Continuously variable transmission

• US 8,262,536 B2
• Filed: 06/11/2008
• Issued: 09/11/2012
• Est. Priority Date: 12/09/2005
• Status: Expired due to Fees

• Current Assignee: Enviolo BV
• Original Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Inventors: Nichols, Jon M, Pohl, Brad P, Dawe, Daniel J, Armstrong, Oronde J, Lohr, Charles B, McDaniel, Loren T, Simister, Matthew P, Thomassy, Fernand A, Usmani, Ghayyurul I, Elhardt, Paul M, Stewart, Terry L, Poxton, Peter D, Eidson, Elton L
• Primary Examiner(s): Joyce, William C
• Application Number:
  US12/137,456
• Publication Number:
  US 20080261771A1
• Time in Patent Office: 1,553 Days
• Field of Search: 476 36- 38, 476/43, 476/50, 744/731.3, 744/731.4
• US Class Current: 476/38
• CPC Class Codes: F16H 15/28 with external friction surface
• CPC Class Codes: F16H 15/52 in which a member of uniform effective diameter mounted on a shaft may co-operate with different parts of another member
• CPC Class Codes: F16H 57/02 Gearboxes; Mounting gearing therein
• CPC Class Codes: F16H 57/043 within rotary parts, e.g. axial channels or radial openings in shafts
• CPC Class Codes: F16H 57/0487 Friction gearings
• CPC Class Codes: F16H 61/6649 characterised by the means for controlling the torque transmitting capability of the gearing
• CPC Class Codes: F16H 63/067 mechanical actuating means
• CPC Class Codes: Y10T 74/18304 Axial cam
• CPC Class Codes: Y10T 74/19921 Separate rim
• CPC Class Codes: Y10T 74/2186 Gear casings

Abstract

Inventive embodiments are directed to components, subassemblies, systems, and/or methods for continuously variable transmissions (CVT). In one embodiment, a main axle is adapted to receive a shift rod that cooperates with a shift rod nut to actuate a ratio change in a CVT. In another embodiment, an axial force generating mechanism can include a torsion spring, a traction ring adapted to receive the torsion spring, and a roller cage retainer configured to cooperate with the traction ring to house the torsion spring. Various inventive idler-and-shift-cam assemblies can be used to facilitate shifting the ratio of a CVT. Embodiments of a hub shell and a hub cover are adapted to house components of a CVT and, in some embodiments, to cooperate with other components of the CVT to support operation and/or functionality of the CVT. Among other things, shift control interfaces and braking features for a CVT are disclosed.

Claims

1. A continuously variable transmission (CVT) comprising:

a first traction ring;

a second traction ring;

a plurality of power rollers interposed between and in contact with the first and second traction rings, wherein the power rollers are configured to rotate about a tiltable axis;

an idler in contact with each of the power rollers, the idler located radially inward of the point of contact between the power rollers and the first and second traction rings;

a shift rod nut operationally coupled to the power rollers;

a shift rod coupled to the shift rod nut, wherein the shift rod and shift rod nut are configured such that a rotation of the shift rod causes the shift rod nut to translate axially and to operably actuate a tilt in said tiltable axis; and

a main axle having first end and a second end and a central bore, the main axle having a slot located between the first end and the second end, the slot configured to receive the shift rod nut.

2. The CVT of claim 1, further comprising at least one shift cam operably coupled to the power rollers, and wherein the shift rod nut is adapted to actuate said shift cam.

3. The CVT of claim 1, further comprising an idler bushing, wherein the shift rod nut is adapted to actuate said idler bushing.

4. The CVT of claim 3, further comprising at least one shift cam, wherein said idler bushing is adapted to actuate said shift cam.

5. The CVT of claim 4, further comprising at least one leg adapted to operably couple to the power rollers and to actuate said tilt, wherein said shift cam is operationally coupled to said leg.