Flexible coupling sleeve and a flexible shaft coupling incorporating same

• US 7,763,336 B2
• Filed: 05/20/2004
• Issued: 07/27/2010
• Est. Priority Date: 05/20/2004
• Status: Active Grant

• Current Assignee: Gates Corporation (Gates Industrial Corp. Plc)
• Original Assignee: Gates Corporation (Gates Industrial Corp. Plc)
• Inventors: Bell, Richard, Duke, Joseph R. Jr., Wu, William W. L., Clarke, Arthur Jack
• Primary Examiner(s): Chang; Victor S
• Application Number:
  US10/849,716
• Publication Number:
  US 20050260375A1
• Time in Patent Office: 2,259 Days
• Field of Search: 428/36.9, 428/36.91, 428/35.7, 428/36.4, 428/36.8, 464/104, 464/73, 464/903
• US Class Current: 428/36.9
• CPC Class Codes: C08G 18/10 Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/3808 having chlorine atoms
• CPC Class Codes: C08G 18/3821 Carboxylic acids; Esters thereof with monohydroxyl compounds
• CPC Class Codes: C08G 18/4277 Caprolactone and/or substituted caprolactone
• CPC Class Codes: F16D 3/54 Couplings comprising a chain or strip surrounding two wheels arranged side by side and provided with teeth or the equivalent
• CPC Class Codes: F16D 3/725 with an intermediate member made of fibre-reinforced resin made of rubber-like material F16D3/74; shafts made of fibre-reinforced resin F16C3/026
• CPC Class Codes: F16D 3/74 the intermediate member or members being made of rubber or other rubber-like flexible material
• CPC Class Codes: Y10S 464/903 Nonmetal
• CPC Class Codes: Y10T 428/1352 Polymer or resin containing [i.e., natural or synthetic]
• CPC Class Codes: Y10T 428/1372 Randomly noninterengaged or randomly contacting fibers, filaments, particles, or flakes
• CPC Class Codes: Y10T 428/1386 Natural or synthetic rubber or rubber-like compound containing
• CPC Class Codes: Y10T 428/139 Open-ended, self-supporting conduit, cylinder, or tube-type article
• CPC Class Codes: Y10T 428/1393 Multilayer [continuous layer]

Abstract

A flexible shaft coupling sleeve comprising a sleeve shaped body having a central annular portion and a coupling receiving portion at each of two opposing sleeve ends, and a coupling device incorporating such sleeve. The sleeve'"'"'s coupling receiving portions include axially extending teeth on their inner surfaces. The flexible shaft coupling sleeve is formed of a polyurethane elastomer composition.

Claims

1. A coupling sleeve for use in a sleeve-type flexible shaft coupling device having two substantially coaxial end pieces, comprising a generally annular body having an inner periphery and an outer periphery;

said body comprising a central cylindrical portion and two opposing sleeve end portions at either end of said central cylindrical portion of generally cylindrical shape defining respective coupling receiving portions which coaxially mate in rotational driving relation with said end pieces of the coupling device;

said coupling receiving portions each comprising a plurality of circumferentially spaced axially extending teeth arranged along at least a portion of said inner periphery which substantially mesh with complementary grooves in the outer periphery of said end pieces, and characterized in that at least one of said central cylindrical portion and said coupling receiving portions comprises a polyurethane elastomer composition exhibiting thermal stability in the range from about −

35°

C. to at least about 140°

C., and wherein said coupling sleeve possesses an M100 of at least about 1000 psi; and

wherein said coupling sleeve has a ratio of outside diameter to shell thickness of from about 8 to about 11.

2. The coupling sleeve of claim 1 wherein said annular body comprises said polyurethane elastomer composition and said composition provides the primary or sole amount of said coupling sleeve'"'"'s resistance to radial stress.

3. The coupling sleeve of claim 2, wherein said central cylindrical portion comprises said polyurethane elastomer composition and said composition provides the primary or sole amount of said coupling sleeve'"'"'s resistance to circumferential shear stress.

29. The coupling sleeve of claim 1 constructed in the absence of at least one of a tensile member, a fabric jacket and fiber loading of said composition.

30. The coupling sleeve of claim 29 constructed in the absence of both a tensile member and a fabric jacket.

31. The coupling sleeve of claim 1, wherein at least one of said teeth possesses a curvilinear cross-sectional profile.

32. The coupling sleeve of claim 1, wherein said teeth are in alternating arrangement with a plurality of grooves, each of said grooves having a width spanning a portion of the circumference of the sleeve-shaped body inner periphery, and wherein the ratio of the sum of said groove widths to the sum of said tooth widths is less than 0.65:

1.

33. The coupling sleeve of claim 3 wherein the ratio of said sum of said groove widths to said sum of said tooth widths from 0:

50;

1 to 0.10;

1.

34. The coupling sleeve of claim 3 wherein the ratio of said sum of said groove widths to said sum of said tooth widths is from 0.45:

1 to 0.15;

1.

35. The coupling sleeve of claim 1 further comprising a tensile member disposed within said sleeve-shaped body.

36. The coupling sleeve of claim 1 wherein said elastomeric material further comprises from about 1 to about 30 phr of fibers.

37. The coupling sleeve of claim 1 further comprising at least one torque level indicating means on said outer periphery of said sleeve body.

38. The coupling sleeve of claim 37 wherein said torque level indicating means is in the form of graphic elements which form a first pattern on said outer periphery of said sleeve-shaped body at rest, and a second pattern on said outer periphery of said sleeve-shaped body under surface distortion.

45. The coupling sleeve of claim 1 wherein the coupling receiving portions comprise a series of axially extending teeth along the full inner periphery of the sleeve which substantially rigidly engage the full outer periphery of the end pieces.

49. The coupling sleeve of claim 1 wherein the outer periphery of the annular body portion is free of a reinforcing member placed radially outwardly and in close proximity thereto.

50. The coupling sleeve of claim 30 wherein the outer periphery of the annular body portion is free of a reinforcing member placed radially outwardly and in close proximity thereto.

51. The coupling sleeve of claim 1 wherein the respective coupling receiving portions extend respectively from each opposing sleeve end portion axially inwardly along the inner periphery of the sleeve to the central cylindrical portion of the sleeve body.

55. The coupling sleeve of claim 51 wherein said teeth mechanically interlock with said grooves.

4. A coupling sleeve for use in a sleeve-type flexible shaft coupling device having two substantially coaxial end pieces, comprising a generally annular body having an inner periphery and an outer periphery;

said body comprising a central cylindrical portion adapted to resist torsional stress and two opposing sleeve end portions of generally cylindrical shape defining respective coupling receiving portions which coaxially mate in rotational driving relation with said end pieces of the coupling device;

said coupling receiving portions each comprising a plurality of circumferentially spaced axially extending teeth arranged along at least a portion of said inner periphery which substantially mesh with complementary grooves in the outer periphery of said end pieces, and characterized in that at least one of said central cylindrical portion and said coupling receiving portions comprises a polyurethane elastomer wherein said polyurethane elastomer composition possesses urea linkages and comprises the reaction product of,

(a) a polyisocyanate prepolymer composition being prepared by reacting,

(i) a diisocyanate selected from the group consisting of;

(A) aromatic diisocyanates with compact and symmetric structure, and

(B) aliphatic diisocyanates with trans or trans, trans geometric structure,

with;

(ii) a polyol selected from;

(A) polycarbonate polyols,

(B) polyester polyols, and

(C) a mixture of any two or more of said polycarbonate polyols and said polyester polyols,

and;

(b) a chain extender selected from;

(i) symmetric primary diamine chain extenders,

(ii) a mixture of any one or more said symmetric primary diamine chain extenders and a secondary diamine chain extender, and,

(iii) a mixture of any one or more said symmetric primary diamine chain extenders and any one or more said polyols;

and wherein said coupling sleeve has a ratio of outside diameter to shell thickness of from about 8 to about 11.

5. The coupling sleeve of claim 4 wherein said polyurethane elastomer composition possesses an isocyanate to amine or amine/hydroxyl equivalent ratio in the range of from about 0.90:

1 to about 1.40;

1.

6. The coupling sleeve of claim 4 wherein said polyurethane elastomer composition possesses an isocyanate group content of said polyisocyanate prepolymer of from about 2.0% to about 12.0% by weight.

7. The coupling sleeve of claim 6 wherein said polyurethane elastomer composition possesses said isocyanate group content of said polyisocyanate prepolymer in the range of from about 2.5% to about 7.0% by weight.

8. The coupling sleeve of claim 6 wherein said polyurethane elastomer composition wherein said isocyanate group content of said polyisocyanate prepolymer is in the range of from about 3.0% to about 6.0% by weight.

9. The coupling sleeve of claim 4 wherein said polyisocyanate prepolymer composition has an NCO/OH ratio of from about 1.8:

1 to about 2.4;

1.

10. The coupling sleeve of claim 4 wherein said diisocyanate is said aromatic diisocyanate and is selected from the group consisting of;

(a) para-phenylene diisocyanate,

(b) 1,5-naphthalene diisocyanate, and

(c) 2,6-toluene diisocyanate.

11. The coupling sleeve of claim 4 wherein said polyisocyanate prepolymer composition is based on para-phenylene diisocyanate, and has an NCO/OH ratio of about 2:

1.

12. The coupling sleeve of claim 4 wherein said diisocyanate is said aliphatic diisocyanate and is selected from the group consisting of,

(a) trans-1,4-cyclohexane diisocyanate, and

(b) trans,trans-4,4′

-dicyclohexylmethyl diisocyanate.

13. The coupling sleeve of claim 4 wherein said polyisocyanate prepolymer composition is based on trans-1,4-cyclohexane diisocyanate, and has an NCO/OH ratio of about 2.2:

1.

14. The coupling sleeve of claim 4 wherein said polyol contains less than about 0.03% water.

15. The coupling sleeve of claim 4 wherein said polyol is said polycarbonate polyol and has molecular weight of from about 500 to about 5000.

16. The coupling sleeve of claim 4 wherein said polycarbonate polyol is poly(hexamethylene carbonate) diol and has molecular weight of from about 500 to about 5000.

17. The coupling sleeve of claim 4 wherein said poly(hexamethylene carbonate) diol has molecular weight of from about 1500 to about 2500.

18. The coupling sleeve of claim 4 wherein said polyol is said polyester polyol and has molecular weight of from about 500 to about 5000.

19. The coupling sleeve of claim 4 wherein said polyester polyol is polycaprolactone diol and has molecular weights of from about 500 to about 5000.

20. The coupling sleeve of claim 4 wherein said polycaprolactone diol has molecular weights of from about 1500 to about 2500.

21. The coupling sleeve of claim 4 wherein said polyester polyol is poly(hexamethylene adipate) diol and has molecular weight of from about 500 to about 5000.

22. The coupling sleeve of claim 4 wherein said poly(hexamethylene adipate) diol has molecular weight of from about 1500 to about 2500.

23. The coupling sleeve of claim 4 wherein said chain extender is said symmetric primary diamine chain extender and has molecular weight of from about 90 to about 500.

24. The coupling sleeve of claim 4 wherein said symmetric primary diamine chain extender is selected from the group consisting of;

(a) 4,4′

-methylene-bis-(3-chloro-2,6-diethylaniline),

(b) 4,4′

-methylene-bis-(ortho-chloroaniline),

(c) 4,4′

-methylene-bis-(2,3-dichloroaniline),

(d) trimethylene glycol di-para-aminobenzoate,

(e) 4,4′

-methylene-bis(2,6-diethylaniline),

(f) 4,4′

-methylene-bis(2,6-diisopropylaniline),

(g) 4,4′

-methylene-bis(2-methyl-6-isopropylaniline), and

(h) a combination of at least any two of the foregoing symmetric primary diamine chain extenders.

25. The coupling sleeve of claim 4 wherein said chain extender is said mixture of said symmetric primary diamine chain extenders and secondary diamine chain extenders and said secondary diamine chain extenders have molecular weight of from about 150 to about 500.

26. The coupling sleeve of claim 4 wherein said secondary diamine chain extender is selected from the group consisting of;

(a) N,N′

-di-sec-butyl-amino-benzene, and

(b) N,N′

-di-sec-butyl-amino-diphenylmethane.

27. The coupling sleeve of claim 4 wherein said secondary diamine chain extender comprises up to about 25% by weight of said mixture of said symmetric primary diamine chain extenders and said secondary diamine chain extenders.

28. The coupling sleeve of claim 4 wherein said chain extender is said mixture of said symmetric primary diamine chain extenders and said polyols, and said polyols comprise up to about 40% to 50% by weight of said mixture of said symmetric primary diamine chain extenders and said polyols.

42. The coupling sleeve of claim 4 wherein the polyisocyanate prepolymer is characterized by a level of free isocyanate, and the level of free isocyanate in the prepolymer is less than about 1% by weight of the prepolymer.

43. The coupling sleeve of claim 4 wherein the polyisocyanate prepolymer is characterized by a level of free isocyanate, and the level of free isocyanate in the prepolymer is less than about 0.5% by weight of the prepolymer.

46. The coupling sleeve of claim 4 wherein the coupling receiving portions comprise a series of axially extending teeth along the full inner periphery of the sleeve which substantially rigidly engage the full outer periphery of the end pieces.

52. The coupling sleeve of claim 4 wherein the respective coupling receiving portions extend respectively from each opposing sleeve end portion axially inwardly along the inner periphery of the sleeve to the central cylindrical portion of the sleeve body.

56. The coupling sleeve of claim 52 wherein said teeth mechanically interlock with said grooves.

59. The coupling sleeve of claim 4 constructed in the absence of fiber loading, tensile member and fabric jacket and having said composition as its primary constituent.

39. A coupling sleeve for use in a sleeve-type flexible shaft coupling device having two substantially coaxial end pieces, comprising a resilient, generally annular body having an inner periphery and an outer periphery;

said body comprising a central cylindrical portion adapted to resist torsional stress and two opposing sleeve end portions of generally cylindrical shape defining respective coupling receiving portions at either end of said central cylindrical portion which coaxially mate in rotational driving relation with said end pieces of the coupling device;

said coupling receiving portions each comprising a plurality of circumferentially spaced axially extending teeth arranged along at least a portion of said inner periphery which substantially mesh with complementary grooves in the outer periphery of said end pieces, and characterized in that at least one of said central cylindrical portion and said coupling receiving portions comprises a polyurethane elastomer composition, wherein said polyurethane elastomer possesses an M100 of at least about 800 psi; and

wherein said coupling sleeve has a ratio of outside diameter to shell thickness of from about 8 to about 11.

40. The coupling sleeve of claim 39 wherein said polyurethane elastomer possesses an M100 of at least about 900 psi.

41. The coupling sleeve of claim 39 wherein said polyurethane elastomer possesses an M100 in the range of from about 1000 to about 2000 psi.

47. The coupling sleeve of claim 39 wherein the annular body is substantially rigid and the coupling receiving portions comprise a series of axially extending teeth along the full inner periphery of the sleeve which engage the end pieces.

53. The coupling sleeve of claim 39 wherein the respective coupling receiving portions extend respectively from each opposing sleeve end portion axially inwardly along the inner periphery of the sleeve to the central cylindrical portion of the sleeve body.

57. The coupling sleeve of claim 53 wherein said teeth mechanically interlock with said grooves.

44. A coupling sleeve for use in a sleeve-type flexible shaft coupling device with two substantially coaxial end pieces, comprising a generally annular body having an inner periphery and an outer periphery;

said body comprising a central cylindrical portion and two opposing sleeve end portions of generally cylindrical shape defining respective coupling receiving portions which coaxially mate in driving relation with said two end pieces of the coupling device circumferentially around the inner periphery of the sleeve;

said coupling receiving portions each comprising a plurality of circumferentially spaced axially extending teeth arranged along at least a portion of said inner periphery, and characterized in that at least one of said central cylindrical portion and said coupling receiving portions comprises a polyurethane elastomer composition comprising the reaction product of,

(a) a polyisocyanate prepolymer composition being prepared by reacting,

(i) a diisocyanate selected from;

(A) PPDI, and

(B) aliphatic diisocyanates with trans or trans, trans geometric structure,

with;

(ii) a polyol selected from;

(A) polycarbonate polyol,

(B) polycaprolactone polyol, and

(C) a mixture of any two or more of said polycarbonate polyols and said polycaprolactone polyols,

wherein the polyisocyanate prepolymer is characterized by a level of free diisocyanate, and the level of free diisocyanate in the prepolymer is less than about 1% by weight of the prepolymer and;

(b) a symmetric primary diamine chain extender selected from;

(i) MCDEA, and

(ii) TMAB,

(iii) a mixture of any one or more said symmetric primary diamine chain extenders and any one or more said polyols;

wherein said polyurethane elastomer composition possesses an isocyanate to amine equivalent ratio in the range of from about 0.90;

1 to about 1.40;

1, and an isocyanate group content of said polyisocyanate prepolymer of from about 3% to about 6% by weight; and

wherein said coupling sleeve has a ratio of outside diameter to shell thickness of from about 8 to about 11.

48. The coupling sleeve of claim 44 wherein the coupling receiving portions comprise a series of axially extending teeth along the full inner periphery of the sleeve for rigid engagement of the end pieces with the coupling receiving portions along the full inner periphery of the sleeve.

54. The coupling sleeve of claim 44 wherein the respective coupling receiving portions extend respectively from each opposing sleeve end portion axially inwardly along the inner periphery of the sleeve to the central cylindrical portion of the sleeve body.

58. The coupling sleeve of claim 54 wherein said teeth mechanically interlock with said grooves.