Dual drive continuously variable transmission

• US 20030153426A1
• Filed: 10/25/2002
• Published: 08/14/2003
• Est. Priority Date: 09/14/1998
• Status: Active Grant

• Current Assignee: Albert W. Brown
• Original Assignee: Albert W. Brown
• Inventors: Brown, Albert W.
• Granted Patent: US 6,926,632 B2
• Time in Patent Office: Days
• US Class Current: 475/210
• CPC Class Codes: F16H 2009/163 Arrangements of two or more belt gearings mounted in parallel, e.g. for increasing transmittable torque
• CPC Class Codes: F16H 2061/66295 characterised by means for controlling the geometrical interrelationship of pulleys and the endless flexible member, e.g. belt alignment or position of the resulting axial pulley force in the plane perpendicular to the pulley axis
• CPC Class Codes: F16H 37/08 with differential gearing
• CPC Class Codes: F16H 37/0846 CVT using endless flexible members
• CPC Class Codes: F16H 55/56 of which the bearing parts are relatively axially adjustable
• CPC Class Codes: F16H 9/16 using two pulleys, both built-up out of adjustable conical parts

Abstract

A continuously variable transmission has a first shaft supporting two first pulleys. The two first pulleys each comprise a fixed disk portion and a moveable disk portion whereby axial movement of the moveable disk portions along the first shaft relative to the fixed disk portions changes an effective diameter of the two first pulleys. An articulating mechanism connects the moveable disk portions. The articulating mechanism has a body that is connected to the moveable disk portions. A second shaft extends generally parallel to the first shaft. Two second pulleys are journaled about the second shaft. The two second pulleys each has a fixed disk portion and a moveable disk portion. The two fixed disk portions are rotationally connected to the second shaft through a differential. A pair of belts connect the two second pulleys to the two first pulleys

Claims

1. A continuously variable transmission comprising:

a first shaft supporting two first pulleys, said two first pulleys each comprising a fixed disk portion and a moveable disk portion whereby axial movement of said moveable disk portions along said first shaft relative to said fixed disk portions changes an effective diameter of said two first pulleys, said moveable disk portions of said two first pulleys being interposed along said first shaft between said fixed disk portions of said two first pulleys, an articulating mechanism connecting said moveable disk portions, said articulating mechanism comprising a body that is connected to said moveable disk portions;

a second shaft extending generally parallel to said first shaft, two second pulleys being journaled on said second shaft, said two second pulleys each comprising a fixed disk portion and a moveable disk portion, said two fixed disk portions being rotationally connected to said second shaft through a differential; and

a pair of belts connecting said two second pulleys to said two first pulleys.

2. The transmission of claim 1, wherein said belts have a width of about 24 mm.

3. The transmission of claim 1, wherein said belts have a width of about 30 mm.

4. The transmission of claim 1, wherein said first shaft is a drive shaft and said second shaft is a driven shaft

5. The transmission of claim 1, wherein said first shaft is a driven shaft and said second shaft is a drive shaft

6. The transmission of claim 5, wherein said drive shaft is adapted for slight axial displacement.

7. The transmission of claim 1, wherein said differential comprises a pair of bevel gears, said bevel gears being integrally formed with said fixed disk portions of said second pulleys.

8. The transmission of claim 1, wherein said differential comprises at least one spider gear that is mounted on a shaft that extends generally normal to said second shaft and that is integrally formed with said second shaft

9. The transmission of claim 8, wherein said differential comprises three spider gears and three respective shafts.

10. The transmission of claim 8, wherein said differential comprises four spider gears and four respective shafts.

11. The transmission of claim 1, wherein at least one of said second pulleys comprises a double acting cylinder assembly.

12. The transmission of claim 11, wherein said double acting cylinder assembly comprises two disc shaped pistons that are axially spaced from each other.

13. The transmission of claim 1, wherein an output of said transmission powers a power takeoff and reduction gear.

14. The transmission of claim 1, wherein each of said first pulleys further comprise a cylinder that defines a chamber and a piston that is disposed within said chamber and that is secured to movable disk portion with at least one snap ring, said at least one snap ring being secured with a spiral retaining ring.

15. The transmission of claim 1, wherein said body of said articulating mechanism is secured to each of said movable disk portions with a toggle member.

17. The transmission of claim 1, wherein said first shaft and said second shaft each form a flow lumen for hydraulic fluids.

18. The transmission of claim 17, wherein each of said lumens contains a labyrinth seal.

19. The transmission of claim 17, wherein each of said lumens contains a pair of seals that are spaced apart, said seals being configured to hydraulically balance each of said first shaft and said second shaft.

20. The transmission of claim 17, wherein at least one of said lumens contains a biased rod.

21. The transmission of claim 1, wherein said two second pulleys are supported by bearings that are mounted in a cage integrally formed on said second shaft.

22. The transmission of claim 1, wherein said first shaft is journaled by at least one thrust bearing

23. The transmission of claim 22, wherein said first shaft is coupled to an output gearing arrangement, said thrust bearing being arranged to oppose axial forces created by said output gearing arrangement.

24. The transmission of claim 23, wherein said first shaft is journaled by at least one ball bearing.

25. The transmission of claim 24, wherein said ball bearing is cooled by lubricant used to control movement of said first pulleys.

26. The transmission of claim 1, wherein each of said first pulleys further comprise a cylinder that defines a chamber and a piston that is disposed within said chamber, said piston being biased by a crest-to-crest biasing member.

27. The transmission of claim 26, said second shaft forms a flow lumen for hydraulic fluids, said lumen communicating with each of said second pulleys through a communication passage, a pair of seals being disposed to each side of said communication passage at a radial location between second pulleys and said second shaft.

28. The transmission of claim 1, wherein a balance dam is positioned within each of said first pulleys.

29. The transmission of claim 1, wherein each of said first pulleys further comprise a cylinder that defines a chamber and a piston that is disposed within said chamber, said cylinder having a conical portion that tapers in a direction away from said belts.

30. The transmission of claim 1 further comprising a housing that encases said first pulleys, said second pulleys and said belts, each of said first pulleys further comprising a cylinder that defines a chamber and a piston that is disposed within said chamber, said housing comprising a pair of lips that extend inward toward said belts and one of said pair of lips extending inside each of said chambers defined by said cylinder.

16. The transmission of claim 16, wherein said toggle member is secured to said moveable disk portion with a threaded fastener.

31. A continuously variable transmission comprising:

a first shaft supporting two first pulleys, said two first pulleys each comprising a fixed disk portion and a moveable disk portion whereby axial movement of said moveable disk portions along said first shaft relative to said fixed disk portions changes an effective diameter of said two first pulleys, an articulating mechanism connecting said moveable disk portions such that the effective diameters of said two first pulleys are maintained substantially equal by said articulating mechanism,

a second shaft extending generally parallel to said first shaft, two second pulleys being journaled on said second shaft, said two second pulleys each comprising a fixed disk portion and a moveable disk portion whereby axial movement of said moveable disk portions along said second shaft relative to said fixed disk portions changes an effective diameter of said two second pulleys, said two fixed disk portions being rotationally connected to said second shaft by a differential;

a pair of belts connecting said two second pulleys to said two first pulleys and said two first pulleys and said two second pulleys being hydraulically actuated.

32. The transmission of claim 31, wherein said first shaft is a drive shaft and said second shaft is a driven shaft

33. The transmission of claim 31, wherein said first shaft is a driven shaft and said second shaft is a drive shaft

34. The transmission of claim 31, wherein said differential comprises at least one spider gear that is mounted on a shaft that extends generally normal to said second shaft and that is integrally formed with said second shaft

35. The transmission of claim 31, wherein an output of said transmission powers a power takeoff and reduction gear.

36. The transmission of claim 31, wherein an output of said transmission powers a four wheel drive vehicle.

37. The transmission of claim 31, wherein an input of said transmission receives power from a torque converter/engine combination.

38. The transmission of claim 31, wherein said body of said articulating mechanism is secured to each of said movable disk portions with a toggle member.

39. The transmission of claim 38, wherein said toggle member is secured to said moveable disk portion with a threaded fastener.

40. The transmission of claim 31, wherein said first shaft and said second shaft each form a flow lumen for hydraulic fluids.

41. The transmission of claim 40, wherein fluid from said lumens are directed to bearings for lubrication.

42. The transmission of claim 31, wherein each of said first pulleys further comprise a cylinder that defines a chamber and a piston that is disposed within said chamber, said piston being biased by a crest-to-crest biasing member.

43. The transmission of claim 31, wherein a balance dam is positioned within each of said first pulleys.

44. The transmission of claim 31, wherein each of said first pulleys further comprise a cylinder that defines a chamber and a piston that is disposed within said chamber, said cylinder having a conical portion that tapers in a direction away from said belts.

45. The transmission of claim 44, wherein said belts are interposed between said tapering conical portions.