Flexible coupling with radially offset beams formed by asymmetric slot pairs

1. A flexible coupling for flexibly joining two shafts, the flexible coupling comprising:

a unitary solid cylindrical body having a first end, a second end, and therebetween having one or more longitudinally spaced circular disks spaced by asymmetric slot pairs;

a radially offset beam, having a minimum beam thickness (T 1 ) and a longitudinal beam length (L 1 ), formed between a first slot and a second slot of each asymmetric slot pair, such that the radially offset beam is parallel to a diameter of the cylindrical body and is offset from the parallel diameter by a radial beam offset distance (R 1 );

each beam being rotationally offset from longitudinally adjacent beams; and

means at the first end for coaxially connecting the first end to a first one of the two shafts, and means at the second end for coaxially connecting the second end to a second one of the two shafts.

2. The flexible coupling of claim 1 , wherein:

the radial beam offset distance (R 1 ) is approximately equal to the largest of a radius (R 2 ) of a coaxial shaft hole of the means at the first end or at the second end.

3. The flexible coupling of claim 1 , wherein:

a rotational offset angle between longitudinally adjacent beams has the same magnitude for all pairs of longitudinally adjacent beams; and

the rotational offset angle has a magnitude that divides into 360 degrees an integer number N times.

4. The flexible coupling of claim 3 , wherein:

the quantity of beams is an integer multiple of the number N.

5. The flexible coupling of claim 3 , wherein:

the rotational offset angle increments in the same rotational direction from each beam to each beam's next longitudinally adjacent beam progressing from a first beam at the first end to a last beam at the second end.

6. The flexible coupling of claim 1 , wherein:

all of the disks have a same nominal disk length (L 3 ); and

all of the first slots and all of the second slots have a same nominal slot length (L 2 ,L 4 ).

7. The flexible coupling of claim 6 , wherein:

the nominal disk length (L 3 ) is equal to the nominal slot length (L 2 ).

8. The flexible coupling of claim 6 , wherein:

the nominal disk length (L 3 ) is equal to a minimum value of the beam length (L 1 ).

9. The flexible coupling of claim 1 , wherein:

the beam length (L 1 ) has a constant value for the entire beam.

10. The flexible coupling of claim 1 , wherein:

each beam has a beam thickness that is uniformly equal to the minimum beam thickness (T 1 ) throughout a longitudinal length between adjacent disks.

11. The flexible coupling of claim 1 , wherein:

each beam has a beam thickness that varies along a longitudinal length between adjacent disks, such that the minimum beam thickness (T 1 ) occurs in the approximate center of the longitudinal length, and the beam thickness increases from the minimum thickness (T 1 ) to a maximum where the beam joins a disk, with the increase being determined by rounded bottoms on the first slot and on the second slot of the asymmetric slot pair that formed the beam.

12. The flexible coupling of claim 1 , wherein:

the means for coaxially connecting each of the first and second ends to one of the two shafts comprises hub means.

13. The flexible coupling of claim 1 , wherein:

the means for coaxially connecting each of the first and second ends to one of the two shafts comprises hub means with a shaft hole with at least one set screw.

14. The flexible coupling of claim 1 , wherein:

the means for coaxially connecting each of the first and second ends to one of the two shafts comprises hub means with a shaft hole and at least one clamp.

15. The flexible coupling of claim 1 , wherein:

the two shafts are rotating members having potentially different axes of rotation.

16. The flexible coupling of claim 1 , wherein:

the two shafts are structural members that require flexible joining.

17. A flexible coupling for flexibly joining two shafts, the flexible coupling comprising:

a unitary solid cylindrical body having a first end, a second end, and therebetween having one or more longitudinally spaced circular disks spaced by asymmetric slot pairs;

a radially offset beam, having a minimum beam thickness (T 1 ) and a longitudinal beam length (L 1 ), formed between a first slot and a second slot of each asymmetric slot pair, such that the radially offset beam is parallel to a diameter of the cylindrical body and is offset from the parallel diameter by a radial beam offset distance (R 1 );

each beam being rotationally offset from longitudinally adjacent beams; and

means eat the first end for coaxially connecting the first end to a first one of the two shafts, and means at the second end for coaxially connecting the second end to a second one of the two shafts, and

wherein the sides of the first slots and the sides of the second slots all have a single valued slot slope angle with respect to the plane of a radial slat centerline, wherein the slot slope angle has a value of up to 5 degrees.

18. The flexible coupling of claim 17 , wherein:

the slot slope angle has a value of up to 2 degrees.

19. A method of flexibly joining two shafts with a flexible coupling, comprising the steps of:

making the flexible coupling out of a unitary solid cylindrical body having a first end and a second end;

forming a plurality of radially oriented asymmetric slot pairs longitudinally spaced from the first end to the second end;

forming one or more circular disks longitudinally between asymmetric slot pairs;

forming a radially offset beam between a first slot and a second slot of each asymmetric slot pair, such that the radially offset beam is parallel to a diameter of the cylindrical body and is offset from the parallel diameter by a radial beam offset distance R 1 ;

rotationally offsetting each beam from longitudinally adjacent beams; and

providing means at the first end for coaxially connecting the first end to a first one of the two shafts, and means at the second end for coaxially connecting the second end to a second one of the two shafts.