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Title:
PLANETARY POWERTRAIN CONFIGURATIONS WITH A BALL VARIATOR CONTINUOUSLY VARIABLE TRANSMISSION USED AS A POWERSPLIT
Document Type and Number:
WIPO Patent Application WO/2017/201355
Kind Code:
A1
Abstract:
Devices and methods are provided herein for the transmission of power in motor vehicles. Power is transmitted in a smoother and more efficient manner by splitting torque into two or more torque paths. A continuously variable transmission is provided with a ball variator assembly having an array of balls, a planetary gear set coupled thereto and an arrangement of rotatable shafts with multiple gears and clutches that extend the ratio range of the variator. In some embodiments, a locking clutch is operably coupled to the planetary gear set to selectively couple two of the elements of the planetary gear set during operation. Engagement of the locking clutch corresponds to a fixed ratio operating mode. Disengagement of the locking clutch corresponds to a variable ratio operating mode.

Inventors:
MCINDOE GORDON M (US)
PETERS SEBASTIAN J (US)
Application Number:
US2017/033445
Publication Date:
November 23, 2017
Filing Date:
May 19, 2017
Export Citation:
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Assignee:
DANA LTD (US)
International Classes:
F16H3/00; F16H3/093; F16H37/08; F16H25/18
Domestic Patent References:
WO2014039713A12014-03-13
WO2014179717A12014-11-06
Foreign References:
US20030051577A12003-03-20
US20090036247A12009-02-05
US8469856B22013-06-25
US8870711B22014-10-28
US201662333632P2016-05-09
Attorney, Agent or Firm:
EVANS, Stephen P. et al. (Marshall & Melhorn, LLCFour SeaGate - 8th Floo, Toledo OH, 43604, US)
Download PDF:
Claims:
WHAT IS CLAIMED IS:

1. A continuously variable transmission comprising:

a first rotatable shaft operably coupleable to a source of rotational power;

a second rotatable shaft coaxial with the first rotatable shaft, the first rotatable shaft and the second rotatable shaft forming a main axis;

a third rotatable shaft aligned parallel to the main axis;

a fourth rotatable shaft aligned parallel to the third rotatable shaft;

a fifth rotatable shaft arranged coaxial to the main axis, the fifth rotatable shaft configured to transmit an output power;

a variator assembly having a first traction ring assembly and a second traction ring assembly in contact with a plurality of balls, wherein each ball of the plurality of balls has a tiltable axis of rotation, the variator assembly is coaxial with the main axis and the first traction ring assembly is operably coupled to the second rotatable shaft;

a planetary gear set comprising:

a sun gear operably coupled to the second rotatable shaft, a planet carrier operably coupled to the first rotatable shaft, and a ring gear coupled to the second traction ring assembly;

a first-and-third mode clutch coaxial with, and coupled to, the second rotatable shaft;

a second-and-fourth mode clutch coaxial with, and coupled to, the second rotatable shaft;

a first-and-third mode gear set operably coupled to the first-and-third mode clutch, the first-and-third mode gear set operably coupled to the third rotatable shaft;

a second-and-fourth mode gear set operably coupled to the second-and- fourth mode clutch, the second-and-fourth mode gear set operably coupled to the fourth rotatable shaft;

a first gear set operably coupled to the third rotatable shaft;

a second gear set operably coupled to the fourth rotatable shaft; a third gear set operably coupled to the third rotatable shaft;

a fourth gear set operably coupled to the fourth rotatable shaft;

a first synchronizer clutch operably coupled to the first gear set;

a second synchronizer clutch operably coupled the second gear set; a third synchronizer clutch operably coupled to third gear set; and a fourth synchronizer clutch operably coupled to fourth gear set, wherein the first synchronizer clutch, the second synchronizer clutch, the third synchronizer clutch, and the fourth synchronizer clutch are operably coupled to, and coaxial to, the fifth rotatable shaft.

2. The continuously variable transmission of Claim 1 , further comprising a reverse synchronizer clutch operably coupled to and coaxial to the fifth rotatable shaft.

3. The continuously variable transmission of Claim 1 , further comprising a locking clutch operably coupled to the planetary gear set, wherein the locking clutch is adapted to selectively engage a fixed ratio mode of operation. /

4. A continuously variable transmission comprising:

a first rotatable shaft operably coupleable to a source of rotational power;

a second rotatable shaft coaxial with the first rotatable shaft, the first rotatable shaft and the second rotatable shaft forming a main axis;

a third rotatable shaft aligned parallel to the main axis;

a fourth rotatable shaft aligned parallel to the third rotatable shaft;

a fifth rotatable shaft arranged coaxial to the main axis, the fifth rotatable shaft configured to transmit an output power;

a variator assembly having a first traction ring assembly and a second traction ring assembly in contact with a plurality of balls, wherein each ball of the plurality of balls has a tiltable axis of rotation, the variator assembly is coaxial with the main axis, the first traction ring assembly is operably coupled to the second rotatable shaft;

a planetary gear set comprising:

a sun gear operably coupled to the second rotatable shaft, a planet carrier operably coupled to the first rotatable shaft, and a ring gear coupled to the second traction ring assembly;

a first-and-third mode clutch coaxial with, and coupled to, the third rotatable shaft;

a second-and-fourth mode clutch coaxial with, and coupled to, the fourth rotatable shaft;

a transfer coupling configured to couple to the second rotatable shaft, the third rotatable shaft, and the fourth rotatable shaft;

a first gear set operably coupled to the third rotatable shaft;

a second gear set operably coupled to the fourth rotatable shaft;

a third gear set operably coupled to the third rotatable shaft;

a fourth gear set operably coupled to the fourth rotatable shaft;

a first synchronizer clutch operably coupled to the first gear set;

a second synchronizer clutch operably coupled the second gear set; a third synchronizer clutch operably coupled to third gear set; and a fourth synchronizer clutch operably coupled to fourth gear set, wherein the first synchronizer clutch, the second synchronizer clutch, the third synchronizer clutch, and the fourth synchronizer clutch are operably coupled to, and coaxial to, the fifth rotatable shaft. 5. The continuously variable transmission of Claim 4, further comprising a reverse synchronizer clutch operably coupled to and coaxial to the fifth rotatable shaft.

6. The continuously variable transmission of Claim 4, wherein the transfer coupling further comprises a plurality of meshing gears.

7. The continuously variable transmission of Claim 4, further comprising a locking clutch operably coupled to the planetary gear set, wherein the locking clutch is adapted to selectively engage a fixed ratio mode of operation.

8. A continuously variable transmission comprising:

a first rotatable shaft operably coupleable to a source of rotational power;

a second rotatable shaft coaxial with the first rotatable shaft, the first rotatable shaft and the second rotatable shaft forming a main axis;

a third rotatable shaft aligned parallel to the main axis;

a fourth rotatable shaft arranged parallel to the main axis, the fourth rotatable shaft arranged parallel to the third rotatable shaft;

a fifth rotatable shaft arranged coaxial with the main axis;

a sixth rotatable shaft arranged coaxial with the fifth rotatable shaft; a seventh rotatable shaft arranged coaxial with the sixth rotatable shaft; the seventh rotatable shaft configured to transmit an output power;

a variator assembly having a first traction ring assembly and a second traction ring assembly in contact with a plurality of balls, wherein each ball of the plurality of balls has a tiltable axis of rotation, the variator assembly is coaxial with the main axis, the first traction ring assembly is operably coupled to the second rotatable shaft;

a planetary gear set comprising:

a sun gear operably coupled to the second rotatable shaft, a planet carrier operably coupled to the first rotatable shaft, and a ring gear coupled to the second traction ring assembly;

a first-and-third mode clutch coaxial with, and coupled to, the fifth rotatable shaft;

a second-and-fourth mode clutch coaxial with, and coupled to, the sixth rotatable shaft;

a transfer coupling configured to couple to the second rotatable shaft, the third rotatable shaft, and the fourth rotatable shaft; a first gear set operably coupled to the fifth rotatable shaft;

a second gear set operably coupled to the sixth rotatable shaft;

a third gear set operably coupled to the fifth rotatable shaft;

a fourth gear set operably coupled to the sixth rotatable shaft;

a first synchronizer clutch operably coupled to the first gear set;

a second synchronizer clutch operably coupled the second gear set; a third synchronizer clutch operably coupled to third gear set; and a fourth synchronizer clutch operably coupled to fourth gear set;

wherein the first synchronizer clutch and the third synchronizer clutch are operably coupled to, and coaxial to, the third rotatable shaft, and

wherein the second synchronizer clutch and the fourth synchronizer clutch are operably coupled to, and coaxial to, the fourth rotatable shaft.

9. The continuously variable transmission of Claim 8, further comprising a reverse synchronizer clutch operably coupled to and coaxial to the fourth rotatable shaft.

10. The continuously variable transmission of Claim 8, wherein the transfer coupling further comprises a plurality of meshing gears.

11. The continuously variable transmission of Claim 8, further comprising a locking clutch operably coupled to the planetary gear set, wherein the locking clutch is adapted to selectively engage a fixed ratio mode of operation.

12. A continuously variable transmission comprising:

a first rotatable shaft operably coupleable to a source of rotational power;

a second rotatable shaft coaxial with the first rotatable shaft, the first rotatable shaft and the second rotatable shaft forming a main axis;

a third rotatable shaft aligned coaxial to the main axis;

a fourth rotatable shaft aligned coaxial to the third rotatable shaft; a fifth rotatable shaft arranged parallel to the main axis;

a sixth rotatable shaft arranged parallel to the main axis;

a variator assembly having a first traction ring assembly and a second traction ring assembly in contact with a plurality of balls, wherein each ball of the plurality of balls has a tiltable axis of rotation, the variator assembly is coaxial with the main axis, the first traction ring assembly is operably coupled to the second rotatable shaft;

a planetary gear set comprising:

a sun gear operably coupled to the second rotatable shaft, a planet carrier operably coupled to the first rotatable shaft, and a ring gear coupled to the second traction ring assembly;

a first-and-third mode clutch coaxial with, and coupled to, the second rotatable shaft, the first-and-third mode clutch coupled to the third rotatable shaft;

a second-and-fourth mode clutch coaxial with, and coupled to, the second rotatable shaft, the second-and-fourth mode clutch coupled to the fourth rotatable shaft;

a first gear set operably coupled to the third rotatable shaft;

a second gear set operably coupled to the fourth rotatable shaft;

a third gear set operably coupled to the third rotatable shaft;

a fourth gear set operably coupled to the fourth rotatable shaft;

a first synchronizer clutch operably coupled to the first gear set;

a second synchronizer clutch operably coupled the second gear set; a third synchronizer clutch operably coupled to third gear set; and a fourth synchronizer clutch operably coupled to fourth gear set, wherein the first synchronizer clutch and the second synchronizer clutch are operably coupled to, and coaxial to, the fifth rotatable shaft and

wherein the third synchronizer clutch and the fourth synchronizer clutch are operably coupled to, and coaxial to, the sixth rotatable shaft.

13. The continuously variable transmission of Claim 12, further comprising a reverse synchronizer clutch operably coupled to and coaxial to the sixth rotatable shaft.

14. The continuously variable transmission of Claim 12, further comprising a locking clutch operably coupled to the planetary gear set, wherein the locking clutch is adapted to selectively engage a fixed ratio mode of operation.

15. The continuously variable transmission of Claim 12, further comprising a final drive gear set coupled to a seventh rotatable shaft, wherein the seventh rotatable shaft is arranged coaxial to the third rotatable shaft and wherein the seventh rotatable shaft is configured to transmit an output power.

Description:
PLANETARY POWERTRAIN CONFIGURATIONS WITH A BALL VARIATOR CONTINUOUSLY VARIABLE TRANSMISSION USED AS A POWERSPLIT

RELATED APPLICATIONS

The present application claims the benefit of U.S. Provisional Application No. 62/338,921 filed on May 19, 2016, U.S. Provisional

Application No 62/365,703 filed on July 22, 2016, and U.S. Provisional Application No 62/457,339 filed on February 10, 2017, which are

incorporated herein by reference in its entirety.

BACKGROUND

A driveline including a continuously variable transmission allows an operator or a control system to vary a drive ratio in a stepless manner, permitting a power source to operate at its most advantageous rotational speed.

SUMMARY

Provided herein is a continuously variable transmission having: a first rotatable shaft operably coupleable to a source of rotational power; a second rotatable shaft coaxial with the first rotatable shaft, the first rotatable shaft and the second rotatable shaft forming a main axis; a third rotatable shaft aligned parallel to the main axis; a fourth rotatable shaft aligned parallel to the third rotatable shaft; a fifth rotatable shaft arranged coaxial to the main axis, the fifth rotatable shaft configured to transmit an output power; a variator assembly having a first traction ring assembly and a second traction ring assembly in contact with a plurality of balls, wherein each ball of the plurality of balls has a tiltable axis of rotation, the variator assembly is coaxial with the main axis, the first traction ring assembly is operably coupled to the second rotatable shaft; a planetary gear set having a sun gear operably coupled to the second rotatable shaft, a planet carrier operably coupled to the first rotatable shaft and a ring gear coupled to the second traction ring assembly; a first-and-third mode clutch coaxial with, and coupled to, the second rotatable shaft; a second-and-fourth mode clutch coaxial with, and coupled to, the second rotatable shaft; a first- and-third mode gear set operably coupled to the first-and-third mode clutch, the first-and-third mode gear set operably coupled to the third rotatable shaft; a second-and-fourth mode gear set operably coupled to the second-and-fourth mode clutch, the second-and-fourth mode gear set operably coupled to the fourth rotatable shaft; a first gear set operably coupled to the third rotatable shaft; a second gear set operably coupled to the fourth rotatable shaft; a third gear set operably coupled to the third rotatable shaft; a fourth gear set operably coupled to the fourth rotatable shaft; a first synchronizer clutch operably coupled to the first gear set; a second synchronizer clutch operably coupled the second gear set; a third synchronizer clutch operably coupled to third gear set; and a fourth synchronizer clutch operably coupled to fourth gear set, wherein the first synchronizer clutch, the second synchronizer clutch, the third

synchronizer clutch, and the fourth synchronizer clutch are operably coupled to, and coaxial to, the fifth rotatable shaft.

, Provided herein is a continuously variable transmission having: a first rotatable shaft operably coupleable to a source of rotational power; a second rotatable shaft coaxial with the first rotatable shaft, the first rotatable shaft and the second rotatable shaft forming a main axis; a third rotatable shaft aligned parallel to the main axis; a fourth rotatable shaft aligned parallel to the third rotatable shaft; a fifth rotatable shaft arranged coaxial to the main axis, the fifth rotatable shaft configured to transmit an output power; a variator assembly having a first traction ring assembly and a second traction ring assembly in contact with a plurality of balls, wherein each ball of the plurality of balls has a tiltable axis of rotation, the variator assembly is coaxial with the main axis, the first traction ring assembly is operably coupled to the second rotatable shaft; a planetary gear set having a sun gear operably coupled to the second rotatable shaft, a planet carrier operably coupled to the first rotatable shaft, and a ring gear coupled to the second traction ring assembly; a first-and-third mode clutch coaxial with, and coupled to, the third rotatable shaft; a second-and-fourth mode clutch coaxial with, and coupled to, the fourth rotatable shaft; a transfer coupling configured to couple to the second rotatable shaft, the third rotatable shaft, and the fourth rotatable shaft; a first gear set operably coupled to the third rotatable shaft; a second gear set operably coupled to the fourth rotatable shaft; a third gear set operably coupled to the third rotatable shaft; a fourth gear set operably coupled to the fourth rotatable shaft; a first synchronizer clutch operably coupled to the first gear set; a second synchronizer clutch operably coupled the second gear set; a third synchronizer clutch operably coupled to third gear set; and a fourth synchronizer clutch operably coupled to fourth gear set, wherein the first synchronizer clutch, the second synchronizer clutch, the third synchronizer clutch, and the fourth synchronizer clutch are operably coupled to, and coaxial to, the fifth rotatable shaft.

Provided herein is a continuously variable transmission having: a first rotatable shaft operably coupleable to a source of rotational power; a second rotatable shaft coaxial with the first rotatable shaft, the first rotatable shaft and the second rotatable shaft forming a main axis; a third rotatable shaft aligned parallel to the main axis; a fourth rotatable shaft arranged parallel to the main axis, the fourth rotatable shaft arranged parallel to the third rotatable shaft; a fifth rotatable shaft arranged coaxial with the main axis; a sixth rotatable shaft arranged coaxial with the fifth rotatable shaft; a seventh rotatable shaft arranged coaxial with the sixth rotatable shaft; the seventh rotatable shaft configured to transmit an output power; a variator assembly having a first traction ring assembly and a second traction ring assembly in contact with a plurality of balls, wherein each ball of the plurality of balls has a tiltable axis of rotation, the variator assembly is coaxial with the main axis, the first traction ring assembly is operably coupled to the second rotatable shaft; a planetary gear set having a sun gear operably coupled to the second rotatable shaft, a planet carrier operably coupled to the first rotatable shaft, and a ring gear coupled to the second traction ring assembly; a first-and-third mode clutch coaxial with, and coupled to, the fifth rotatable shaft; a second-and-fourth mode clutch coaxial with, and coupled to, the sixth rotatable shaft; a transfer coupling configured to couple to the second rotatable shaft, the third rotatable shaft, and the fourth rotatable shaft; a first gear set operably coupled to the fifth rotatable shaft; a second gear set operably coupled to the sixth rotatable shaft; a third gear set operably coupled to the fifth rotatable shaft; a fourth gear set operably coupled to the sixth rotatable shaft; a first synchronizer clutch operably coupled to the first gear set; a second synchronizer clutch operably coupled the second gear set; a third synchronizer clutch operably coupled to third gear set; and a fourth synchronizer clutch operably coupled to fourth gear set; wherein the first synchronizer clutch and the third synchronizer clutch are operably coupled to, and coaxial to, the third rotatable shaft, wherein the second synchronizer clutch and the fourth synchronizer clutch are operably coupled to, and coaxial to, the fourth rotatable shaft..

Provided herein is a continuously variable transmission having: a first rotatable shaft operably coupleable to a source of rotational power; a second rotatable shaft coaxial with the first rotatable shaft, the first rotatable shaft and the second rotatable shaft forming a main axis; a third rotatable shaft aligned coaxial to the main axis; a fourth rotatable shaft aligned coaxial to the third rotatable shaft; a fifth rotatable shaft arranged parallel to the main axis; a sixth rotatable shaft arranged parallel to the main axis; a variator assembly having a first traction ring assembly and a second traction ring assembly in contact with a plurality of balls, wherein each ball of the plurality of balls has a tiltable axis of rotation, the variator assembly is coaxial with the main axis, the first traction ring assembly is operably coupled to the second rotatable shaft; a planetary gear set having a sun gear operably coupled to the second rotatable shaft, a planet carrier operably coupled to the first rotatable shaft, and a ring gear coupled to the second traction ring assembly; a first-and-third mode clutch coaxial with, and coupled to, the second rotatable shaft, the first-and-third mode clutch coupled to the third rotatable shaft; a second-and-fourth mode clutch coaxial with, and coupled to, the second rotatable shaft, the second-and- fourth mode clutch coupled to the fourth rotatable shaft; a first gear set operably coupled to the third rotatable shaft; a second gear set operably coupled to the fourth rotatable shaft; a third gear set operably coupled to the third rotatable shaft; a fourth gear set operably coupled to the fourth rotatable shaft; a first synchronizer clutch operably coupled to the first gear set; a second synchronizer clutch operably coupled the second gear set; a third synchronizer clutch operably coupled to third gear set; and a fourth synchronizer clutch operably coupled to fourth gear set, wherein the first synchronizer clutch and the second synchronizer clutch are operably coupled to, and coaxial to, the fifth rotatable shaft and wherein the third synchronizer clutch and the fourth synchronizer clutch are operably coupled to, and coaxial to, the sixth rotatable shaft.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the preferred embodiments are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present embodiments will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the preferred embodiments are utilized, and the accompanying drawings of which:

Figure 1 is a side sectional view of a ball-type variator.

Figure 2 is a plan view of a carrier member that is used in the variator of Figure 1.

Figure 3 is an illustrative view of different tilt positions of the ball-type variator of Figure 1.

Figure 4 is a schematic diagram of a powersplit variator.

Figure 5 is a schematic diagram of a powersplit variator having a locking clutch.

Figure 6 is a schematic diagram of another powersplit variator having a locking clutch.

Figure 7 is a schematic diagram of yet another powersplit variator having a locking clutch. Figure 8 is a schematic diagram of a variator having a locking clutch coupled between a first traction ring assembly and a second traction ring assembly.

Figure 9 is a schematic diagram of yet another planetary powersplit continuously variable transmission configured for a rear-wheel drive application.

Figure 10 is a table depicting operating modes of the continuously variable transmissions depicted in Figure 9.

Figure 1 1 is a schematic diagram of yet another planetary powersplit continuously variable transmission configured for a rear-wheel drive application.

Figure 12 is a table depicting operating modes of the continuously variable transmissions depicted in Figure 1 1 .

Figure 3 is a schematic diagram of yet another planetary powersplit continuously variable transmission configured for a rear-wheel drive application.

Figure 14 is a table depicting operating modes of the continuously variable transmissions depicted in Figure 3.

Figure 15 is a schematic diagram of yet another planetary powersplit continuously variable transmission configured for a rear-wheel drive application.

Figure 16 is a table depicting operating modes of the continuously variable transmissions depicted in Figure 15.

Figure 17 is a schematic diagram of a powersplit variator having a stepped planet planetary gear set.

Figure 18 is a schematic diagram of a powersplit variator having a geared differential.

Figure 19 is a schematic diagram of a powersplit variator having dual sun planetary gear set.

Figure 20 is a schematic diagram of a planetary powersplit variator having a number of couplings for transmitting power out of the variator. DETAILED DESCRIPTION

The preferred embodiments will now be described with reference to the accompanying figures, wherein like numerals refer to like elements throughout. The terminology used in the descriptions below is not to be interpreted in any limited or restrictive manner simply because it is used in conjunction with detailed descriptions of certain specific embodiments. Furthermore,

embodiments includes several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing the embodiments described.

Provided herein are configurations of CVTs based on a ball type variators, also known as CVP, for continuously variable planetary. Basic concepts of a ball type Continuously Variable Transmissions are described in United States Patent No. 8,469,856 and 8,870,711 incorporated herein by reference in their entirety. Such a CVT, adapted herein as described

throughout this specification, comprises a number of balls (planets, spheres) 1 , depending on the application, two ring (disc) assemblies with a conical surface in contact with the balls, an input traction ring 2, an output traction ring 3, and an idler (sun) assembly 4 as shown on FIG. 1 . The balls are mounted on tiltable axles 5, themselves held in a carrier (stator, cage) assembly having a first carrier member 6 operably coupled to a second carrier member 7. The first carrier member 6 rotates with respect to the second carrier member 7, and vice versa. In some embodiments, the first carrier member 6 is fixed from rotation while the second carrier member 7 is configured to rotate with respect to the first carrier member, and vice versa. In one embodiment, the first carrier member 6 is provided with a number of radial guide slots 8. The second carrier member 7 is provided with a number of radially offset guide slots 9, as illustrated in FIG. 2. The radial guide slots 8 and the radially offset guide slots 9 are adapted to guide the tiltable axles 5. The axles 5 are adjusted to achieve a desired ratio of input speed to output speed during operation of the CVT. In some embodiments, adjustment of the axles 5 involves control of the position of the first and second carrier members to impart a tilting of the axles 5 and thereby adjusts the speed ratio of the variator. Other types of ball CVTs also exist, but are slightly different.

The working principle of such a CVP of FIG. 1 is shown on FIG. 3. The CVP itself works with a traction fluid. The lubricant between the ball and the conical rings acts as a solid at high pressure, transferring the power from the input ring, through the balls, to the output ring. By tilting the balls' axes, the ratio is changed between input and output. When the axis is horizontal the ratio is one, illustrated in FIG. 3, when the axis is tilted the distance between the axis and the contact point change, modifying the overall ratio. All the balls' axes are tilted at the same time with a mechanism included in the carrier and/or idler. Embodiments disclosed here are related to the control of a variator and/or a CVT using generally spherical planets each having a tiltable axis of rotation that are adjusted to achieve a desired ratio of input speed to output speed during operation. In some embodiments, adjustment of said axis of rotation involves angular misalignment of the planet axis in a first plane in order to achieve an angular adjustment of the planet axis in a second plane that is perpendicular to the first plane, thereby adjusting the speed ratio of the variator. The angular misalignment in the first plane is referred to here as "skew", "skew angle", and/or "skew condition". In one embodiment, a control system

coordinates the use of a skew angle to generate forces between certain contacting components in the variator that will tilt the planet axis of rotation. The tilting of the planet axis of rotation adjusts the speed ratio of the variator.

For description purposes, the term "radial" is used here to indicate a direction or position that is perpendicular relative to a longitudinal axis of a transmission or variator. The term "axial" as used here refers to a direction or position along an axis that is parallel to a main or longitudinal axis of a transmission or variator. For clarity and conciseness, at times similar components labeled similarly (for example, bearing 1011A and bearing 1011 B) will be referred to collectively by a single label (for example, bearing 1011).

As used here, the terms "operationally connected," "operationally coupled", "operationally linked", "operably connected", "operably coupled", "operably linked," "operably coupleable" and like terms, refer to a relationship (mechanical, linkage, coupling, etc.) between elements whereby operation of one element results in a corresponding, following, or simultaneous operation or actuation of a second element. It is noted that in using said terms to describe inventive embodiments, specific structures or mechanisms that link or couple the elements are typically described. However, unless Otherwise specifically stated, when one of said terms is used, the term indicates that the actual linkage or coupling take a variety of forms, which in certain instances will be readily apparent to a person of ordinary skill in the relevant technology.

It should be noted that reference herein to "traction" does not exclude applications where the dominant or exclusive mode of power transfer is through "friction." Without attempting to establish a categorical difference between traction and friction drives here, generally these are typically understood as different regimes of power transfer. Traction drives usually involve the transfer of power between two elements by shear forces in a thin fluid layer trapped between the elements. The fluids used in these applications usually exhibit traction coefficients greater than conventional mineral oils. The traction coefficient (μ) represents the maximum available traction force which would be available at the interfaces of the contacting components and is the ratio of the maximum available drive torque per contact force. Typically, friction drives generally relate to transferring power between two elements by frictional forces between the elements. For the purposes of this disclosure, it should be understood that the CVTs described here operate in both tractive and frictional applications. For example, in the embodiment where a CVT is used for a bicycle application, the CVT operates at times as a friction drive and at other times as a traction drive, depending on the torque and speed conditions present during operation.

As used herein, "creep" or "slip" is the discrete local motion of a body relative to another and is exemplified by the relative velocities of rolling contact components such as the mechanism described herein. "Creep" is

characterized by the slowing of the output because the transmitted force is stretching the fluid film in the direction of rolling. As used herein, the term "ratio droop" refers to the shift of the tilt angle of the ball axis of rotation (sometimes referred to as the ratio angle or gamma angle) due to a compliance of an associated control linkage in proportion to a control force that is in proportion to transmitted torque, wherein the compliance of the control linkage corresponds to a change in the skew angle of the ball axis of rotation. As used herein, the term "load droop" refers to any operating event that reduces the ratio of output speed to input speed as transmitted torque increases.

Typically, synchronizer mechanisms (referred to herein as "synchronizer clutch") used in power transmissions include a dog clutch integrated with a speed-matching device such as a cone-clutch. During operation of the transmission, if the dog teeth of the dog clutch make contact with a gear, and the two parts are spinning at different speeds, the teeth will fail to engage and a loud grinding sound will be heard as they clatter together. For this reason, a synchronizer mechanism or synchronizer clutch is used, which consists of a cone clutch. Before the teeth engage, the cone clutch engages first, which brings the two rotating elements to the same speed using friction. Until synchronization occurs, the teeth are prevented from making contact. It should be appreciated that the exact design of the synchronizer clutch is within a designer's choice for satisfying packaging and performance requirements. A synchronizer clutch is optionally configured to be a two position clutch having an engaged position and a neutral (or free) position. A synchronizer clutch is optionally configured to be a three position clutch having a first engaged position, a second engaged position, and a neutral position. Embodiments disclosed herein use synchronizer clutches to enable the pre-selection of gear sets by a control system (not shown) for smooth transition between operating modes of the transmission. It should be appreciated that the powertrain configurations disclosed herein are optionally configured with other types of selectable torque transmitting devices including, and not limited to, wet clutches, dry clutches, dog clutches, and electromagnetic clutches, among others.

Referring now to FIG. 4, in some embodiments, a powersplit variator 10 includes a first rotatable shaft 11 adapted to receive power from a source of rotational power (not shown). The powersplit variator 10 includes a second rotatable shaft 12 adapted to transmit a rotational power out of the powersplit variator 10. For example, the second rotatable shaft 12 is adapted to couple to a multiple speed gear box (not shown) to provide multiple modes of operation. In some embodiments, the second rotatable shaft 12 is adapted to couple to a fixed ratio automatic transmission such as well-known multiple speed automatic transmissions or simplified versions thereof utilizing alternative friction plate clutches. It should be appreciated that other embodiments of powersplit variators are optionally configured to couple to the power transmission devices disclosed herein. In some embodiments, the powersplit variator 10 includes a variator 13. The variator 13 is optionally configured to be a variator similar to the variator depicted in FIGS. 1 -3. The variator 13 is provided with a first traction ring assembly 15 and a second traction ring assembly 14. In some embodiments, the powersplit variator 10 includes a planetary gear set 16 having a ring gear 17, a planet carrier 18, and a sun gear 19. The ring gear 17 is operably coupled to the second traction ring assembly 14. The sun gear 19 is operably coupled to the second rotatable shaft 12. In some embodiments, the second rotatable shaft 12 is coupled to the first traction ring assembly 15. It should be noted that in some embodiments, the first rotatable shaft 1 1 is adapted to transmit power out of the powersplit variator 10 and the second rotatable shaft 12 is adapted to operably couple to a source of rotational power.

Referring now to FIG. 5, in some embodiments, a powersplit variator 60 includes a first rotatable shaft 61 adapted to receive power from a source of rotational power (not shown). The powersplit variator 60 includes a second rotatable shaft 62 adapted to transmit a rotational power out of the powersplit variator 60. For example, the second rotatable shaft 62 is adapted to couple to a multiple speed gear box (not shown) to provide multiple modes of operation. In some embodiments, the second rotatable shaft 62 is adapted to couple to a fixed ratio automatic transmission such as the General Motors 4L60/4L80 transmission, the Ford Motor Company 4R70, and other well-known multiple speed automatic transmissions or simplified versions thereof utilizing

alternative friction plate clutches. It should be appreciated that embodiments of powersplit variators disclosed here are optionally configured to couple to any power transmission device. In some embodiments, the powersplit variator 60 includes a variator 63. The variator 63 is optionally configured to be a variator similar to the variator depicted in FIGS. 1-3. The variator 63 is provided with a first traction ring assembly 65 and a second traction ring assembly 64. In some embodiments, the powersplit variator 60 includes a planetary gear set 66 having a ring gear 67, a planet carrier 68, and a sun gear 69. The ring gear 67 is operably coupled to the second traction ring assembly 64. The sun gear 69 is operably coupled to the second rotatable shaft 62. In some embodiments, the second rotatable shaft 62 is coupled to the first traction ring assembly 65. In some embodiments, the powersplit variator 60 includes a locking clutch 70 operably coupled to the ring gear 67 and the planet carrier 68. It should be noted that in some embodiments, the first rotatable shaft 61 is adapted to transmit power out of the powersplit variator 60 and the second rotatable shaft 62 is adapted to operably couple to a source of rotational power.

Referring now to FIG. 6, in some embodiments; a powersplit variator 75 includes a first rotatable shaft 76 adapted to receive power from a source of rotational power (not shown). The powersplit variator 75 includes a second rotatable shaft 77 configured to transmit an output power from the powersplit variator 75. The. powersplit variator 75 includes a variator 78 having a first traction ring assembly 80 and a second traction ring assembly 79. The powersplit variator 75 includes a planetary gear set 81 having a ring gear 82, a planet carrier 83, and a sgn gear 84. In some embodiments, the ring gear 82 is operably coupled to the second traction ring assembly 79. The sun gear 84 is coupled to the second rotatable shaft 77. The first traction ring assembly 80 is coupled to the second rotatable shaft 77. In some embodiments, the powersplit variator 75 is provided with a locking clutch 85 coupled to the planet carrier 83 and the sun gear 84. It should be noted that in some embodiments, the first rotatable shaft 76 is adapted to transmit power out of the powersplit variator 75 and the second rotatable shaft 77 is adapted to operably couple to a source of rotational power.

Referring now to FIG. 7, in some embodiments, a powersplit variator 90 includes a first rotatable shaft 91 adapted to receive power from a source of rotational power (not shown). The powersplit variator 90 includes a second rotatable shaft 92 configured to transmit an output power from the powersplit variator 90. The powersplit variator 90 includes a variator 93 having a first traction ring assembly 95 and a second traction ring assembly 94. The powersplit variator 90 includes a planetary gear set 96 having a ring gear 97, a planet carrier 98, and a sun gear 99. In some embodiments, the ring gear 97 is operably coupled to the second traction ring assembly 94. The sun gear 99 is coupled to the second rotatable shaft 92. The first traction ring assembly 95 is coupled to the second rotatable shaft 92. In some embodiments, the powersplit variator 90 is provided with a locking clutch 100 coupled to the ring gear 97 and the sun gear 99. It should be noted that in some embodiments, the first rotatable shaft 91 is adapted to transmit power out of the powersplit variator 90 and the second rotatable shaft 92 is adapted to operably couple to a source of rotational power.

Referring now to FIG. 8, in some embodiments, a variator 160 is provided with a first traction ring assembly 161 and a second traction ring assembly 162 in contact with a plurality of balls. The variator 160 is similar to the variator depicted in FIGS. 1 -3. The first traction ring assembly 161 is coupled to a first rotatable shaft 163. In some embodiments, the first rotatable shaft 163 is adapted to operably couple to a source of rotational power. In other embodiments, the first rotatable shaft 163 is adapted to transmit a power out of the variator 160. The second traction ring assembly 162 is operably coupled to a second rotatable shaft 164. In some embodiments, the second rotatable shaft 164 is adapted to transmit a power out of the variator 160. In other embodiments, the second rotatable shaft 164 is adapted t operably couple to a source of rotational power. The variator 160 is optionally provided with a locking clutch 165 coupled to the first traction ring assembly 161 and the second rotatable shaft 164. The locking clutch 165 is configured to selectively engage the first traction ring assembly 161 and the second rotatable shaft 164 to thereby transmit power from the first rotatable shaft 163 to the second rotatable shaft 164. It should be appreciated that the locking clutch 25, the locking clutch 56, the locking clutch 70, the locking clutch 85, and the locking clutch 100 disclosed herein are optionally configured as wet clutch, dry clutches, synchronizer clutches, one-way clutches, or mechanical diodes. In some embodiments, the continuously variable transmissions disclosed herein are optionally configured to include powersplit variator devices such as the devices disclosed in FIGS. 4-8, and described with related control methods in U.S. Patent Application No. 62/333,632, which is hereby incorporated by reference.

Referring now to FIG. 9, in some embodiments; a continuously variable transmission (CVT) 325 includes a powersplit variator 326 having a first rotatable shaft 327 and a second rotatable shaft 328. In some embodiments, the powersplit variator 326 is configured such as the variators described in FIGS. 1-8. The first rotatable shaft 327 is configured to operably couple to a source of rotational power (not shown). The second rotatable shaft 328 is coupled a first-and-third mode clutch 329. In some embodiments, the second rotatable shaft 328 is coupled to a second-and-fourth mode clutch 330. The first-and-third mode clutch 329 is coupled to a first-and-third-mode gear set

331. The first-and-third mode gear set 331 is coupled to a third rotatable shaft

332. The third rotatable shaft 332 is arranged parallel to the second rotatable shaft 328. The second-and-fourth mode clutch 330 is coupled to a second- and-fourth mode gear set 333 is coupled to a fourth rotatable shaft 334. In some embodiments, the fourth rotatable shaft 334 is parallel to the third rotatable shaft 332.

Still referring to FIG. 9, in some embodiments; the CVT 325 includes a first gear set 335 operably coupled to the third rotatable shaft 332. The first gear set 335 is coupled to a first synchronizer clutch 336. The CVT 325 includes a second gear set 337 operably coupled to the fourth rotatable shaft 334. The second gear set 337 is coupled to a second synchronizer clutch 338. The CVT 325 includes a third gear set 339 operably coupled to the third rotatable shaft 332. The third gear set 339 is coupled to a third synchronizer clutch 340. The CVT 325 includes a fourth gear set 341 operably coupled to the fourth rotatable shaft 334. The fourth gear set 341 is coupled to a fourth synchronizer clutch 342. The CVT 325 includes a reverse gear set 343 operably coupled to the fourth rotatable shaft 334. The reverse gear set 343 is coupled to a reverse synchronizer clutch 344. The first synchronizer clutch 336, the second synchronizer clutch 338, the third synchronizer clutch 340, the fourth synchronizer clutch 342, and the reverse synchronizer clutch 344 are operably coupled to a fifth rotatable shaft 345. The fifth rotatable shaft 345 is arranged coaxial to the second rotatable shaft 328. The fifth rotatable shaft 345 is configured to transmit an output power.

Referring now to FIG. 10, during operation of the CVT 325, multiple modes of operation are achieved through engagement of the various clutching devices to provide modes corresponding to overlapping ranges of speed and torque. Typically, the first mode of operation corresponds to a launch mode of a vehicle from a stop. The subsequent modes engaged correspond to higher speed ranges. Likewise, the reverse mode of operation corresponds to a reverse direction of a vehicle equipped with the CVT 325. The table depicted in FIG. 10, lists the modes of operation for the CVT 325 and indicates with an "x" the corresponding clutch engagement. For mode 1 operation, the first-and- third mode clutch 329 and the first synchronizer clutch 336 are engaged. For mode 2 operation, the second-and-fourth mode clutch 330 and the second synchronizer clutch 338 are engaged. For mode 3 operation, the first-and-third mode clutch 329 and the third synchronizer clutch 340 are engaged. For mode 4 operation, the second-and-fourth mode clutch 330 and the fourth

synchronizer clutch 342 are engaged. For reverse mode operation, the second-and-fourth mode clutch 330 and the reverse synchronizer clutch 344 are engaged. In some embodiments, the powersplit variator 326 is provided with a locking clutch such as the powersplit variators depicted in FIGS. 5-8. In these embodiments, the locking clutch is optionally configured to selectively engage during operation to provide a fixed ratio operating mode as an optional gear in any of the four modes of operation depicted in FIG. 9. During fixed ratio operating modes, power is transmitting through fixed gear ratios and the variator operates at a 1 : 1 speed ratio without transmitting any power. For example, engagement of the locking clutch in mode 1 provides a fixed ratio for vehicle launch from a stop. The locking clutch can be disengaged when a desired vehicle speed is reach and the vehicle continues to operate in mode 1 with power transmitted through the variator. The locking clutch can be engaged during mode 2, mode 3, mode 4, or reverse operation to transmit power through fixed gear ratios and effectively bypass the variator.

Referring now to FIG. 1 , in some embodiments; a continuously variable transmission (CVT) 350 includes a powersplit variator 351 having a first rotatable shaft 352 and a second rotatable shaft 353. In some embodiments, the powersplit variator 351 is configured such as the variators described in FIGS. 1-8. The first rotatable shaft 352 is configured to operably couple to a source of rotational power (not shown). The second rotatable shaft 353 is coupled to a transfer coupling 354. In some embodiments, the transfer coupling 354 is a meshing gear set. In other embodiments, the transfer coupling 354 is optionally configured as a chain-and-sprocket coupling, a belt- and-pulley coupling, or other device configured to transmit rotational power between two or more parallel shafts. The transfer coupling 354 is coupled to a third rotatable shaft 355. The third rotatable shaft 355 is arranged parallel to the second rotatable shaft 353. The transfer coupling 354 is operably coupled to a fourth rotatable shaft 356. The fourth rotatable shaft 356 is arranged parallel to the third rotatable shaft 355. The fourth rotatable shaft 356 is arranged parallel to the second rotatable shaft 353. The third rotatable shaft 355 is operably coupled to a first-and-third mode clutch 357. In some embodiments, the fourth rotatable shaft 356 is operably coupled to a second- and-fourth mode clutch 358.

Still referring to FIG. 11 , in some embodiments; the CVT 350 includes a first gear set 359 operably coupled to the first-and-third mode clutch 357. The first gear set 359 is coupled to a first synchronizer clutch 360. The CVT 350 includes a second gear set 361 operably coupled to the second-and-fourth mode clutch 358. The second gear set 361 is coupled to a second

synchronizer clutch 362. The CVT 350 includes a third gear set 363 operably coupled to the first-and-third mode clutch 357. The third gear set 363 is coupled to a third synchronizer clutch 364. The CVT 350 includes a fourth gear set 365 operably coupled to the second-and-fourth mode clutch 358. The fourth gear set 365 is coupled to a fourth synchronizer clutch 366. The CVT 350 includes a reverse gear set 367 operably coupled to the fourth rotatable shaft 356. The reverse gear set 367 is coupled to a reverse synchronizer clutch 368. The first synchronizer clutch 360, the second synchronizer clutch 362, the third synchronizer clutch 364, the fourth synchronizer clutch 366, and the reverse synchronizer clutch 368 are operably coupled to a fifth rotatable shaft 369. The fifth rotatable shaft 369 is arranged coaxial to the second rotatable shaft 353. The fifth rotatable shaft 369 is arranged parallel to the third rotatable shaft 355 and the fourth rotatable shaft 356. The fifth rotatable shaft 369 is configured to transmit an output power.

Referring now to FIG. 12, during operation of the CVT 350, multiple modes of operation are achieved through engagement of the various clutching devices to provide modes corresponding to overlapping ranges of speed and torque. Typically, the first mode of operation corresponds to a launch mode of a vehicle from a stop. The subsequent modes engaged correspond to higher speed ranges. Likewise, the reverse mode of operation corresponds to a reverse direction of a vehicle equipped with the CVT 350. The table depicted in FrG. 12, lists the modes of operation for the CVT 350 and indicates with an "x" the corresponding clutch engagement. For mode 1 operation, the first-and- third mode clutch 357 and the first synchronizer clutch 360 are engaged. For mode 2 operation, the second-and-fourth mode clutch 358 and the second synchronizer clutch 362 are engaged. For mode 3 operation, the first-and-third mode clutch 357 and the third synchronizer clutch 364 are engaged. For mode 4 operation, the second-and-fourth mode clutch 358 and the fourth

synchronizer clutch 366 are engaged. For reverse mode operation, the second-and-fourth mode clutch 358 and the reverse synchronizer clutch 368 are engaged. In some embodiments, the powersplit variator 351 is provided with a locking clutch such as the powersplit variators depicted in FIGS. 5-8. In these embodiments, the locking clutch is optionally configured to selectively engage during operation to provide a fixed ratio operating mode as an optional gear in any of the four modes of operation depicted in FIG. 11. During fixed ratio operating modes, power is transmitting through fixed gear ratios and the variator operates at a 1 :1 speed ratio without transmitting any power. For example, engagement of the locking clutch in mode 1 provides a fixed ratio for vehicle launch from a stop. The locking clutch can be disengaged when a desired vehicle speed is reach and the vehicle continues to operate in mode 1 with power transmitted through the variator. The locking clutch can be engaged during mode 2, mode 3, mode 4, or reverse operation to transmit power through fixed gear ratios and effectively bypass the variator.

Referring now to FIG. 13, in some embodiments; a continuously variable transmission (CVT) 400 includes a powersplit variator 401 having a first rotatable shaft 402 and a second rotatable shaft 403. In some embodiments, the powersplit variator 401 is configured such as the variators described in FIGS. 1-8. The first rotatable shaft 402 is configured to operably couple to a source of rotational power (not shown). The second rotatable shaft 403 is coupled to a transfer coupling 404. In some embodiments, the transfer coupling 404 is a meshing gear set. In other embodiments, the transfer coupling 404 is optionally configured as a chain-and-sprocket coupling, a belt- and-pulley coupling, or other device configured to transmit rotational power between two or more parallel shafts. The transfer coupling 404 is coupled to a third rotatable shaft 405. The third rotatable shaft 405 is arranged parallel to the second rotatable shaft 403. The transfer coupling 404 is coupled to a fourth rotatable shaft 406. The fourth rotatable shaft 406 is arranged parallel to the third rotatable shaft 405. In some embodiments, the CVT 400 includes a first- and-third mode clutch 407 operably coupled to a fifth rotatable shaft 408. The fifth rotatable shaft 408 is arranged parallel to the third rotatable shaft 405. In some embodiments, the fifth rotatable shaft 408 is configured as a hollow shaft. In some embodiments, the CVT 400 includes a second-and-fourth mode clutch

409 operably coupled to a sixth rotatable shaft 410. The sixth rotatable shaft

410 is coaxial with the fifth rotatable shaft 408. The sixth rotatable shaft 410 is parallel to the third rotatable shaft 405. The fifth rotatable shaft 408 and the sixth rotatable shaft 410 are coaxial with the second rotatable shaft 403. Still referring to FIG. 13, in some embodiments; the CVT 400 includes a first gear set 411 operably coupled to the first-and-third mode clutch 407. The first gear set 411 is coupled to a first synchronizer clutch 412. The CVT 400 includes a second gear set 413 operably coupled to the second-and-fourth mode clutch 409. The second gear set 413 is coupled to a second

synchronizer clutch 414. The CVT 400 includes a third gear set 415 operably coupled to the first-and-third mode clutch 407. The third gear set 415 is coupled to a third synchronizer clutch 416. The CVT 400 includes a fourth gear set 417 operably coupled to the second-and-fourth mode clutch 409. The fourth gear set 417 is coupled to a fourth synchronizer clutch 418. The CVT 400 includes a reverse gear set 419 operably coupled to a reverse

synchronizer clutch 420. The reverse synchronizer clutch 420 is coupled to the fifth rotatable shaft 408. The first synchronizer clutch 412 and the third synchronizer clutch 416 are coupled to the third rotatable shaft 405. The second synchronizer clutch 414 and the fourth synchronizer clutch 418 are operably coupled to the fourth rotatable shaft 406. In some embodiments, a seventh rotatable shaft 421 is operably coupled to the first-and-third mode clutch 407 and the second-and-fourth mode clutch 409. The seventh rotatable shaft 421 is arranged coaxial to the fifth rotatable shaft 408 and the sixth rotatable shaft 410. The seventh rotatable shaft 421 is arranged parallel to the third rotatable shaft 405. The seventh rotatable shaft 421 is configured to transmit an output power.

Referring now to FIG. 14, during operation of the CVT 400, multiple modes of operation are achieved through engagement of the various clutching devices to provide modes corresponding to overlapping ranges of speed and torque. Typically, the first mode of operation corresponds to a launch mode of a vehicle from a stop. The subsequent modes engaged correspond to higher speed ranges. Likewise, the reverse mode of operation corresponds to a reverse direction of a vehicle equipped with the CVT 400. The table depicted in FIG. 14, lists the modes of operation for the CVT 400 and indicates with an "x" the corresponding clutch engagement. For mode 1 operation, the first-and- third mode clutch 407 and the first synchronizer clutch 412 are engaged. For mode 2 operation, the second-and-fourth mode clutch 409 and the second synchronizer clutch 414 are engaged. For mode 3 operation, the first-and-third mode clutch 407 and the third synchronizer clutch 416 are engaged. For mode 4 operation, the second-and-fourth mode clutch 409 and the fourth

synchronizer clutch 418 are engaged. For reverse mode operation, the reverse synchronizer clutch 420 is engaged. In some embodiments, the powersplit variator 401 is provided with a locking clutch such as the powersplit variators depicted in FIGS. 5-8. In these embodiments, the locking clutch is optionally configured to selectively engage during operation to provide a fixed ratio operating mode as an optional gear in any of the four modes of operation depicted in FIG. 24. During fixed ratio operating modes, power is transmitting through fixed gear ratios and the variator operates at a 1 : 1 speed ratio without transmitting any power. For example, engagement of the locking clutch in mode 1 provides a fixed ratio for vehicle launch from a stop. The locking clutch can be disengaged when a desired vehicle speed is reach and the vehicle continues to operate in mode 1 with power transmitted through the variator. The locking clutch can be engaged during mode 2, mode 3, mode 4, or reverse operation to transmit power through fixed gear ratios and effectively bypass the variator.

Referring now to FIG. 15, in some embodiments; a continuously variable transmission (CVT) 450 includes a powersplit variator 451 having a first rotatable shaft 452 and a second rotatable shaft 453. In some embodiments, the powersplit variator 451 is configured such as the variators described in FIGS. 1 -8. The first rotatable shaft 452 is configured to operably couple to a source of rotational power (not shown). The second rotatable shaft 453 is coupled to a first-and-third mode clutch 454 and a second-and-fourth mode clutch 455. In some embodiments, the CVT 450 includes a third rotatable shaft 456 arranged coaxial to the second rotatable shaft 453. The third rotatable shaft 456 is operably coupled to the first-and-third mode clutch 454. In some embodiments, the CVT 450 includes a fourth rotatable shaft 457 arranged coaxial to the third rotatable shaft 456. The fourth rotatable shaft 457 is configured as a hollow shaft through which the third rotatable shaft 456 is positioned. The second-and-fourth mode clutch 455 is coupled to the fourth rotatable shaft 457.

Still referring to FIG. 15, in some embodiments; the CVT 450 includes a first-and-third mode gear set 458 operably coupled to the first-and-third mode clutch 454. The first-and-third mode gear set 458 is coupled to a first synchronizer clutch 459. The first-and-third mode gear set 458 is coupled to a third synchronizer clutch 460. In some embodiments, the first synchronizer clutch 459 is operably coupled to a fifth rotatable shaft 461. The fifth rotatable shaft 461 is arranged parallel to the third rotatable shaft 456. The third synchronizer clutch 460 is operably coupled to a sixth rotatable shaft 462. The sixth rotatable shaft 462 is arranged parallel to the third rotatable shaft 456. The CVT 450 includes a second-and-fourth mode gear set 463 operably coupled to the second-and-fourth mode clutch 455. The second-and-fourth mode gear set 463 is coupled to a second synchronizer clutch 464. The second-and-fourth mode gear set 463 is coupled to a fourth synchronizer clutch 465. The second synchronizer clutch 464 is operably coupled to the fifth rotatable shaft 461. The fourth synchronizer clutch 465 is operably coupled to the sixth rotatable shaft 462. The CVT 450 includes a reverse gear set 466 operably coupled to a reverse synchronizer clutch 467. The reverse

synchronizer clutch 467 is coupled to a sixth rotatable shaft 462. In some embodiments, the CVT 450 includes a final drive gear set 468 coupled to a seventh rotatable shaft 469. The seventh rotatable shaft 469 is arranged coaxial to the third rotatable shaft 456. The seventh rotatable shaft 469 is configured to transmit an output power.

Referring now to FIG. 16, during operation of the CVT 450, multiple modes of operation are achieved through engagement of the various clutching devices to provide modes corresponding to overlapping ranges of speed and torque. Typically, the first mode of operation corresponds to a launch mode of a vehicle from a stop. The subsequent modes engaged correspond to higher speed ranges. Likewise, the reverse mode of operation corresponds to a reverse direction of a vehicle equipped with the CVT 450. The table depicted in FIG. 16, lists the modes of operation for the CVT 450 and indicates with an "x" the corresponding clutch engagement. For mode 1 operation, the first-and- third mode clutch 454 and the first synchronizer clutch 459 are engaged. For mode 2 operation, the second-and-fourth mode clutch 455 and the second synchronizer clutch 464 are engaged. For mode 3 operation, the first-and-third mode clutch 454 and the third synchronizer clutch 460 are engaged. For mode 4 operation, the second-and-fourth mode clutch 455 and the fourth

synchronizer clutch 465 are engaged. For reverse mode operation, the first- and-third mode clutch 454 and the reverse synchronizer clutch 467 are engaged. In some embodiments, the powersplit variator 451 is provided with a locking clutch such as the powersplit variators depicted in FIGS. 5-8. In these embodiments, the locking clutch is optionally configured to selectively engage during operation to provide a fixed ratio operating mode as an optional gear in any of the four modes of operation depicted in FIG. 15. During fixed ratio operating modes, power is transmitting through fixed gear ratios and the variator operates at a 1 : 1 speed ratio without transmitting any power. For example, engagement of the locking clutch in mode 1 provides a fixed ratio for vehicle launch from a stop. The locking clutch can be disengaged when a desired vehicle speed is reach and the vehicle continues to operate in mode 1 with power transmitted through the variator. The locking clutch can be engaged during mode 2, mode 3, mode 4, or reverse operation to transmit power through fixed gear ratios and effectively bypass the variator. It should be appreciated that the CVTs described herein depicted multiple modes of operation, and that it is within a designer's means to configure the CVTs described herein to have two, three, four, five, or more modes to suit a particular application.

Turning now to FIGS. 17-20, embodiments of powersplit variators that are implementable in the continuously variable transmissions disclosed herein will be described. It should be appreciated that it is within a designer's means to use a variety of powersplit variator configurations with the continuously variable transmission configurations described to achieve desired operating and packaging parameters. Referring to FIG. 17, in some embodiments, a powersplit variator 700 includes a first rotatable shaft 701 adapted to receive power from a source of rotational power (not shown). The powersplit variator 700 includes a second rotatable shaft 702 adapted to transmit a rotational power out of the powersplit variator 700. For example, the second rotatable shaft 702 is adapted to couple to a multiple speed gear box (not shown) to provide multiple modes of operation. In some embodiments, the second rotatable shaft 702 is adapted to couple to a fixed ratio automatic transmission such as well-known multiple speed automatic transmissions or simplified versions thereof utilizing alternative friction plate clutches. In some embodiments, the powersplit variator 700 includes a variator 703. The variator 703 is optionally configured to be a variator similar to the variator depicted in FIGS. 1 -3. The variator 703 is provided with a first traction ring assembly 705 and a second traction ring assembly 704. In some embodiments, the powersplit variator 700 includes a planetary gear set 706 having a sun gear 707, a planet carrier 708 configured to support a number of stepped planet gears 709, and a ring gear 710. The ring gear 707 is operably coupled to the second traction ring assembly 704. The sun gear 707 is operably coupled to the second rotatable shaft 702. In some embodiments, the second rotatable shaft 702 is coupled to the first traction ring assembly 705. It should be noted that in some embodiments, the first rotatable shaft 701 is adapted to transmit power out of the powersplit variator 700 and the second rotatable shaft 702 is adapted to operably couple to a source of rotational power.

Referring to FIG. 18, in some embodiments, a powersplit variator 725 includes a first rotatable shaft 726 adapted to receive power from a source of rotational power (not shown). The powersplit variator 725 includes a second rotatable shaft 727 adapted to transmit a rotational power out of the powersplit variator 725. For example, the second rotatable shaft 727 is adapted to couple to a multiple speed gear box (not shown) to provide multiple modes of operation. In some embodiments, the powersplit variator 725 includes a variator 728. The variator 728 is optionally configured to be a variator similar to the variator depicted in FIGS. 1 -3. The variator 728 is provided with a first traction ring assembly 730 and a second traction ring assembly 729. In some embodiments, the powersplit variator 725 includes a differential gear set 706 having a planet carrier 731 operably coupled to the first rotatable shaft 726. The planet carrier 731 is configured to support a number of bevel gears 734 of the well-known conical type typically used in differential gear sets. The bevel gears 734 are coupled to a ring gear 733 and a sun gear 735. The ring gear 733 is coupled to the second traction ring assembly 729. The sun gear 735 is coupled to the second rotatable shaft 727. The first traction ring assembly 730 is coupled to the second rotatable shaft 727. It should be noted that in some embodiments, the first rotatable shaft 726 is adapted to transmit power out of the powersplit variator 725 and the second rotatable shaft 727 is adapted to operably couple to a source of rotational power.

Referring now to FIG. 19, in some embodiments, a powersplit variator 745 includes a first rotatable shaft 746 adapted to receive power from a source of rotational power (not shown). The powersplit variator 745 includes a second rotatable shaft 747 adapted to transmit a rotational power out of the powersplit variator 745. For example, the second rotatable shaft 747 is adapted to couple to a multiple speed gear box (not shown) to provide multiple modes of operation. In some embodiments, the powersplit variator 745 includes a variator 748. The variator 748 is optionally configured to be a variator similar to the variator depicted in FIGS. 1-3. The variator 748 is provided with a first traction ring assembly 750 and a second traction ring assembly 749. In some embodiments, the powersplit variator 745 includes a planetary gear set 751 having a planet carrier 752 configured to support a first array of planet gears 753. The first array of planet gears 753 are coupled to a first sun gear 754.

The planet carrier 752 is configured to support a second array of planet gears

755. The second array of planet gears 755 are coupled to a second sun gear

756. The second sun gear 756 is operably coupled to the second traction ring assembly 749. The first sun gear 754 is operably coupled to the second rotatable shaft 747. In some embodiments, the second rotatable shaft 747 is coupled to the first traction ring assembly 750. It should be noted that in some embodiments, the first rotatable shaft 746 is adapted to transmit power out of the powersplit variator 745 and the second rotatable shaft 747 is adapted to operably couple to a source of rotational power. In some embodiments, the second sun gear 756 is configured to provide an optional power output.

Referring now to FIG. 20, in some embodiments, a powersplit variator 760 is provided with a first rotatable shaft 761 adapted to receive power from a source of rotational power. In some embodiments, the first rotatable shaft 761 is operably coupled to a torque converter device, or other common coupling. The powersplit variator 760 is provided with a variator (CVP) 762 aligned coaxially with the first rotatable shaft 761. In some embodiments, the variator 762 is similar to the variator depicted in FIGS. 1 -3. The variator 762 includes a first traction ring assembly 763 and a second traction ring assembly 764 in contact with a number of balls. In some embodiments, the powersplit variator 760 includes a planetary gear set 765 aligned coaxially with the first rotatable shaft 761 and the variator 762. The planetary gear set 765 includes a ring gear 766, a planet carrier 767, and a sun gear 768. In some embodiments, the planet carrier 767 is coupled to the first rotatable shaft 761. The ring gear 766 is coupled to the second traction ring assembly 764. In some embodiments, the powersplit variator 760 has a first gear set 769 operably coupled to the first traction ring assembly 763. The first gear set 769 is configured to provide a power output path through a first coupling device 770. In some embodiments, the powersplit variator 760 has a second gear set 771 operably coupled to the sun gear 768 and the first gear set 769. The second gear set 771 is configured to provide a power output path through a second coupling device 772. In some embodiments, the powersplit variator 760 has a third gear set 773 operably coupled to the second traction ring assembly 764. The third gear set 771 is configured to provide a power output path through a third coupling device 774. It should be appreciated that the first coupling device 770, the second coupling device 772, and the third coupling device 773 are optionally configured by a designer to achieve desired performance and packaging of the continuously variable transmission.

It should be noted that the description above has provided dimensions for certain components or subassemblies. The mentioned dimensions, or ranges of dimensions, are provided in order to comply as best as possible with certain legal requirements, such as best mode. However, the scope of the embodiments described herein are to be determined solely by the language of the claims, and consequently, none of the mentioned dimensions is to be considered limiting on the inventive embodiments, except in so far as any one claim makes a specified dimension, or range of thereof, a feature of the claim.

While preferred embodiments have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the preferred embodiments. It should be understood that various alternatives to the embodiments described herein may be employed in practice. It is intended that the following claims define the scope of the preferred embodiments and that methods and structures within the scope of these claims and their equivalents be covered thereby.