Multiple natural frequency coupling apparatus

1. A multiple natural frequency coupling apparatus for rotatably connecting a rotatable driving member to a rotatable driven member of a drive line, comprising:

a substantially cylindrical housing having a longitudinal axis;

a substantially cylindrical rigid outer shaft coaxially aligned with said longitudinal axis and connected to said housing;

a substantially cylindrical inner shaft coaxially aligned with said longitudinal axis and having a torsional stiffness about said longitudinal axis different than said outer shaft;

a substantially cylindrical fluid chuck housing coaxially aligned with said longitudinal axis and connected to said inner shaft; and

a substantially cylindrical collapsible sleeve coaxially aligned with said longitudinal axis and disposed between said fluid chuck housing and said outer shaft, wherein said collapsible sleeve may move between a non-actuated position, wherein said collapsible sleeve does not engage said outer shaft thereby providing a first torsional stiffness of said coupling apparatus corresponding to a first natural frequency when said inner shaft is rotatably driven, and an actuated position, wherein said collapsible sleeve engages said outer shaft thereby providing a second torsional stiffness of said coupling apparatus corresponding to a second natural frequency when said outer shaft is rotatably driven.

2. The coupling apparatus as stated in claim 1 , further comprising:

a substantially cylindrical bearing coaxially aligned with said longitudinal axis and located between said housing and said fluid chuck housing for rotatably supporting said fluid chuck housing, wherein said bearing is connected to said housing.

3. The coupling apparatus as stated in claim 1 , further comprising:

a substantially cylindrical mounting disk coaxially aligned with said longitudinal axis and connected to said housing and said inner shaft, wherein said mounting disk is connectable to said driven member.

4. The coupling apparatus as stated in claim 1 , further comprising:

said fluid chuck housing connectable to said driving member.

5. The coupling apparatus as stated in claim 1 , further comprising:

a dampener coaxially aligned with said longitudinal axis and connected to said fluid chuck housing.

6. The coupling apparatus as stated in claim 5 , further comprising:

said dampener connectable to said driving member.

7. The coupling apparatus as stated in claim 5 , wherein said dampener further comprises:

a substantially cylindrical flange coaxially aligned with said longitudinal axis and connected to said fluid chuck housing;

a substantially cylindrical torsionally compliant coupling element coaxially aligned with said longitudinal axis and connected to said flange; and

said flange connectable to said driving member.

8. The coupling apparatus as stated in claim 1 , further comprising:

a dampener coaxially aligned with said longitudinal axis and connected to said inner shaft and said housing.

9. The coupling apparatus as stated in claim 8 , further comprising:

a substantially cylindrical mounting disk coaxially aligned with said longitudinal axis and connected to said dampener, wherein said mounting disk is connectable to said driven member.

10. The coupling apparatus as stated in claim 8 , wherein said dampener further comprises:

a substantially cylindrical flange coaxially aligned with said longitudinal axis and connected to said inner shaft and said housing;

a substantially cylindrical torsionally compliant coupling element coaxially aligned with said longitudinal axis and connected to said flange; and

a substantially cylindrical mounting disk coaxially aligned with said longitudinal axis and connected to said flange and said housing, wherein said mounting disk is connectable to said driven member.

11. The coupling apparatus as stated in claim 1 , further comprising:

said outer shaft having a torsional stiffness greater than said inner shaft.

12. A multiple natural frequency coupling apparatus for rotatably connecting a rotatable driving member to a rotatable driven member of a drive line, comprising:

a substantially cylindrical housing having a longitudinal axis;

a substantially cylindrical rigid outer shaft coaxially aligned with said longitudinal axis and connected to said housing;

a substantially cylindrical inner shaft coaxially aligned with said longitudinal axis and having a torsional stiffness about said longitudinal axis different than said outer shaft;

a substantially cylindrical fluid chuck housing coaxially aligned with said longitudinal axis and connected to said inner shaft;

a substantially cylindrical collapsible sleeve coaxially aligned with said longitudinal axis and disposed between said fluid chuck housing and said outer shaft, wherein said collapsible sleeve may move between a non-actuated position, wherein said collapsible sleeve does not engage said outer shaft thereby providing a first torsional stiffness of said coupling apparatus corresponding to a first natural frequency when said inner shaft is rotatably driven, and an actuated position, wherein said collapsible sleeve engages said outer shaft thereby providing a second torsional stiffness of said coupling apparatus corresponding to a second natural frequency when said outer shaft is rotatably driven; and

said fluid chuck housing having an annular recess for housing said collapsible sleeve and having a passageway in communication with said recess and communicable with a pressurized fluid source for communicating pressurized fluid to and from said recess.

13. The coupling apparatus as stated in claim 12 , further comprising:

said collapsible sleeve moveable to said actuated position when said recess and said passageway in said fluid chuck housing are pressurized with said pressurized fluid, and said collapsible sleeve moveable to said non-actuated position when said recess and said passageway are not pressurized with said pressurized fluid.

14. A multiple natural frequency coupling apparatus for connecting a rotatable driving member to a rotatable driven member of a drive line, comprising:

a substantially cylindrical housing having a longitudinal axis;

a substantially cylindrical outer shaft coaxially aligned with and connected to said housing and having a first torsional stiffness;

a substantially cylindrical inner shaft coaxially aligned with said housing and said outer shaft, and said inner shaft having a second torsional stiffness;

a substantially cylindrical fluid chuck housing coaxially aligned with and connected to said inner shaft, and said fluid chuck housing having a passageway in communication with a pressurized fluid source for communicating pressurized fluid to a recess formed between said fluid chuck housing and said outer shaft; and

a substantially cylindrical collapsible sleeve coaxially aligned with said outer shaft and said fluid chuck housing and disposed within said recess, wherein said collapsible sleeve may move between a non-actuated position, wherein said recess is not pressurized with pressurized fluid thereby not engaging said collapsible sleeve with said outer shaft and providing a first torsional stiffness of said coupling apparatus corresponding to a first natural frequency, and an actuated position, wherein said recess is pressurized with pressurized fluid thereby engaging said collapsible sleeve with said outer shaft and providing a second torsional stiffness of said coupling apparatus corresponding to a second natural frequency.

15. The coupling apparatus as stated in claim 14 , further comprising:

a substantially cylindrical sleeve bearing connected to said housing and coaxially aligned with and located between said housing and said fluid chuck housing for rotatably supporting said fluid chuck housing.

16. The coupling apparatus as stated in claim 14 , further comprising:

a substantially cylindrical mounting disk coaxially aligned with and connected to said housing, wherein said mounting disk is connectable to said driven member.

17. The coupling apparatus as stated in claim 14 , further comprising:

a substantially cylindrical dampener coaxially aligned with and connected to said housing and said inner shaft; and

a substantially cylindrical mounting disk coaxially aligned with and connected to said dampener, wherein said mounting disk is connectable to said driven member.

18. The coupling apparatus as stated in claim 14 , further comprising:

a substantially cylindrical dampener coaxially aligned with and connected to said fluid chuck housing, wherein said dampener is connectable to said driving member.

19. The coupling apparatus as stated in claim 14 , further comprising:

said fluid chuck housing connectable to said driving member.