity of said ribs, each of the core support members in said second group being arranged to engage said at least two ribs adjacent a respective one of said areas of lower radial rigidity thereof, the compressive force transmitted from each of said stress-relief means to a juxtaposed core support member in the first group being about equal to that transmitted from said ribs in the areas of lower radial rigidity thereof to a juxtaposed core support member in the second group, whereby the compressive forces transmitted to each of the core support members in said first and second groups is substantially equal and is effective in combination to support the stator in a predetermined geometric configuration.