PLANETARY GEAR SET

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] The present application claims the benefit of US Provisional Patent Application Serial No. 61/905,732, filed November 18, 2013, US Provisional Patent Application Serial No.

62/004,756, filed May 29, 2014, and US Provisional Patent Application Serial No. 62/004,767, filed May 29, 2014 which applications are incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] Automatic and manual transmissions are commonly used on automobile vehicles. Those transmissions are becoming more and more complicated since the engine speed has to be more precisely controlled to limit the fuel consumption and the emissions of cars. This finer control of the engine speed in usual transmissions can only be done by adding more discrete step ratio gears and increasing the overall complexity and cost. Consequently, 6- speed manual transmissions then become more frequently used as are 8 or 9 speed automatic transmissions.

SUMMARY OF THE INVENTION

[0003] The present invention relates to various powerpath layouts consisting in dual modes. The maximum reverse speed is typically close to the forward speed, but the dual mode is intended to provide a slightly higher forward speed, while gaining in efficiency. These configurations might be used for forklift trucks that typically drive in forward and in reverse, but might also be used for other applications. Additionally, the speed characteristic of these configurations is only due to the particular gear ratios chosen. A different set of gear ratios might provide different forward and reverse speed while keeping the same configuration, allowing it to be used in other applications.

Configuration 1, Layout 1

[0004] Provided herein is a variable transmission comprising an input shaft comprising a first gear coupled to a second gear of a first gear set; the first gear set comprising the first gear and a second gear, wherein the second gear is on an offset axle; a variator comprising a first ring assembly drivingly engaged to the second gear, and a second ring assembly coupled to a first sun of a compound planetary gear set; a first set of planet gears of a dual planet gear set coupled to the first sun and drivingly engaged to a ring gear; the dual planet gear set comprising the first set of planet gears and a second set of planet gears; a braking clutch coupled to the ring gear; the second set of planet gears drivingly engaged to a second sun; the second sun drivingly engaged to a third gear of a second gear set; the second gear set comprising the third gear and a fourth gear; the third gear drivingly engaged to the fourth gear and the fourth gear coupled to a first portion of a second clutch on the input shaft; the clutch comprising the first portion and a second portion; the second portion of the second clutch coupled to the first gear on the input shaft and the ICE; the dual planet gear set is coupled to a carrier; wherein the carrier is drivingly engaged to an output gear; wherein the output gear is drivingly engaged to the output of the transmission.

[0005] In some embodiments, the first gear set is an up-speed ratio. In some embodiments, the second gear set is a down-speed ratio.

[0006] In some embodiments, the second clutch is an input coupling clutch.

[0007] In some embodiments, the second sun is connected to the ICE when the input coupling clutch is engaged. In some embodiments, the reverse mode is engaged mode when the input coupling is engaged.

[0008] In some embodiments, the braking clutch engages the direct forward mode when the ring goes to zero speed. In some embodiments, the output gear reverses the carrier output.

Configuration 1, Layout 2

[0009] Provided herein is a variable transmission comprising an input shaft comprising a first gear of a first gear set; the first gear set comprising the first gear and a second gear, the first gear drivingly engaged to the second gear, wherein the second gear is on an offset axle; a variator comprising a first ring assembly drivingly engaged to the second gear, and a second ring assembly coupled to a third gear of a second gear set; the second gear set comprising the third gear and a fourth gear; the fourth gear drivingly engaged to a first sun of a planetary gear set; a first set of planet gears of a dual planet gear set coupled to the first sun and drivingly engaged to a ring gear; the dual planet gear set comprising the first set of planet gears and a second set of planet gears; a braking clutch coupled to the ring gear; the second set of planet gears drivingly engaged to a second sun; the second sun drivingly engaged to a first portion of a second clutch; the second clutch comprising the first portion and a second portion; the second portion of the second clutch coupled to a fifth gear of a third gear set; the third gear set comprising the fifth gear and a sixth gear; the fifth gear drivingly engaged to the sixth gear which is coupled to the offset shaft; the dual planet gear set is coupled to a carrier; wherein the carrier is drivingly engaged to an output gear; wherein the output gear is drivingly engaged to the output of the transmission.

[0010] In some embodiments, the first gear set is an up-speed ratio. In some embodiments, the second gear set is a carrier ratio. [0011] In some embodiments, the second clutch is an input coupling clutch. In some embodiments, the transmission is in reverse mode when the input coupling is engaged.

Configuration 1, Layout 3

[0012] Provided herein is a variable transmission comprising an input shaft comprising a first gear coupled to a second gear of a first gear set; the first gear set comprising the first gear and a second gear, wherein the second gear is on an offset axle; a variator comprising a first ring assembly drivingly engaged to the second gear, and a second ring assembly coupled to a common sun of a compound planetary gear set; a first set of planet gears is coupled to the common sun and is drivingly engaged to a first ring and a first carrier; the first carrier is drivingly engaged to a third gear; a second gear set comprising the third gear and a fourth gear; the third gear drivingly engaged to the fourth gear and the fourth gear coupled to a first portion of a second clutch on the input shaft; the clutch comprising the first portion and a second portion; the second portion of the second clutch coupled to the first gear on the input shaft and the ICE; a second set of planet gears is coupled to the common sun and is drivingly engaged to a second ring and a second carrier; a braking clutch coupled to the second ring gear; the second carrier and the first ring are connected to an output gear; wherein the output gear is drivingly engaged to the output of the transmission.

[0013] In some embodiments, the first gear set is an up-speed ratio. In some embodiments, the second gear set is a down-speed ratio.

[0014] In some embodiments, the second clutch is an input coupling clutch. In some

embodiments, the first carrier is connected to the ICE when the input coupling clutch is engaged.

[0015] In some embodiments, the reverse mode is engaged mode when the input coupling is engaged.

[0016] In some embodiments, the braking clutch engages the direct forward mode when the second ring goes to zero speed. In some embodiments, the output gear reverses the second carrier output.

Configuration 2, Layout 1

[0017] Provided herein is a variable transmission comprising an input shaft comprising a first gear coupled to a second gear of a first gear set; the first gear set comprising the first gear and a second gear, wherein the second gear is on an offset axle; a variator comprising a first ring assembly drivingly engaged to the second gear, and a second ring assembly coupled to a third gear of a second gear set; the second gear set comprising the third gear and a fourth gear; the fourth gear drivingly engaged to a first sun of a planetary gear set; a first set of planet gears of a dual planet gear set coupled to the first sun and drivingly engaged to a ring gear; the dual planet gear set comprising the first set of planet gears and a second set of planet gears; a braking clutch coupled to the ring gear; the second set of planet gears drivingly engaged to a second sun; the second sun drivingly engaged to a first portion of a second clutch; the second clutch comprising the first portion and a second portion; the second portion of the second clutch coupled to a fifth gear of a third gear set; the third gear set comprising the fifth gear and a sixth gear; the fifth gear drivingly engaged to the sixth gear which is coupled to the offset shaft; the dual planet gear set is coupled to a carrier; wherein the carrier is drivingly engaged to an output gear; wherein the output gear is drivingly engaged to the output of the transmission.

[0018] In some embodiments, the first gear set is an up-speed ratio. In some embodiments, the second gear set is a down-speed ratio.

[0019] In some embodiments, the second clutch is a second sun coupling clutch. In some embodiments, the second sun is connected to the ICE when the second sun coupling clutch is engaged. In some embodiments, the forward mode is engaged when the second sun coupling clutch is engaged.

[0020] In some embodiments, the braking clutch engages the direct reverse mode when the ring goes to zero speed.

Configuration 3, Layout 1:

[0021] Provided herein is a variable transmission comprising an input shaft comprising: a first gear coupled to a second gear of a first gear set; the first gear set comprising the first gear and a second gear, wherein the second gear is on an offset axle; the second gear on the offset axle is coupled to a third gear of a second gear set; the second gear set comprising the third gear and a fourth gear; the third gear is drivingly engaged to the fourth gear; a variator comprising a first ring assembly is coupled to the fourth gear, and a second ring assembly coupled to a first sun of a compound planetary gear set; a first set planet gears of a dual planet gear set is coupled to the first sun and drivingly engaged to a ring gear; the dual planet gear set comprising the first set of planet gears and a second set of planet gears; a braking clutch coupled to the ring gear; the second set of planet gears drivingly engaged to a second sun; the second sun drivingly engaged to a first portion of a second clutch; the second clutch comprising the first portion and a second portion; the second portion of the second clutch is coupled to the first gear on the input shaft; the dual planet gear set is coupled to a carrier; wherein the carrier is drivingly engaged to the output of the transmission.

[0022] In some embodiments, the first gear set and second gear set are an up-speed ratio. In some embodiments, the second clutch is an input coupling clutch. [0023] In some embodiments, the second sun is connected to the ICE when the input coupling clutch is engaged. In some embodiments, the reverse mode is engaged.

[0024] In some embodiments, the braking clutch engages the direct forward mode when the ring goes to zero speed.

Configuration 3, Layout 2:

[0025] Provided herein is a variable transmission comprising an input shaft comprising a first gear coupled to a second gear of a first gear set; the first gear set comprising the first gear and the second gear, wherein the second gear is on an offset axle; a variator comprising a first ring assembly drivingly engaged to the second gear, and a second ring assembly coupled to a third gear of a second gear set; the second gear set comprising the third gear and a fourth gear; the fourth gear drivingly engaged to a first sun of a planetary gear set; a first set of planet gears of a dual planet gear set coupled to the first sun and drivingly engaged to a ring gear; the dual planet gear set comprising the first set of planet gears and a second set of planet gears; a braking clutch coupled to the ring gear; the second set of planet gears drivingly engaged to a second sun; the second sun drivingly engaged to a first portion of a second clutch; the second clutch comprising the first portion and a second portion; the second portion of the second clutch is coupled to the first gear on the input shaft; the dual planet gear set is coupled to a carrier; wherein the carrier is drivingly engaged to the output of the transmission.

[0026] In some embodiments, the first gear set and second gear set are an up-speed ratio. In some embodiments, the second clutch is an input coupling clutch.

[0027] In some embodiments, the second sun is connected to the ICE when the input coupling clutch is engaged. In some embodiments, the reverse mode is engaged.

[0028] In some embodiments, the braking clutch engages the direct forward mode when the ring goes to zero speed.

INCORPORATION BY REFERENCE

[0029] 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

[0030] The 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: [0031] FIG. 1 is an illustrative side sectional view of a continuously variable planetary (CVP) transmission;

[0032] FIG. 2 is an illustrative magnified, side sectional view of a ball and ring of the CVP transmission of FIG. 1;

[0033] FIG. 3 is a block diagram of a continuously variable transmission (CVT) used in a vehicle and an off-highway (OH) drivetrain;

[0034] FIG. 4 is a generic layout of Configuration l,an exemplary stick diagram powerpath based on a dual mode solution, each mode being selected by closing a clutch/brake and releasing the other. The CVP is connected to the sun of the planetary on one side and to the ICE through an up-speed ratio on the other side;

[0035] FIG. 5 is a graph of a speed diagram of Configuration 1 for Layouts 1 and 2 of the planetary gear set of the CVT of FIG. 4;

[0036] FIG. 6 is a block diagram of Configuration 1 for Layout 1 of a continuously variable transmission (CVT) according to one embodiment of FIG. 4 used in a vehicle having a dual mode solution comprising a forward mode with a direct CVP mode and a reverse mode composed of a compound coupling planetary that combines input from the ICE and from the CVP into an IVT output;

[0037] FIG. 7 is a block diagram of Configuration 1 for Layout 2 of a continuously variable transmission (CVT) according to another embodiment of FIG. 4 used in a vehicle having a dual mode solution comprising a forward mode with a direct CVP mode and a reverse mode composed of a compound coupling planetary that combines input from the ICE and from the CVP into an IVT output; the main difference being that the CVT and the planetary are no longer on the same shaft;

[0038] FIG. 8 is a graph of a speed diagram of Configuration 1 for Layout 3 of the planetary gear set of the CVT of FIG. 9;

[0039] FIG. 9 is a block diagram of Configuration 1 for Layout 3 of a continuously variable transmission (CVT) according to another embodiment of FIG. 4 used in a vehicle having a dual mode solution comprising a forward mode with a direct CVP mode and a reverse mode composed of a compound coupling planetary that combines input from the ICE and from the CVP into an IVT output; the main difference being the compound planetary utilizes a common sun gear.

[0040] FIG. 10 is another generic layout of Configuration 2, an exemplary stick diagram powerpath based on a dual mode solution, each mode being selected by closing a clutch/brake and releasing the other. The CVP is connected to the sun of the planetary on one side and to the ICE through an up-speed ratio on the other side;

[0041] FIG. 11 is a block diagram of Configuration 2 for Layout 1 of another continuously variable transmission (CVT) according to one embodiment of FIG. 4 used in a vehicle having a dual mode solution. The primary difference with this configuration is that the forward and reverse modes have been interchanged.

[0042] FIG. 12 is another generic layout of Configuration 3, an exemplary stick diagram powerpath based on a dual mode solution, each mode being selected by closing a clutch/brake and releasing the other. The CVP is connected to the sun of the planetary on one side and to the ICE through an up-speed ratio on the other side. This configuration is based on a dual mode solution similar to the one of FIG. 4. The main difference is that the ICE is directly engaged to the middle element of the planetary;

[0043] FIG. 13 is a graph of a speed diagram of Configuration 3 of the planetary gear set of the CVT of FIG. 14;

[0044] FIG. 14 is a block diagram of Configuration 3 for Layout 1 of a continuously variable transmission (CVT) according to one embodiment of FIG. 12 used in a vehicle

[0045] FIG. 15 is another variant block diagram of Configuration 3 for Layout 2 of a

continuously variable transmission (CVT) according to one embodiment of FIG. 12 used in a vehicle. In this configuration, the CVP is on a different shaft than the planetary and an optional ratio is present between the CVP and the first sun of the planetary.

DETAILED DESCRIPTION OF THE INVENTION

[0046] Continuously Variable Transmissions or CVTs are of many types: belts with variable pulleys, toroidal, and conical, for non-limiting example. The principle of a CVT is that it enables the engine to run at its most efficient rotation speed by changing steplessly the transmission ratio in function of the speed of the car and the torque demand (throttle position) of the driver. If needed for example when accelerating, the CVT can also shift to the most optimum ratio providing more power. A CVT can change the ratio from the minimum to the maximum ratio without any interruption of the power transmission, as opposed to the opposite of usual transmissions which require an interruption of the power transmission by disengaging to shift from one discrete ratio to engage the next ratio.

[0047] A specific use of CVTs is the Infinite Variable Transmission or IVT. Where the CVT is limited at positive speed ratios, the IVT configuration can perform a neutral gear and even reverse steplessly. A CVT can be used as an IVT in some driveline configurations. [0048] Provided herein are configurations based on a ball type CVT, also known as CVP (for constant variable planetary) or a variator, herein. Aspects of an example CVT are described in US20040616399 or AU2011224083A1, incorporated herein by reference in their entirety. The type of CVT used herein is comprised a variator comprising a plurality of variator balls 997 as shown in FIG. 1, depending on the application, two discs (input disc 995 and output disc 996) or annular rings (i.e. a first ring assembly and a second ring assembly) each having an engagement portion that engages the variator balls 997. The engagement portions may be in a conical or toroidal convex or concave surface contact with the variator balls 997, as input and output. The variator may include an idler 999 contacting the balls 997 as well as shown on FIG. 1. The variator balls 997 are mounted on axes 998, themselves held in a cage or carrier allowing changing the ratio by tilting the variator balls' axes 998. Other types of ball CVTs also exist like the one produced by Milner but are slightly different. These alternative ball CVTs are

additionally contemplated herein. The working principle generally speaking, of a ball-type variator of a CVT is shown in FIG. 2.

[0049] The variator 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 first ring assembly, through the variator balls, to the second ring assembly. By tilting the variator balls' axes, the ratio can be changed between input and output. When the axis of each of the variator balls is horizontal the ratio is one, when the axis is tilted the distances between the axis and the contact points change, modifying the overall ratio. All the variator balls' axles are tilted at the same time with a mechanism included in the cage.

[0050] As in a car 300, the CVT 301 is used to replace the traditional transmission and is located between the engine 100 (ICE or internal combustion engine) and the differential 304 as shown in FIG. 3. In a typical drivetrain for an Off-Highway (OH) vehicle, a torsional damper 302

(alternatively called a damper) may be introduced between the engine 100 and the CVT 301 to avoid transferring torque peaks and vibrations that could seriously damage the variator 301. In some configurations this damper 302 can be coupled with a clutch 303 for the starting function or to allow the engine to be decoupled from the transmission. Other types of CVT's (apart from ball-type traction drives) can also be used as the variator.

[0051] In addition to the configurations described, where the variator is used directly as the primary transmission, other architectures are possible. Various powerpath layouts can be introduced by adding a number of gears, clutches and simple or compound planetary gear sets. In such configurations, the overall transmission can provide several operating modes; a CVT, an IVT, a combined mode and so on. [0052] Introduced within this specification are different layouts based on a similar working principle of using a planetary connected to the ICE and the CVP to allow powersplitting. They all have a direct drive mode as well as a power recirculation mode allowing zero and low speed. Several examples of architectures are proposed, but the invention is not restricted to these examples and it is assumed that all the layouts that perform similarly to the speed diagrams and generic layouts are part of the invention as well.

[0053] This coupling allows having a better efficiency in one part of the output range, typically the forward part, due to the powersplitting. Additionally, these configurations and their different layouts provide a powered neutral ratio. The spread given through them is sufficient to allow the engine to operate at more optimal points, providing fuel economy, while keeping the same vehicle operating speeds.

[0054] These configurations typically provide a symmetrical range of positive and negative speeds, a feature that is present in many applications such as forklifts. However, modifications of ratios in the gears and planetary gear sets might provide different forward and reverse speed, allowing the use of these configurations in different applications.

[0055] The present invention relates to various powerpath layouts consisting in dual modes. The maximum reverse speed is typically close to the maximum forward speed, but the dual mode is intended to provide a slightly higher forward speed, while gaining in efficiency. These configurations might be used for forklifts trucks that typically drive in forward and in reverse, but might also be used for other applications. Additionally, the speed characteristic of these configurations is only due to the particular gear ratios chosen. A different set of gear ratios might provide different forward and reverse speed while keeping the same configuration, allowing it to be used in other applications.

Configuration 1, Layout 1

[0056] This configuration is based on a dual mode solution, each mode being selected by closing a clutch/brake and releasing the other. The forward mode is a direct CVP mode, engaged by braking an element of the planetary. The planetary gear set wherein an element is braked at zero speed will act as a simple gear ratio. The reverse mode (also providing low forward speeds) is composed of a compound coupling planetary that combines input from the ICE and from the CVP into an IVT output. The CVP is connected to the bottom element of the planetary (when drawing the compound planetary speed diagram) on one side and to the ICE on the other side through an up-speed ratio.

This up-speed ratio tends to increase the speeds and decrease the torque acting on the CVP, allowing for a decrease in the variator size. The ICE is also connected to a middle element of the planetary through a ratio in the reverse mode. It should be noted that the naming of the modes as Forward and Reverse is arbitrarily made and in this case, the reverse mode also provides low forward speeds as well as a powered neutral. However, as this mode covers the whole reverse speed range it has been named Reverse. An optional speed ratio between the CVP and the planetary could also be present.

[0057] As illustrated in the non-limiting FIG. 4, the central part of this configuration is the variator described previously. A ball ramp on each side of the variator provides the clamping force necessary to transfer the torque. Thanks to the planetary, the configuration uses only a CVP and is able to provide standstill and reverse function as an IVP. No starting device like a slipping clutch or torque converter is required, since the IVP capability addresses the starting function. However, these devices can be added to allow a safety disconnect or to start the engine. The ratio after the planetary is there to ensure that the maximum speeds and torques of the vehicle are still achieved. The output of the transmission is made on the upper element from the planetary.

[0058] Referring now to FIG.5, is the speed diagram of the planetary gearset of this first configuration. The four horizontal axes represent respectively, from the bottom to the top, the sun 1 rotation speed 501, the sun 2 rotation speed 502, the carrier rotation speed 503 and the ring rotation speed 504.

[0059] In a first embodiment, the connections are made as follows: In the reverse mode, the second sun of the compound planetary gear set is linked to the ICE through a down speed ratio and then turns at the ICE speed times this down speed ratio, shown as a solid (blue) bar 505 on the second sun axis 502. The ring is free to turn while the first sun is connected to the CVP and thus turns at the ICE speed times the CVP ratio times the up-speed and the optional ratio. In this reverse mode, the solid line 506 in the middle of the carrier axis (green interval) shows the speed achievable by the carrier, the output of the planetary, depending on the variator ratio. A minimum ratio in the CVP brings low forward speed of the vehicle while a maximum speed ratio in the CVP corresponds to the maximum reverse speed. The short dashed (green) lines 507a, 507b show the limits achievable. It should be noted that a positive speed of the carrier/output means a negative speed of the vehicle.

[0060] This mode is a power split mode, meaning that there are multiple power paths that will be used at the same time. A part of the power will flow through the CVP, the planetary first sun, the planets, and going out through the carrier, while a certain amount of the power will directly flow through the second sun, the planets and carrier of the planetary.

[0061] In the forward mode, the second sun is decoupled from the ICE, by opening a clutch, and the ring of the planetary is braked so that the planetary acts as a simple gear reduction. The output of the CVP is still connected to the first sun of the planetary as in the reverse mode. The first ring speed is equal to zero and the output range is shown as a solid line 508 (in red) on the left side of the carrier/output axis. The design is made so that the maximum forward speed of the reverse mode corresponds to the minimum speed of the forward mode, allowing synchronous shifts. However, a slight change in the gear ratios might provide overlap between the two modes or even gap if this is needed for a specific reason.

[0062] Referring now to FIG. 6, is a non-limiting example of this configuration.

[0063] Provided herein is a variable transmission 600 comprising an input shaft 601 comprising a first gear 611 of a first gear set 610; the first gear set comprising the first gear and a second gear; the first gear 611 drivingly engaged to the second gear 612, wherein the second gear 612 is on countershaft 605; a variator 640 comprising a first ring assembly 641 drivingly engaged to the second gear 612, and a second ring assembly 642 coupled to a first sun 631 of a planetary gear set 630; a first set of planet gears 632pl of a dual planet gear set 632 coupled to the first sun 631 and drivingly engaged to a ring gear 633; the dual planet gear set 632 comprising the first set of planet gears 632pl and a second set of planet gears 632p2; a braking clutch 660 coupled to the ring gear 633; the second set of planet gears 632p2 drivingly engaged to a second sun 634; the second sun 634 drivingly engaged to a third gear 621 of a second gear set 620; the second gear set comprising the third gear 621 and a fourth gear 622; the third gear 621 drivingly engaged to the fourth gear 622 and the fourth gear 622 coupled to a first portion 650a of a second clutch 650 on the input shaft 601; the 2 ^nd clutch 650 comprising the first portion 650a and a second portion 650b; the second portion 650b of the second clutch 650 coupled to the first gear 611 on the input shaft 601 and the ICE 100; the dual planet gear set 632 is coupled to a carrier 635; wherein the carrier 635 is drivingly engaged to a fifth gear 671 of an output ratio 670 comprising the fifth gear 671 and a sixth gear 672; wherein the fifth gear 671 is drivingly engaged to the sixth gear 672, and the sixth gear 672 is drivingly engaged to the output of the transmission 680.

[0064] In some embodiments, the first gear set 610 is an up-speed ratio. In some embodiments, the second gear set 620 is a down-speed ratio.

[0065] In some embodiments, the second clutch 650 is an input coupling clutch.

[0066] In some embodiments, the second sun is connected to the ICE when the input coupling clutch is engaged. In some embodiments, the reverse mode is engaged when the input coupling is engaged.

[0067] In some embodiments, the braking clutch 660 engages the direct forward mode when the ring 633 goes to zero speed. In some embodiments, the output gear reverses the carrier 635 output. Configuration 1, Layout 2

[0068] Provided herein is a variable transmission 700 comprising an input shaft 701 comprising a first gear 711 coupled to a second gear 712 of a first gear set 710; the first gear set 710

comprising the first gear 711 and a second gear 712, wherein the second gear 712 is on countershaft 705; a variator 740 comprising a first ring 741 assembly drivingly engaged to the second gear 712, and a second ring assembly 742 coupled to a third gear 771 of a second gear set 770; the second gear set comprising the third gear 771 and a fourth gear 772, wherein the third gear 771 is drivingly engaged to the fourth gear 772 which is coupled to a first sun 733 of a planetary gear set 730; a first set of planet gears 732pl of a dual planet gear set 732 coupled to the first sun 733 and drivingly engaged to a ring gear 731; the dual planet gear set 732

comprising the first set of planet gears 732pl and a second set of planet gears 732p2; a braking clutch 760 coupled to the ring gear 731; the second set of planet gears 732p2 drivingly engaged to a second sun 734; the second sun 734 coupled to a first portion 750a of a second clutch 750; the second clutch 750 comprising the first portion 750a and a second portion 750b; the second portion 750b of the second clutch 750 coupled to a fifth gear 721 of a third gear set 720; the third gear set 720 comprising the fifth gear 721 and a sixth gear 727, the fifth gear 721 drivingly engaged to the sixth gear 722, wherein the sixth gear is coupled to the countershaft 705 and the ICE 100 through the first gear set; the dual planet gear set 732 is coupled to a carrier 735;

wherein the carrier 735 is drivingly engaged to a seventh (output) gear 736; wherein seventh (output) gear 736 is drivingly engaged to the output of the transmission 780.

[0069] In some embodiments, the first gear set is an up-speed ratio. In some embodiments, the second gear set is a carrier ratio.

[0070] In some embodiments, the second clutch is an input coupling clutch. In some

embodiments, the transmission is in reverse mode when the input coupling is engaged.

Configuration 1, Layout 3

[0071] Another variant, Layout 3, uses a different compound planetary in order to perform substantially the same way. The speed diagram is very similar to that previous described, however the arrangement of the elements is slightly different. The first planetary type contains a single carrier with common planets but multiple suns. This variant incorporates a compound planetary gear set having a common sun together with multiple planets and two carriers.

[0072] Referring now to the Layout 3 Speed Diagram shown in FIG. 8, the four horizontal axes represent respectively, from the bottom to the top, the Sun rotation speed 801, the Carrier 1 rotation speed 802, the Carrier 2/Ring 1 rotation speed 803 and the Ring 2 rotation speed 804. [0073] The connections for Layout 3 are made as follows: In the reverse mode, the first carrier of the compound planetary gear set is linked to the ICE through a down speed ratio and then turns at the ICE speed times this down speed ratio, shown as a solid (blue) bar 805 on the carrier 1 axis 802. The second ring is free to turn while the common sun is connected to the CVP and thus turns at the ICE speed times the CVP ratio times the up-speed and the optional ratio. In this reverse mode, the solid (green) interval line 806 crossing the midline of the carrier 2/ring 1 axis 803 shows the output speed achievable by the second carrier/first ring, the output of the planetary, depending on the variator ratio. A minimum ratio in the CVP brings low forward speed of the vehicle while a maximum speed ratio in the CVP corresponds to the maximum reverse speed. The (green) dotted lines 807a, 807b show the limits achievable. It has to be noted that a positive speed of the second carrier/output means negative speed of the vehicle.

[0074] This mode is a power split mode, meaning that there are multiple power paths that will be used at the same time. A part of the power will flow through the CVP, the planetary sun, planet and going out through the second carrier while a certain amount of the power will directly flow through the first carrier, planets and first ring/second carrier of the planetary (the output).

[0075] In the forward mode, the first carrier is decoupled from the ICE, by opening a clutch, and the second ring of the planetary is braked so that the planetary acts as a simple gear reduction. The output of the CVP is still connected to the sun of the planetary as in the reverse mode. The second ring speed is equal to zero and the output range is shown in as a solid (red) line 808 on the left side of the carrier 2/Ring 1 output axis 803. The design is made so that the maximum forward speed of the reverse mode corresponds to the minimum speed of the forward mode, allowing synchronous shifts. However, a slight change in the gear ratios might provide overlap between the two modes or even gap if this is needed for a specific reason.

[0076] Referring now to FIG. 9, provided herein is a variable transmission 900 comprising an input shaft 901 comprising a first gear 911 of a first gear set 910; the first gear set comprising the first gear 911 and a second gear 912, wherein the first gear 911 is drivingly engaged to the second gear 912, wherein the second gear 912 is on countershaft 905; a variator 940 comprising a first ring assembly 941 drivingly engaged to the second gear 912, and a second ring assembly 942 coupled to a common sun 932 of a compound planetary gear set 930; a first set of planet gears 934pl is coupled to the common sun 932 and is drivingly engaged to a first ring 931rl and a first carrier 933cl; the first carrier 933cl is drivingly engaged to a third gear 921; a second gear set 920 comprising the third gear 921 and a fourth gear 922; the third gear 921 drivingly engaged to the fourth gear 922 and the fourth gear 922 coupled to a first portion 950a of an input clutch 950 on the input shaft 901; the input clutch 950 comprising the first portion 950a and a second portion 950b; the second portion 950b of the input clutch 950 coupled to the first gear 911 on the input shaft 901 and the ICE 100; a second set of planet gears 934p2 is coupled to the common sun 932 and is drivingly engaged to a second ring 931r2 and a second carrier 933c2; a braking clutch 960 is coupled to the second ring gear 931r2; the second carrier 933c2 and the first ring 931rl are coupled to a output gear 935; wherein the planetary output gear 935 is drivingly engaged to an output ratio gear 970 and the output ratio gear 970 is drivingly engaged to the output 980 of the transmission.

[0077] In some embodiments, the first gear set is an up-speed ratio. In some embodiments, the second gear set is a down-speed ratio.

[0078] In some embodiments, the second clutch is an input coupling clutch. In some

embodiments, the first carrier is connected to the ICE when the input coupling clutch is engaged.

[0079] In some embodiments, the reverse mode is engaged mode when the input coupling is engaged.

[0080] In some embodiments, the braking clutch engages the direct forward mode when the second ring goes to zero speed. In some embodiments, the output ratio gear reverses the second carrier output.

Configuration 2, Layout 1

[0081] The second configuration is similar to versions of the first configuration except that the forward and reverse modes have been interchanged, as illustrated in FIG. 10. The forward mode is thus a powersplit mode allowing speeds from max forward speed to low reverse speed while the reverse mode is now a direct CVP mode.

[0082] Due to the planetary, this configuration uses only a CVP and is able to provide standstill and reverse function as an IVP. No starting device like a slipping clutch or torque converter is required, since the IVP capability takes care of the starting function. However, these devices can be added to allow a safety disconnect or to start the engine. The ratio gear set after the planetary is there to ensure that the maximum speeds and torques of the vehicle are still achieved.

[0083] An inverted configuration such as this can be performed by adding or removing a gear train to the output. FIG. 11 shows an example of Configuration 1 - Layout 2 in which a gear train has been added in dotted lines in order to reverse the forward and reverse mode. Such a modification can apply equally as well to Layout 1 and 3 from Configuration 1 , but also to any other configuration that can be derived from the general principle of the first configuration presented in this disclosure.

[0084] Provided herein is a variable transmission 1100 comprising an input shaft 1101

comprising a first gear 1111 of a first gear set 1110; the first gear set comprising the first gear 1111 and a second gear 1112, wherein the first gear 1111 is drivingly engaged to the second gear

1112 and the second gear 1112 is on a countershaft 1105; a variator 1140 comprising a first ring assembly 1141 drivingly engaged to the second gear 1112, and a second ring assembly 1142 coupled to a third gear 1171 of a second gear set 1170; the second gear set comprising the third gear 1171 and a fourth gear 1172; the third gear 1171 drivingly engaged to the fourth gear 1172; the fourth gear 1172 coupled to a first sun 1133 of a planetary gear set 1130; a first set of planet gears 1132pl of a dual planet gear set 1132 coupled to the first sun 1133 and drivingly engaged to a ring gear 1131; the dual planet gear set 1132 comprising the first set of planet gears 1132pl and a second set of planet gears 1132p2; a braking clutch 1160 coupled to the ring gear 1131; the second set of planet gears 1132p2 drivingly engaged to a second sun 1134; the second sun 1134 drivingly engaged to a first portion 1150a of a second clutch 1150; the second clutch 1150 comprising the first portion 1150a and a second portion 1150b; the second portion 1150b of the second clutch 1150 coupled to a fifth gear 1121 of a third gear set 1120; the third gear set 1120 comprising the fifth gear 1121 and a sixth gear 1122; the fifth gear 1121 drivingly engaged to the sixth gear 1122 which is coupled to the countershaft 1105 and the ICE 100 through the first gear set; the dual planet gear set 1132 is coupled to a carrier 1135; wherein the carrier 1135 is coupled to an output gear 1136; wherein the output gear is drivingly engaged to an output ratio gear 1180; and the output ratio gear 1180 is drivingly engaged to the output of the transmission 1190.

[0085] In some embodiments, the first gear set is an up-speed ratio. In some embodiments, the second gear set is a down-speed ratio.

[0086] In some embodiments, the second clutch is a second sun coupling clutch. In some embodiments, the second sun is connected to the ICE when the second sun coupling clutch is engaged. In some embodiments, the forward mode is engaged when the second sun coupling clutch is engaged.

[0087] In some embodiments, the braking clutch engages the direct reverse mode when the ring goes to zero speed.

Configuration 3, Layout 1:

[0088] This configuration is based on a dual mode solution similar to the one of configuration 1. The main difference is that the ICE is directly engaged to the middle element of the planetary.

[0089] Each mode is selected by closing a clutch/brake and releasing the other. The

configuration also includes a compound planetary gear set. As illustrated in FIG. 12, the forward mode is a direct CVP mode, engaged by braking an element of the compound planetary; the planetary thus acting as a simple gear ratio. The reverse mode (also providing low forward speeds) is composed of a compound coupling planetary that combines input from the ICE and from the CVP into an IVT output. The CVP is connected to the bottom element of the planetary (when drawing the compound planetary speed diagram) on one side and to the ICE on the other side through an up-speed ratio. This up-speed ratio tends to increase the speeds and decrease the torque acting on the CVP, allowing for a decrease in the variator size. The ICE is also connected to a middle element of the planetary in the reverse mode. It should be noted that the naming of the modes as Forward and Reverse is arbitrarily made, as in this case, the reverse mode also provides low forward speeds as well as a powered neutral. However, as this mode covers the whole reverse speed range it has been named Reverse. An optional speed ratio between the CVP and the planetary can also be present.

[0090] As with other configurations utilizing a planetary, the configuration uses only a CVP and is able to provide standstill and reverse function as an IVP. No starting device like a slipping clutch or torque converter is required, since the IVP capability takes care of the starting function. However, these devices might be added to allow a safety disconnect or to start the engine. A ratio after the planetary is there to ensure that the maximum speeds and torques of the vehicle are still achieved. The output of the transmission is made on the upper element from the planetary.

[0091] FIG. 13 shows the speed diagram of the planetary gearset of this third configuration. The four horizontal axes represent respectively, from the bottom to the top, the sun 1 rotation speed 1301, the sun 2 rotation speed 1302, the carrier rotation speed 1303 and the ring rotation speed 1304.

[0092] In one embodiment, the connections are made as follows. In the reverse mode, the second sun of the compound planetary gear set is directly linked to the ICE and then turns at the ICE speed, shown as a solid vertical (blue) bar 1305 on the second sun axis 1302. The ring is free to turn while the first sun is connected to the CVP and thus turns at the ICE speed times the CVP ratio times the up-speed and the optional ratio. In this reverse mode, the solid (green) output interval 1306 illustrated about the center of the carrier axis 1303, shows the speed achievable by the carrier, the output of the planetary, depending on the variator ratio. A minimum ratio in the CVP produces low forward speed of the vehicle while a maximum speed ratio in the CVP corresponds to the maximum reverse speed. The (green) dotted lines 1307a, 1307b show the limits achievable. It should be noted that a positive speed of the carrier/output means negative speed of the vehicle.

[0093] This mode is a power split mode, meaning that there are multiple power paths that will be used at the same time. A part of the power will flow through the CVP, the planetary first sun, planet and going out through the carrier while a certain amount of the power will directly flow through the second sun, planets and carrier of the planetary. [0094] In the forward mode, the second sun is decoupled from the ICE, by opening a clutch, and the ring of the planetary is braked so that the planetary acts as a simple gear reduction. The output of the CVP is still connected to the first sun of the planetary as in the reverse mode. The first ring speed is equal to zero and the output range, is shown as a solid (red) line 1308 on the left side of the carrier/output axis. The design is made so that the maximum forward speed of the reverse mode corresponds to the minimum speed of the forward mode, allowing synchronous shifts. However, a slight change in the gear ratios might provide overlap between the two modes or even gap if this is needed for a specific reason.

[0095] Referring now to FIG. 14 is a representative example of a physical layout for this configuration. The input is always linked to the up-speed ratio (comprising two gears sets) going to the CVP and to the first member of the input coupling clutch (to engage the "reverse mode"). The CVP output is linked to the first sun of the planetary. A brake allows braking the first ring to zero speed to engage the direct forward mode. The second sun of the planetary is linked to the input coupling clutch and can thus be connected to the ICE when the clutch is engaged. The carrier of the planetary is connected to the output of the transmission.

[0096] Provided herein is a variable transmission 1400 comprising an input shaft 1401

comprising: a first gear 1421 of a first gear set 1420; the first gear set comprising the first gear 1421 and a second gear 1422, wherein the first gear 1421 is drivingly engaged to the second gear 1422, wherein the second gear 1422 is on a countershaft 1405; the second gear 1422 on the countershaft 1405 is coupled to a third gear 1471 of a second gear set 1470; the second gear set 1470 comprising the third gear 1471 and a fourth gear 1472; the third gear 1471 is drivingly engaged to the fourth gear 1472; a variator 1440 comprising a first ring assembly 1441 is coupled to the fourth gear 1472, and a second ring assembly 1442 coupled to a first sun 1433 of a planetary gear set 1430; a first set of planet gears 1432pl of a dual planet gear set 1432 is coupled to the first sun 1433 and drivingly engaged to a ring gear 1431; the dual planet gear set 1432 comprising the first set of planet gears 1432pl and a second set of planet gears 1432p2; a braking clutch 1460 is coupled to the ring gear 1431; the second set of planet gears 1432p2 drivingly engaged to a second sun 1434; the second sun 1434 is drivingly engaged to a first portion 1450a of a second clutch 1450; the second clutch 1450 comprising the first portion 1450a and a second portion 1450b; the second portion 1450b of the second clutch 1450 is coupled to the first gear 1421 on the input shaft 1401 and the ICE 100; the dual planet gear set 1430 is coupled to a carrier 1435; wherein the carrier 1435 is coupled to an output gear 1436, and the output gear 1436 is drivingly engaged to the output of the transmission 1480. [0097] In some embodiments, the first gear set and second gear set are an up-speed ratio. In some embodiments, the second clutch is an input coupling clutch.

[0098] In some embodiments, the second sun is connected to the ICE when the input coupling clutch is engaged. In some embodiments, the reverse mode is engaged.

[0099] In some embodiments, the braking clutch engages the direct forward mode when the ring goes to zero speed.

Configuration 3, Layout 2:

[00100] Referring now to FIG. 15 is an alternate representation of a physical layout for this configuration. In this configuration, the CVP is on a different shaft than the planetary and an optional ratio is present between the CVP and the first sun of the planetary.

[00101] Provided herein is a variable transmission 1500 comprising an input shaft 1501 comprising a first gear 1521 of a first gear set 1520; the first gear set 1520 comprising the first gear 1521 and a second gear 1522; the first gear 1521 is drivingly engaged to the second gear 1522, and the second gear 1522 is on a countershaft 1505; a variator 1540 comprising a first ring assembly 1541 is drivingly engaged to the second gear 1522, a second ring assembly 1542 is coupled to a third gear 1571 of a second gear set 1570; the second gear set 1570 comprising the third gear 1571 and a fourth gear 1572; the fourth gear 1572 is drivingly engaged to a first sun 1533 of a planetary gear set 1530; a first set of planet gears 1532pl of a dual planet gear set 1532 is coupled to the first sun 1533 and drivingly engaged to a ring gear 1531; the dual planet gear set 1532 comprising the first set of planet gears 1532pl and a second set of planet gears 1532p2; a braking clutch 1560 is coupled to the ring gear 1531; the second set of planet gears 1532p2 is drivingly engaged to a second sun 1534; the second sun 1534 is coupled to a first portion 1550a of a second clutch 1550; the second clutch 1550 comprising the first portion 1550a and a second portion 1550b; the second portion 1550b of the second clutch 1550 is coupled to the first gear 1521 on the input shaft 1501 and the ICE 100 through the first gear set; the dual planet gear set 1532 is coupled to a carrier 1535; the carrier 1535 is coupled to an output gear 1536, and the output gear 1536 is drivingly engaged to the output 1580 of the transmission.

[00102] In some embodiments, the first gear set and second gear set are an up-speed ratio.

In some embodiments, the second clutch is an input coupling clutch.

[00103] In some embodiments, the second sun is connected to the ICE when the input coupling clutch is engaged. In some embodiments, the reverse mode is engaged when the input coupling clutch is engaged.

[00104] In some embodiments, the braking clutch engages the direct forward mode when the ring goes to zero speed. [00105] Provided herein are different transmission layouts based on the same principle of having two modes, of which one contains a powered neutral due to a powersplit configuration, and the other one is a direct mode through the CVP. The shifting between the modes in all these configurations is done by engaging and releasing a clutch/brake simultaneously.

[00106] These couplings allow having a better efficiency in one part of the output range due to the powersplitting. Additionally, these configurations and their different layouts provide a powered neutral ratio. The spread given through them is sufficient to allow the engine to operate at more optimal points, providing fuel economy, while keeping the same vehicle operating speeds.

[00107] These configurations typically provide a maximum forward speed that is slightly higher than the negative speeds, a feature that is present in many applications such as premium forklifts. However, modifications of ratios in the gears and planetaries can provide different forward and reverse speed, allowing the use of these configurations in different applications. It is also possible to change this feature by limiting the ratios achievable in the CVP.

[00108] While preferred embodiments of the present invention 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 of the invention described herein may be 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.