WO2018005747A1

WO2018005747A1 - Powertrain

Info

Publication number: WO2018005747A1
Application number: PCT/US2017/039913
Authority: WO
Inventors: Krishna Kumar; William F. WALTZ
Original assignee: Dana Limited
Priority date: 2016-06-29
Filing date: 2017-06-29
Publication date: 2018-01-04

Abstract

A powertrain comprising a first motor/generator (12); a second motor/generator (13); an engine (11); a continuously variable planetary transmission (22) having a plurality of balls, each ball provided with a tiltable axis of rotation, each ball in contact with a first traction ring assembly (23) and a second traction ring assembly (24), and each ball operably coupled to a carrier; a first planetary gear set (14) comprising a first ring gear (15), a first planet carrier (16) operably coupled to the engine (11), and a first sun gear (17) operably coupled to the first motor/generator (12); a second planetary gear set (18) comprising a second ring gear (19) operably coupled to the first traction ring assembly (23), a second planet carrier (20) coupled to the first ring gear (15), and a second sun gear (21) coupled to the second traction ring assembly (24); and a third planetary gear set (26) comprising a third ring gear (27), a third planet carrier (28) and a third sun gear (29), wherein the third planetary gear set (26) is operably coupled to the second motor generator (13).

Description

POWERTRAIN

RELATED APPLICATION

The present application claims the benefit of U.S. Provisional

Application No. 62/356,326 filed on June 29, 2016, which is incorporated herein by reference in its entirety.

BACKGROUND

Hybrid vehicles are enjoying increased popularity and acceptance due in large part to the cost of fuel and greenhouse carbon emission government regulations for internal combustion engine vehicles. Such hybrid vehicles include both an internal combustion engine as well as an electric motor to propel the vehicle.

In current designs for both consuming as well as storing electrical energy, the rotary shaft from a combination electric motor/generator is coupled by a gear train or planetary gear set to the main shaft of an internal combustion engine. As such, the rotary shaft for the electric motor/generator unit rotates in unison with the internal combustion engine main shaft at the fixed ratio of the hybrid vehicle design.

These fixed ratio designs have many disadvantages, for example, the electric motor/generator unit achieves its most efficient operation, both in the sense of generating electricity and also providing additional power to the main shaft of the internal combustion engine, only within a relatively narrow range of revolutions per minute of the motor/generator unit. However, since the previously known hybrid vehicles utilized a fixed speed ratio between the motor/generator unit and the internal combustion engine main shaft, the motor/generator unit oftentimes operates outside its optimal speed range. As such, the overall hybrid vehicle operates at less than optimal efficiency.

Therefore, there is a need for powertrain configurations that improve the efficiency of hybrid vehicles. Regular series-parallel hybrid electric powertrains (powersplit eCVT) are two-motor HEV propulsion systems mated with a planetary gear, and most mild or full parallel hybrid systems are single motor systems with a gearbox or continuously variable transmission coupled with an electric machine. Coupling a ball-type continuously variable planetary (CVP), such as a VariGlide®, with one electric machine enables the creation of a parallel hybrid electric vehicle (HEV) architecture with the CVP functioning as a continuously variable transmission, and the motor providing the functionality of electric assist, starter motor capability, launch assist and regenerative braking. The dual motor variant opens up the possibility of a series-parallel HEV architecture.

Embodiments disclosed herein, coupled with a hybrid supervisory controller that chooses the path of highest efficiency from engine to wheel, provides a means to optimize the operation of the engine and motor/generator, thereby providing a hybrid powertrain that will operate at the best potential overall efficiency point in any mode and also provide torque variability, thereby leading to the best combination of powertrain performance and fuel efficiency that will exceed current industry standards especially in the mild-hybrid and parallel hybrid light vehicle segments.

SUMMARY

Provided herein is a powertrain having: a first motor/generator; a second motor/generator; an engine; a continuously variable planetary transmission having a plurality of balls, each ball provided with a tiltable axis of rotation, each ball in contact with a first traction ring assembly and a second traction ring assembly, and each ball operably coupled to a carrier; a first planetary gear set having a first ring gear, a first planet carrier operably coupled to the engine, a first sun gear operably coupled to the first motor/generator; a second planetary gear set having a second ring gear operably coupled to the first traction ring assembly, a second planet carrier coupled to the first ring gear, a second sun gear coupled to the second traction ring assembly; and a third planetary gear set having a third ring gear operably coupled to the second traction ring assembly, a third planet carrier, and a third sun gear operably coupled to the second motor generator. 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

Novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention 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 hybrid powerpath having a planetary gear system.

Figure 5 is another schematic diagram of a hybrid powerpath having a planetary gear system.

Figure 6 is another schematic diagram of a hybrid powerpath having a planetary gear system.

Figure 7 is a schematic lever diagram of a hybrid powertrain having a ball planetary transmission, two motor/generators, and an engine.

Figure 8 is a schematic lever diagram of another hybrid powertrain having a ball planetary transmission, two motor/generators, and an engine.

Figure 9 is a schematic lever diagram of yet another hybrid powertrain having a ball planetary transmission, two motor/generators, and an engine.

Figure 10 is a schematic lever diagram of yet another hybrid powertrain having a ball planetary transmission, two motor/generators, and an engine.

Figure 11 is a schematic lever diagram of yet another hybrid powertrain having a ball planetary transmission, two motor/generators, and an engine. Figure 12 is a schematic lever diagram of yet another hybrid powertrain having a ball planetary transmission, two motor/generators, and an engine.

Figure 13 is a schematic lever diagram of yet another hybrid powertrain having a ball planetary transmission, two motor/generators, and an engine.

Figure 14 is a schematic lever diagram of yet another hybrid powertrain having a ball planetary transmission, two motor/generators, and an engine.

DETAILED DESCRIPTION OF THE DRAWINGS

These fixed ratio designs have many disadvantages, for example the electric motor/generator unit achieves its most efficient operation, both in the sense of generating electricity and also providing additional power to the main shaft of the internal combustion engine, only within a relatively narrow range of revolutions per minute of the motor/generator unit. However, since the previously known hybrid vehicles utilized a fixed speed ratio between the motor/generator unit and the internal combustion engine main shaft, the motor/generator unit oftentimes operates outside its optimal speed range. As such, the overall hybrid vehicle operates at less than optimal efficiency.

Therefore, there is a need for powertrain configurations that improve the efficiency of hybrid vehicles.

This powertrain relates to electric powertrain configurations and architectures that will be used in hybrid vehicles. The powertrain and/or drivetrain configurations use a ball planetary style continuously variable transmission, such as the VariGlide®, in order to couple power sources used in a hybrid vehicle, for example, combustion engines (internal or external), motors, generators, batteries, and gearing.

A typical ball planetary variator CVT design, such as that described in United States Patent Publication No. 2008/0121487 and in United States Patent No. 8,469,856, both incorporated herein by reference in their entirety, represents a rolling traction drive system, transmitting forces between the input and output rolling surfaces through shearing of a thin fluid film. The technology is called Continuously Variable Planetary (CVP) due to its analogous operation to a planetary gear system. The system consists of an input disc (ring) driven by the power source, an output disc (ring) driving the CVP output, a set of balls fitted between these two discs and a central sun, as illustrated in Figure 1. The balls are able to rotate around their own respective axle by the rotation of two carrier disks at each end of the set of balls axles. The system is also referred to as the Ball-Type Variator.

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 include several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing theembodiments 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, includes a number of balls (planets, spheres) 1 , depending on the application, two traction ring (disc) assemblies with a conical surface contact with the balls, as input 2 and output 3, and an idler (sun) assembly 4 as shown on FIG. 1. Sometimes, the input ring 2 is referred to in illustrations and referred to in text by the label "r1". The output ring 3 is referred to in illustrations and referred to in text by the label "r2". The idler (sun) assembly 4 is referred to in illustrations and referred to in text by the label "s". 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. Sometimes, the carrier assembly is denoted in illustrations and referred to in text by the label "c". These labels are collectively referred to as nodes ("r1", "r2", "s", "c"). 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 substantially fixed from rotation while the second carrier member 7 is configured to rotate with respect to the first carrier member 6, and vice versa. In some embodiments, 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, like the one produced by Milner, 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. The 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 is 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 substantially 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 some embodiments, 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.

As used here, the terms "operationally connected," "operationally coupled", "operationally linked", "operably connected", "operably coupled", "operably linked," 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 is capable of taking 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 will be 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 are capable of operating 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.

Referring now to FIG. 4, in some embodiments using a continuously variable CVP 100 as described previously in FIGS. 1-3, a hybrid powertrain architecture is shown with a fixed ratio planetary powertrain 40, having a first ring (R1) 41 , a second ring (R2) 42, a sun (S) 43, and a carrier (C) 45, wherein an internal combustion engine (ICE) is coupled to the carrier 45. In some embodiments, the carrier 45 is a fixed carrier. A first motor/generator MG1 is configured to control speed/power. The first motor/generator MG1 in the embodiment of FIG. 4 is inside the CVP cam drivers, sometimes referred to as axial force generators operably coupled to the first ring 41 and the second ring 43. In some embodiments, the first motor/generator MG1 operates at speeds as high as 30,000 rpm to 40,000 rpm. One of skill in the art will recognize that the first motor/generator, MG1 , is optionally configured to be small in size for its relative power. A second motor/generator, MG2, is configured to control torque. The second motor/generator MG2 drive layout of FIG. 4 may not take advantage of the CVP multiplication in some embodiments, although in some embodiments it may optionally do so.

Passing to FIG. 5, in some embodiments using a CVPas described previously, a hybrid vehicle is shown with a fixed ratio planetary powertrain 50, having a first ring (R1) 51 , a second ring (R2) 52, a sun (S) 53, and a carrier (C) 55, having an ICE arranged on a high inertia powerpath. In some embodiments, as shown in FIG. 5, the carrier 55 is a fixed carrier. In some embodiments, an infinitely variable transmission having a rotatable carrier is coupled to the ICE to enable reverse operation and vehicle launch. The first motor/generator, MG1 , is configured to control speed/power. The second motor/generator, MG2, is configured to control torque. The ICE is configured to operate in a high inertia powerpath. The ICE is arranged to react inertias of the first motor/generator MG1 and the second motor/generator MG2 under driving conditions of the vehicle. In some embodiments, the ICE operates at high speeds similar to those speeds typical of a gas turbine. In some embodiments, a step up gear is coupled to the ICE to provide a high speed input to the system.

Turning now to FIG. 6, in some embodiments using a CVP, a hybrid vehicle is shown with a fixed ratio planetary powertrain 60, having a first ring (R1) 61 , a second ring (R2) 62, a sun (S) 63, and a carrier (C) 65, having an ICE arranged on a high speed powerpath and configured to react with the first motor/generator, MG1 , and the second motor/generator, MG2, during operation. In some embodiments, as shown in FIG. 6, the carrier 65 is a fixed carrier. The ICE Is configured to operate in a high speed powerpath. The ICE is arranged to react the first motor/generator MG1 and the second

motor/generator MG2 during driving conditions. In some embodiments, the ICE is a very high speed input, such as a gas turbine, or the ICE is coupled to a step up gear.

Embodiments disclosed herein are directed to hybrid vehicle

architectures and/or configurations that incorporate a CVP in place of a regular fixed ratio planetary leading to a continuously variable parallel hybrid. It should be appreciated that the embodiments disclosed herein are adapted to provide hybrid modes of operation that include, but are not limited to series, parallel, series-parallel, or EV (electric vehicle) modes. The core element of the power flow is a CVP, such as a VariGlide®, which functions as a continuously variable transmission having four of nodes (r1 , r2, c, and s), wherein the carrier (c) is grounded, the rings (r1 and r2) are available for output power, and the sun (s) providing a variable ratio, and, in some embodiments, an auxiliary drive system. The CVP enables the engine (ICE) and electric machines

(motor/generators, among others) to run at an optimized overall efficiency. It should be noted that hydro-mechanical components such as hydromotors, pumps, accumulators, among others, are capable of being used in place of the electric machines indicated in the figures and accompanying textual description. Furthermore, it should be noted that embodiments of hybrid architectures disclosed herein incorporate a hybrid supervisory controller that chooses the path of highest efficiency from engine to wheel. Embodiments disclosed herein enable hybrid powertrains that are capable of operating at the best potential overall efficiency point in any mode and also provide torque variability, thereby leading to the optimal combination of powertrain

performance and fuel efficiency. It should be understood that hybrid vehicles incorporating embodiments of the hybrid architectures disclosed herein are capable of including a number of other powertrain components, such as, but not limited to, high-voltage battery pack with a battery management system or ultracapacitor, on-board charger, DC-DC converters, a variety of sensors, actuators, and controllers, among others.

For purposes of description, schematics referred to as lever diagrams are used herein. A lever diagram, also known as a lever analogy diagram, is a translational-system representation of rotating parts for a planetary gear system. In certain embodiments, a lever diagram is provided as a visual aid in describing the functions of the transmission. In a lever diagram, a compound planetary gear set is often represented by a single vertical line ("lever"). The input, output, and reaction torques are represented by horizontal forces on the lever. The lever motion, relative to the reaction point, represents direction of rotational velocities. For example, a typical planetary gear set having a ring gear, a planet carrier, and a sun gear is represented by a vertical line having nodes "R" representing the ring gear, node "S" representing the sun gear, and node "C" representing the planet carrier.

Referring to FIG. 7, in some embodiments, a hybrid powertrain 10 includes a first source of rotational power, such as an internal combustion engine (ICE) 11 , a first motor/generator (M/G1) 12, and a second

motor/generator (M/G2) 13. The hybrid powertrain 10 includes a first planetary gear set 14 having a first ring gear 15, a first planet carrier 16, and a first sun gear 17. In some embodiments, the ICE 11 is operably coupled to the first planet carrier 16. The first motor/generator 12 is operably coupled to the first sun gear 17. In some embodiments, the hybrid powertrain 10 includes a second planetary gear set 18 having a second ring gear 19, a second planet carrier 20, and a second sun gear 21. The first ring gear 15 is coupled to the second planet carrier 20. The hybrid powertrain 10 includes a variator 22 operably coupled to the second planetary gear set 18. The variator 22 has a first traction ring assembly 23 and a second traction ring assembly 24 in contact with a plurality of balls. In some embodiments, the variator 22 is substantially similar to the variator depicted in FIGS. 1-3. The first traction ring assembly 23 is operably coupled to the second ring gear 19. The second sun gear 21 is operably coupled to the second traction ring assembly 24 at a coupling 25. The coupling 25 is configured to receive power transmitted from the second traction ring assembly 24 and the second sun gear 21 to thereby transmit a summed power to a third planetary gear set 26. The third planetary gear set 26 includes a third ring gear 27, a third planet carrier 28, and a third sun gear 29. In some embodiments, the second motor/generator 13 is operably coupled to the third sun gear 29. The coupling 25 is operably coupled to the third ring gear 27. The third planet carrier 28 is adapted to transmit an output power from the hybrid powertrain 10.

Turning now to FIG. 8, in some embodiments, a hybrid powertrain 30 includes a first source of rotational power, such as an internal combustion engine (ICE) 31 , a first motor/generator (M/G1) 32, and a second

motor/generator (M/G2) 33. The hybrid powertrain 30 includes a first planetary gear set 34 having a first ring gear 35, a first planet carrier 36, and a first sun gear 37. In some embodiments, the ICE 31 is operably coupled to the first planet carrier 36. The first motor/generator 32 is operably coupled to the first ring gear 35. In some embodiments, the hybrid powertrain 30 includes a second planetary gear set 38 having a second ring gear 39, a second planet carrier 40, and a second sun gear 41. The first sun gear 37 is coupled to the second planet carrier 40. The hybrid powertrain 30 includes a variator 42 operably coupled to the second planetary gear set 38. The variator 42 has a first traction ring assembly 43 and a second traction ring assembly 44 in contact with a plurality of balls. In some embodiments, the variator 42 is substantially similar to the variator depicted in FIGS. 1-3. The first traction ring assembly 43 is operably coupled to the second ring gear 39. The second sun gear 41 is operably coupled to the second traction ring assembly 44 at a coupling 45. The coupling 45 is configured to receive power transmitted from the second traction ring assembly 44 and the second sun gear 41 to thereby transmit a summed power to the second motor/generator 33. In some embodiments, the hybrid powertrain 30 includes a third planetary gear set 46 having a third ring gear 47, a third planet carrier 48, and a third sun gear 49. In some embodiments, the second motor/generator 33 is operably coupled to the third planet carrier 48. The hybrid powertrain 30 includes a brake 51 coupled to the third sun gear 49. The hybrid powertrain 30 includes a clutch 52 coupled to the third sun gear 49. The third ring gear 47 is adapted to transmit an output power from the hybrid powertrain 30. During operation of the hybrid powertrain 30, the brake 51 and the clutch 52 are selectively engaged to provide multiple modes of operation. In some embodiments, the third sun gear 49 is adapted to transmit an output power from the hybrid powertrain 30. In some

embodiments, the third ring gear 47 is adapted to transmit an output power from the hybrid powertrain 30. It should be appreciated that output power is optionally configured to couple to front wheel drive assemblies, rear wheel drive assemblies, or both depending upon a desired vehicle architecture.

Referring now to FIG. 9, in some embodiments, a hybrid powertrain 55 includes a first source of rotational power, such as an internal combustion engine (ICE) 56, a first motor/generator (M/G1) 57, and a second

motor/generator (M/G2) 58. The hybrid powertrain 55 includes a first planetary gear set 59 having a first ring gear 60, a first planet carrier 61 , and a first sun gear 62. In some embodiments, the ICE 56 is operably coupled to the first planet carrier 61. The first motor/generator 57 is operably coupled to the first sun gear 62. In some embodiments, the hybrid powertrain 55 includes a second planetary gear set 63 having a second ring gear 64, a second planet carrier 65, and a second sun gear 66. The first ring gear 60 is coupled to the second planet carrier 65. The second motor generator 58 is operably coupled to the second sun gear 66. The hybrid powertrain 55 includes a variator 67 operably coupled to the second planetary gear set 63. The variator 67 has a first traction ring assembly 68 and a second traction ring assembly 69 in contact with a plurality of balls. In some embodiments, the variator 67 is substantially similar to the variator depicted in FIGS. 1-3. The first traction ring assembly 68 is operably coupled to the second ring gear 64. In some embodiments, the hybrid powertrain 55 includes a third planetary gear set 70 having a third ring gear 71 , a third planet carrier 72, and a third sun gear 73. The third ring gear 71 is operably coupled to the second traction ring assembly 69. In some embodiments, the hybrid powertrain 55 includes a first brake 75 coupled to the second sun gear 66. The hybrid powertrain 55 includes a second brake 76 coupled to the third sun gear 73. The third ring gear 71 is adapted to transmit an output power from the hybrid powertrain 55. The third planet carrier 72 is adapted to transmit an output power from the hybrid powertrain 55. It should be appreciated that output power is optionally configured to couple to front wheel drive assemblies, rear wheel drive assemblies, or both depending upon a desired vehicle architecture. During operation of the hybrid powertrain 55, the first brake 75 and the second brake 76 are selectively engaged to provide multiple modes of operation.

Turning now to FIG. 10, in some embodiments, a hybrid powertrain 80 includes a first source of rotational power, such as an internal combustion engine (ICE) 81 , a first motor/generator (M/G1) 82, and a second

motor/generator (M/G2) 83. The hybrid powertrain 80 includes a first planetary gear set 84 having a first ring gear 85, a first planet carrier 86, and a first sun gear 87. In some embodiments, the ICE 81 is operably coupled to the first planet carrier 86. The first motor/generator 82 is operably coupled to the first sun gear 87. In some embodiments, the hybrid powertrain 80 includes a second planetary gear set 88 having a second ring gear 89, a second planet carrier 90, and a second sun gear 91. The first ring gear 85 is coupled to the second planet carrier 90. The second motor generator 83 is operably coupled to the second sun gear 91. The hybrid powertrain 80 includes a variator 92 operably coupled to the second planetary gear set 88. The variator 92 has a first traction ring assembly 93 and a second traction ring assembly 94 in contact with a plurality of balls. In some embodiments, the variator 92 is substantially similar to the variator depicted in FIGS. 1-3. The first traction ring assembly 93 is operably coupled to the second ring gear 94. In some embodiments, the hybrid powertrain 80 includes a third planetary gear set 95 having a third ring gear 96, a third planet carrier 97, and a third sun gear 98. The third ring gear 96 is operably coupled to the second traction ring assembly 94. In some embodiments, the third planet carrier 97 is adapted to transmit an output power from the hybrid powertrain 80. The third sun gear 98 is adapted to transmit an output power from the hybrid powertrain 80. It should be appreciated that output power is optionally configured to couple to front wheel drive assemblies, rear wheel drive assemblies, or both depending upon a desired vehicle architecture.

Referring now to FIG. 11 , in some embodiments, a hybrid powertrain 00 includes a first source of rotational power, such as an internal combustion engine (ICE) 101 , a first motor/generator (M/G1) 02, and a second

motor/generator (M/G2) 103. The hybrid powertrain 100 includes a first planetary gear set 104 having a first ring gear 105, a first planet carrier 06, and a first sun gear 107. In some embodiments, the ICE 101 is operably coupled to the first planet carrier 106. The first motor/generator 102 is operably coupled to the first sun gear 107. In some embodiments, the hybrid powertrain 100 includes a second planetary gear set 108 having a second ring gear 109, a second planet carrier 110, and a second sun gear 111. The first ring gear 105 is coupled to the second planet carrier 110. The hybrid powertrain 100 includes a variator 112 operably coupled to the second planetary gear set 108. The variator 112 has a first traction ring assembly 113 and a second traction ring assembly 114 in contact with a plurality of balls. In some embodiments, the variator 112 is substantially similar to the variator depicted in FIGS. 1-3. The first traction ring assembly 113 is operably coupled to the second ring gear 109. The second sun gear 111 is operably coupled to the second traction ring assembly 114 at a coupling 115. The coupling 115 is configured to receive power transmitted from the second traction ring assembly 24 and the second sun gear 21 to thereby transmit a summed power to the second

motor/generator 103. In some embodiments, the hybrid powertrain 100 includes a third planetary gear set 116 includes a third ring gear 117, a third planet carrier 118, and a third sun gear 1 19. In some embodiments, the second motor/generator 103 is operably coupled to the third ring gear 117. The third planet carrier 118 is adapted to transmit an output power from the hybrid powertrain 100. The third sun gear 1 19 is adapted to transmit an output power from the hybrid powertrain 100. In some embodiments, the hybrid powertrain 100 includes a brake 120 operably coupled to the third sun gear 119. It should be appreciated that output power is optionally configured to couple to front wheel drive assemblies, rear wheel drive assemblies, or both depending upon a desired vehicle architecture. During operation of the hybrid powertrain 100, the brake 120 is selectively engage to provide multiple modes of operation.

Referring now to FIG. 12, in some embodiments, a hybrid powertrain 150 includes a first source of rotational power, such as an internal combustion engine (ICE) 121 , a first motor/generator (M/G1) 122, and a second

motor/generator (M/G2) 123. The hybrid powertrain 150 includes a first planetary gear set 124 having a first ring gear 25, a first planet carrier 126, and a first sun gear 127. In some embodiments, the ICE 121 is operably coupled to the first planet carrier 126. The first motor/generator 122 is operably coupled to the first sun gear 127. In some embodiments, the hybrid powertrain 150 includes a second planetary gear set 28 having a second ring gear 129, a second planet carrier 130, and a second sun gear 131. The first ring gear 125 is coupled to the second planet carrier 130. The second motor generator 123 is operably coupled to the second sun gear 131. The hybrid powertrain 150 includes a variator 132 operably coupled to the second planetary gear set 128. The variator 132 has a first traction ring assembly 133 and a second traction ring assembly 134 in contact with a plurality of balls. In some embodiments, the variator 132 is substantially similar to the variator depicted in FIGS. 1-3. The variator 132 includes a carrier assembly 135 adapted support the plurality of balls. The first traction ring assembly 133 is operably coupled to the second ring gear 134. In some embodiments, the hybrid powertrain 150 includes a first clutch 136 coupled between the second ring gear 129 and the first traction ring assembly 133. The hybrid powertrain 150 includes a first brake 137 coupled to the first traction ring assembly 133. The first brake 137 is adapted to selectively ground the first traction ring assembly 133. The hybrid powertrain 150 includes a second clutch 138 coupled between the second planet carrier 130 and the carrier assembly 135. The hybrid powertrain 150 includes a second brake 139 coupled to the carrier assembly 135. The second brake 139 is adapted to selectively ground the carrier assembly 135. The hybrid powertrain 150 includes a third brake 140 coupled to the second sun gear 131. In some embodiments, the hybrid powertrain 150 includes a third planetary gear set 141 having a third ring gear 142, a third planet carrier 143, and a third sun gear 144. The third ring gear 142 is operably coupled to the second traction ring assembly 134. In some embodiments, the third planet carrier 143 is adapted to transmit an output power from the hybrid powertrain 50. The third ring gear 142 is adapted to transmit an output power from the hybrid powertrain 150. It should be appreciated that output power is optionally configured to couple to front wheel drive assemblies, rear wheel drive assemblies, or both depending upon a desired vehicle architecture. In some embodiments, the hybrid powertrain 150 includes a third clutch 145 coupled between the second sun gear 131 and the third sun gear 144. The hybrid powertrain 50 includes a fourth brake 146 coupled to the third sun gear 144.

During operation of the hybrid powertrain 150, an infinitely variable transmission (IVT) mode is achieved when the first brake 137 and the second clutch 138 are engaged while the first clutch 136 and the second brake 139 are disengaged or open. Selective engagement of the third brake 140, the fourth brake 146, and the third clutch 145 provide optional modes of operation in IVT mode. A continuously variable transmission (CVT) mode is achieved when the first brake 137 and the second clutch 138 are disengaged while the first clutch 136 and the second brake 139 are engaged or closed. Selective engagement of the third brake 140, the fourth brake 146, and the third clutch 145 provide optional modes of operation in CVT mode.

Turning now to FIG. 13, in some embodiments, a hybrid powertrain 160 includes a first source of rotational power, such as an internal combustion engine (ICE) 161 , a first motor/generator (M/G1) 162, and a second

motor/generator (M/G2) 163. The hybrid powertrain 160 includes a first planetary gear set 164 having a first ring gear 65, a first planet carrier 166, and a first sun gear 167. In some embodiments, the ICE 161 is operably coupled to the first planet carrier 166. The first motor/generator 162 is operably coupled to the first sun gear 167. In some embodiments, the hybrid powertrain 160 includes a second planetary gear set 168 having a second ring gear 169, a second planet carrier 170, and a second sun gear 171. The first ring gear 165 is coupled to the second planet carrier 170. In some embodiments, the second motor/generator 163 is operably coupled to the second sun gear 171. The hybrid powertrain 160 includes a variator 172 operably coupled to the second planetary gear set 168. The variator 172 has a first traction ring assembly 173 and a second traction ring assembly 174 in contact with a plurality of balls. In some embodiments, the variator 172 is substantially similar to the variator depicted in FIGS. 1-3. The first traction ring assembly 173 is operably coupled to the second ring gear 169. The second sun gear 171 is operably coupled to the second traction ring assembly 174 at a coupling 175. The coupling 175 is configured to receive power transmitted from the second traction ring assembly 174 and the second sun gear 171 to thereby transmit a summed power to a third planetary gear set 176 having a third ring gear 177, a third planet carrier 178, and a third sun gear 179. In some embodiments, the hybrid powertrain 160 includes a first brake 180 operably coupled to the first sun gear 167. The hybrid powertrain 160 includes a second brake 181 coupled to the third ring gear 177. The hybrid powertrain 160 includes a clutch 182 coupled to the third ring gear 177. The third planet carrier 178 is adapted to transmit a first output power from the hybrid powertrain 160. The third sun gear 179 is adapted to transmit a second output power from the hybrid powertrain 160. During operation of the hybrid powertrain 160, the first brake 180, the second brake 181 and the clutch 182 are selectively engaged to provide multiple modes of operation. In some embodiments, the third sun gear 179 is adapted to transmit an output power from the hybrid powertrain 160. In some embodiments, the third ring gear 177 is adapted to transmit an output power from the hybrid powertrain 160. It should be appreciated that output power is optionally configured to couple to front wheel drive assemblies, rear wheel drive assemblies, or both depending upon a desired vehicle architecture.

Referring now to FIG. 14, in some embodiments, a hybrid powertrain 185 includes a first source of rotational power, such as an internal combustion engine (ICE) 186, a first motor/generator (M/G1) 187, and a second

motor/generator (M/G2) 188. The hybrid powertrain 185 includes a first planetary gear set 189 having a first ring gear 190, a first planet carrier 191 , and a first sun gear 192. In some embodiments, the ICE 186 is operably coupled to the first planet carrier 191. The first motor/generator 187 is operably coupled to the first sun gear 192. In some embodiments, the hybrid powertrain 185 includes a second planetary gear set 193 having a second ring gear 194, a second planet carrier 195, and a second sun gear 196. The first ring gear 190 is coupled to the second planet carrier 195. In some embodiments, the second motor/generator 188 is operably coupled to the second sun gear 196. The hybrid powertrain 185 includes a variator 197 operably coupled to the second planetary gear set 189. The variator 197 has a first traction ring assembly 198 and a second traction ring assembly 199 in contact with a plurality of balls. In some embodiments, the variator 197 is substantially similar to the variator depicted in FIGS. 1-3. The first traction ring assembly 198 is operably coupled to the second ring gear 194. The second sun gear 196 is operably coupled to the second traction ring assembly 199 at a coupling 200. The coupling 200 is configured to receive power transmitted from the second traction ring assembly 199 and the second sun gear 196 to thereby transmit a summed power to a third planetary gear set 201 having a third ring gear 202, a third planet carrier 203, and a third sun gear 204. In some embodiments, the hybrid powertrain 185 includes a first brake 205 operably coupled to the first sun gear 192. The hybrid powertrain 185 includes a second brake 206 coupled to the third sun gear 204. The third planet carrier 203 is adapted to transmit a first output power from the hybrid powertrain 185. The third sun gear 204 is adapted to transmit a second output power from the hybrid powertrain 185. During operation of the hybrid powertrain 185, the first brake 205 and the second brake 206 are selectively engaged to provide multiple modes of operation. In some embodiments, the third sun gear 204 is adapted to transmit an output power from the hybrid powertrain 185. In some embodiments, the third ring gear 202 is adapted to transmit an output power from the hybrid powertrain 185. It should be appreciated that output power is optionally configured to couple to front wheel drive assemblies, rear wheel drive assemblies, or both depending upon a desired vehicle architecture.

Provided herein is a powertrain having: a first motor/generator; a second motor/generator; an engine; a continuously variable planetary transmission having a plurality of balls, each ball provided with a tiltable axis of rotation, each ball in contact with a first traction ring assembly and a second traction ring assembly, and each ball operably coupled to a carrier; a first planetary gear set having a first ring gear operably coupled to the first motor/generator, a first planet carrier operably coupled to the engine, and a first sun gear; a second planetary gear set having a second ring gear operably coupled to the first traction ring assembly, a second planet carrier coupled to the first sun gear, a second sun gear coupled to the second traction ring assembly; a third planetary gear set having a third ring gear, a third planet carrier operably coupled to the second motor/generator, and a third sun gear adapted to transmit an output power.

Provided herein is a powertrain having: a first motor/generator; a second motor/generator; an engine; a continuously variable planetary transmission having a plurality of balls, each ball provided with a tiltable axis of rotation, each ball in contact with a first traction ring assembly and a second traction ring assembly, and each ball operably coupled to a carrier; a first planetary gear set having a first ring gear, a first planet carrier operably coupled to the engine, and a first sun gear operably coupled to the first motor/generator; a second planetary gear set having a second ring gear operably coupled to the first traction ring assembly, a second planet carrier coupled to the first ring gear, a second sun gear coupled to the second motor/generator; a third planetary gear set having a third ring gear operably coupled to the second traction ring assembly, a third planet carrier, and a third sun gear.

Provided herein is a powertrain having: a first motor/generator; a second motor/generator; an engine; a continuously variable planetary transmission having a plurality of balls, each ball provided with a tiltable axis of rotation, each ball in contact with a first traction ring assembly and a second traction ring assembly, and each ball operably coupled to a carrier; a first planetary gear set having a first ring gear, a first planet carrier operably coupled to the engine, and a first sun gear operably coupled to the first motor/generator; a second planetary gear set having a second ring gear operably coupled to the first traction ring assembly, a second planet carrier coupled to the first ring gear, a second sun gear coupled to the second traction ring assembly and the second motor/generator; a third planetary gear set having a third ring gear operably coupled to the second motor generator, a third planet carrier, and a third sun gear.

Provided herein is a powertrain having: a first motor/generator; a second motor/generator; an engine; a continuously variable planetary transmission having a plurality of balls, each ball provided with a tiltable axis of rotation, each ball in contact with a first traction ring assembly and a second traction ring assembly, and each ball operably coupled to a carrier; a first planetary gear set having a first ring gear, a first planet carrier operably coupled to the engine, and a first sun gear operably coupled to the first motor/generator; a second planetary gear set having a second ring gear operably coupled to the first traction ring assembly, a second planet carrier coupled to the first ring gear, a second sun gear coupled to the second traction ring assembly and the second motor/generator; a third planetary gear set having a third ring gear, a third planet carrier operably coupled to the second traction ring assembly, and a third sun gear adapted to transmit a first output power.

Provided herein is a powertrain having: a first motor/generator; a second motor/generator; an engine; a continuously variable planetary transmission having a plurality of balls, each ball provided with a tiltable axis of rotation, each ball in contact with a first traction ring assembly and a second traction ring assembly, and each ball operably coupled to a carrier; a first planetary gear set having a first ring gear, a first planet carrier operably coupled to the engine, and a first sun gear operably coupled to the first motor/generator; a second planetary gear set having a second ring gear operably coupled to the first traction ring assembly, a second planet carrier coupled to the first ring gear, a second sun gear coupled to the second traction ring assembly and the second motor/generator; a third planetary gear set having a third ring gear operably coupled to the second traction ring assembly, a third planet carrier adapted to transmit a first output power, and a third sun gear adapted to transmit a second output power.

It should be understood that additional clutches/brakes, step ratios are optionally provided to the hybrid powertrains disclosed herein to obtain varying powerpath characteristics. It should be noted that, in some embodiments, two or more planetary gears and a variator are optionally configured to provide a desired speed ratio range and operating mode to the electric machines. It should be noted that the connections of the engine and the two electric machines to the powerpaths disclosed herein are provided for illustrative example and it is within a designer's means to couple the engine and electric machines to other components of the powertrains disclosed herein.

It should be noted that where an ICE is described, the ICE is capable of being an internal combustion engine (diesel, gasoline, hydrogen) or any powerplant such as a fuel cell system, or any hydraulic/pneumatic powerplant like an air-hybrid system. Along the same lines, the battery is capable of being not just a high voltage pack such as lithium ion or lead-acid batteries, but also ultracapacitors or other pneumatic/hydraulic systems such as accumulators, or other forms of energy storage systems. MG1 and MG2 are capable of representing hydromotors actuated by variable displacement pumps, electric machines, or any other form of rotary power such as pneumatic motors driven by pneumatic pumps. The eCVT architectures depicted in the figures and described in text is capable of being extended to create a hydro-mechanical CVT architectures as well for hydraulic hybrid systems.

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 inventions 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 the 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 invention. It should be understood that various alternatives to the embodiments described herein are capable of being employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.

Claims

CLAIMS WHAT IS CLAIMED IS:

1. A powertrain comprising:

a first motor/generator;

a second motor/generator;

an engine;

a continuously variable planetary transmission having a plurality of balls, each ball provided with a tiltable axis of rotation, each ball in contact with a first traction ring assembly and a second traction ring assembly, and each ball operably coupled to a carrier;

a first planetary gear set comprising a first ring gear, a first planet carrier operably coupled to the engine, a first sun gear operably coupled to the first motor/generator;

a second planetary gear set comprising a second ring gear operably coupled to the first traction ring assembly, a second planet carrier coupled to the first ring gear, a second sun gear coupled to the second traction ring assembly; and

a third planetary gear set comprising a third ring gear, a third planet carrier, and a third sun gear, wherein the third planetary gear set is operably coupled to the second motor generator.

2. The powertrain of Claim 1 , wherein the third ring gear is operably

coupled to the second traction ring assembly, and the third sun gear is operably coupled to the second motor generator.

3. The powertrain of Claim 1 , wherein the third planet carrier is adapted to transmit an output power.

The powertrain of Claim 1 , wherein the third planet carrier is operably coupled to the second motor/generator, and the third sun gear is adapted to transmit an output power.

5. The powertrain of Claim 4, further comprising a first brake operably coupled to the first ring gear.

6. The powertrain of Claim 5, further comprising a second brake operably coupled to the third sun gear.

7. The powertrain of Claim 6, further comprising a clutch operably coupled to the third sun gear, wherein the clutch is adapted to selectively engage and disengage to transmit a first output power.

8. The powertrain of Claim 7, wherein the third ring gear is adapted to transmit a second output power.

9. The powertrain of Claim 1 , wherein the third ring gear is operably

coupled to the second motor generator.

10. The powertrain of Claim 9, further comprising a first brake operably coupled to the third sun gear.

11. The powertrain of Claim 10, wherein the third planet carrier is adapted to transmit a first output power.

12. The powertrain of Claim 11 , wherein the third sun gear is adapted to transmit a second output power.