FLUID-COOLED DYNAMOMETER

• US 3,863,083 A
• Filed: 06/13/1973
• Issued: 01/28/1975
• Est. Priority Date: 06/13/1973
• Status: Expired due to Term

• Current Assignee: Ralph L. Jaeschke
• Original Assignee: Ralph L. Jaeschke
• Inventors: Jaeschke, Ralph L.
• Primary Examiner(s): Miller, J. D.
• Assistant Examiner(s): Salce, Patrick R.
• Application Number:
  US05/369,669
• Time in Patent Office: 594 Days
• Field of Search: 310/105,52,54,58,59,60,64
• US Class Current: 310/52
• CPC Class Codes: G01L 3/22 electrically or magnetically actuated
• CPC Class Codes: H02K 49/043 with a radial airgap
• CPC Class Codes: H02K 9/197 in which the rotor or stator space is fluid-tight, e.g. to provide for different cooling media for rotor and stator

Abstract

A dynamometer is effectively cooled by passing a cooling fluid through uniquely structured parts of the dynamometer. These parts include an integrally formed combination inductor and housing to which the field coil is directly mounted. The field coil is mounted within a central annular opening extending inside of the housing. The inside of the housing has formed therein a number of circumferential grooves on each side of the annular groove of the coil joined by passageways which allow the cooling fluid to pass between the circumferential grooves and out the housing ends. The cooling fluid passes from the annular field coil groove to the inside of the housing enclosure wherein the cooling fluid is confined within a magnetic gap defined between a rotor assembly and the housing. The rotation of the rotor assembly causes the cooling fluid to be centrifugally distributed along the magnetic gap, into the circumferential grooves and out the housing to thereby dissipate the eddy-current generated heat in the dynamometer.

Claims

1. A fluid cooled eddy-current apparatus comprising:

a housing enclosure having a longitudinal portion and end portions substantially perpendicular to said longitudinal portion cooperating to define a chamber;

an input shaft;

a rotor located in said chamber of said housing;

inductor means forming said longitudinal portion of said housing to define a first longitudinal inner surface enclosing said rotor and a second external longitudinal surface forming the outside surface of said housing;

a field coil mounted proximately to said inductor means And said rotor for magnetically coupling said rotor and said longitudinal portion of said housing; and

said inductor means forming a fluid inlet and fluid passage means, said fluid passage means being formed in said first inner surface of said inductor means to extend substantially perpendicularly to said inductor means from said first inner surface proximate to said rotor into said inductor means.

2. A fluid cooled eddy-current apparatus as defined by claim 1 wherein the fluid passage means formed in said first inner surface is formed to define a plurality of substantially parallel circumferential grooves extending into said inductor means, said inductor means further forming a passageway extending through said circumferential grooves to provide fluid communication between said grooves by way of said inductor means.

3. A fluid cooled eddy-current apparatus as defined by claim 1 wherein said end portions of said housing have a fluid outlet formed therein as an annular ring.

4. A fluid cooled eddy-current apparatus comprising:

a shaft being adapted for connection to a motor at one end of said shaft;

a rotor connected to said shaft to rotate in response to a rotation of said shaft by said motor;

a pole member assembly mounted along the peripheral surface of said rotor to rotate with said rotor;

a housing enclosure of inductor material, having an inner surface spacedly extending longitudinally around said pole member assembly of said rotor to provide a magnetic gap between said inner surface of said housing and said pole member assembly;

a field coil mounted to said housing to electromagnetically couple said housing and said pole member assembly;

cover means for enclosing the ends of said housing to allow said shaft to extend from said housing enclosure; and

said housing forming at least a pair of circumferential grooves extending substantially normally into the body of said housing from said inner surface of said housing, said housing further forming a lateral passageway extending from one end of said housing and through said circumferential grooves.

5. A fluid cooled eddy-current apparatus as set forth in claim 2 wherein said housing has at least one passageway extending longitudinally into said housing to connect the circumferential grooves formed in said housing and allow fluid communication between the pair of circumferential grooves through said passage.

6. A fluid cooled eddy-current apparatus as set forth in claim 5 wherein said housing is formed to have an annular opening circumferentially extending from the inner surface of said housing, said field coil being mounted within the annular opening formed in said housing.

7. A fluid cooled eddy-current apparatus as set forth in claim 6 including a cover ring extending along the pole member side of the annular opening in said housing to enclose said field coil in the annular opening thereby, said cover ring having an orifice passageway to allow fluid communication between the annular opening and the space between said housing and said pole members.

8. A fluid cooled eddy-current apparatus as set forth in claim 7 wherein the cooling fluid is water, and including a waterproof jacket for enclosing said field coil therein.

9. A fluid cooled eddy-current apparatus as set forth in claim 7 wherein said cover means includes a pair of end plates, each end plate having an outlet and a collector groove for communicating the fluid from the space between said housing and said pole members to the outlet. 4

10. A fluid cooled eddy-current apparatus as set forth in claim 9 wherein said housing forms at least a pair of grooves at each end of said housing with at least one passageway extending longitudinally into said housing from each end of said housing to connect each of the pair of grooves and allow fluid communication between the pair of grooves and the collector groove in said end plate nearest the pair of grooves.

11. A fluid cooled eddy-current apparatus as set forth in claim 10 wherein said housing has formed therein at each end of said housing three passageways spaced along the circumference of said housing to connect the pair of grooves formed at each end of said housing.

12. A fluid cooled eddy-current apparatus as set forth in claim 11 wherein said housing acts as the stator of said eddy-current apparatus and said housing is formed of a suitable stator material having an electrical resistivity substantially in the range of 15 to 25 micro-ohm-centimeter.

13. A fluid cooled dynamometer assembly for testing motor torque comprising:

a rotor assembly connectable to the tested motor to rotate with any rotation of the tested motor;

a housing having an enclosing side extending around said rotor assembly and having an annular chamber formed therein;

a field coil mounted in the annular chamber of said housing to electromagnetically couple said rotor assembly and said housing;

said housing having a series of circumferential grooves formed in the enclosing side of said housing with said grooves being connected by a passageway to allow the cooling fluid to be communicated along the enclosing side of said housing; and

said series of circumferential grooves formed in the enclosing side of said housing providing an increased area to the cooling fluid with said passageway extending through an end of said housing to allow the cooling fluid entering said circumferential grooves to be exhausted from the end of said housing.

14. A fluid-cooled dynamometer assembly comprising:

an input shaft;

a rotor assembly connected to said input shaft to rotate therewith;

an elongate housing composed of a material having an electrical resistivity substantially in the range of 15 to 25 micro-ohms per centimeter and having an internal surface therein which defines an annular chamber;

said rotor assembly being located in said annular chamber and being spaced from said internal surface of said elongate housing by a magnetic gap;

an annular field coil having an energized condition for electromagnetically coupling said rotor assembly to said housing so that rotation of said rotor assembly causes a rotation of said housing;

a fluid inlet for directing fluid flow through said annular chamber of said housing to effect cooling of said rotor assembly and said housing; and

a fluid outlet for directing fluid flow from said annular chamber.

15. A fluid-cooled dynamometer assembly as set forth in claim 14 wherein said field coil when energized establishes a flux path extending from said field coil to said housing and therefrom across said magnetic gap to said rotor assembly.

16. A fluid cooled eddy-current apparatus comprising:

a shaft being adapted for connection to a motor at one end of said shaft;

a rotor connected to said shaft to rotate in response to a rotation of said shaft by said motor;

a pole member assembly mounted along the peripheral surface of said rotor to rotate with said rotor;

a housing enclosure of inductor material, having an inner surface spacedly extending longitudinally around said pole member assembly of said rotor to provide a magnetic gap between said inner surface of said housing and said pole member assembly;

a field coil mounted to said housing to electromagnetically couple said housing and said pole member assembly;

cover means for enclosing the ends of said housing to allow said shaft to extend from said housing enclosure;

said housing forming at least a pair of circumferential grooves extending substantially normally into the body of said housing from said inner surface of said housing, said housing also having at least one passageway extending longitudinally into said housing to connect the circumferential grooves formed in said housing and allowing fluid communication between the pair of circumferential grooves through said passageway, said housing also being formed to have an annular openinG circumferentially extending from the inner surface of said housing, said field coil being mounted within the annular opening formed in said housing, and said housing also having an inlet formed to extend into the annular opening of said housing and an outlet formed in said cover means, said inlet and said outlet establishing a fluid flow path from the inlet to the annular opening, therefrom to the space between said housing and said pole members, therefrom partially into the circumferential grooves, and from the grooves to the passageway and into the outlet.