The prior art introduced few transmissions having common feature. A generic conception as skeleton of this feature is herein presented and representing a new transmission generation.

Application of this generic conception results in several different classes. Some of these classes are modifications of different transmission generations and power transfer mechanisms.

BACKGROUND ART Compactness, reliability, efficiency, high load capacity, low production expenses and longevity are the promising requirements of any kind of transmissions. Manual transmission fulfills these requirements. On the other hand, it has restricting aspects due to its manual operation and its provision of unfavorable output performance when operating with the vehicle engine. Seeking for the better is a heavy task to introduce transmission offering the best of all without hand shifting. Convenience of the driver, automatic transmission is becoming increasingly popular. Even it is not durable and has less capability to transfer higher load capacities when compared with the manual one. Moreover, the characteristic of the automatic transmission is that it has high efficiency variations throughout the wide dynamic range of loads and speed conditions that constitute a typical operating envelope.

Unfortunately, the two mentioned transmissions deviate from the ideal performance characteristics which present constant output power over full speed range. Consequently, the output torque that varies with speed hyperbolically and the ability to keep the vehicle near its torque peak at different conditions are the main requirements which are not satisfied by using such transmissions.

A dramatic departure from these types of discrete ratio transmissions is continuously variable transmissions (CVTs) that meet these requirements. Many configurations are possible.

However, they differ in the principal operation, the geometry and the configuration of the members that transfer power by friction. The superior feature of the CVT is that it provides independent coupling of engine speed and torque output to meet various road conditions. By providing optimal transmission ratios, CVT matches engine performance with road requirements offering high performance and maximizing fuel economy comparable to manual transmission with all the convenience of the automatic transmission.

The two primary restrictions of CVT success are; its potential and durability to withstand high power capacity and the torque impulses; and its higher productive costs. Even with vast

progress supported by many years of experiences to enhance the performance and decrease these disadvantages, friction is the main subject that has to be conceptually handled.

The prior art introduced some CVTs especially in the belt-type having common aspect. This aspect is featured as a conception that is power concept splitting, controlling, and combining of power. Unfortunately, applications are limited due to the consideration of the conception in few transmissions without generalization.

OBJECT OF THE INVENTION The object of the invention is to generalize the conception of splitting, controlling, and combining of power in different power transfer mechanisms and transmissions and consequently, introduce a transmission generation with several new applications and classes having enhanced operation, longevity and low emission. When the conception is considered in different conventional CVTs and other kinds of transmissions, extending their working range for different load and speed requirements incorporated with high overall performance (engine and transmission) and reliability is established.

DISCLOSURE OF THE INVENTION Generalization of the conception of performing three main functions which are power splitting, controlling and combining presents a new transmission generation with several applications. Splitting and controlling of power provide power paths having different characteristics. Final combination of these paths achieves the required output that depends on each power path characteristics. Departure from operational concept of conventional transmissions, this new transmission generation that is so-called controlled power splitting and combining transmission, CPSCT, represents the promising generation of transmissions since it has lower energy losses; increased reliability and load capacity as well as lower transmission weight because of split power paths.

If the power paths are regulated to vary ceaselessly, this will achieve continuously variable output. While fixing the input power, the gear set will offer in any circumstances a hyperbolic relation between the speed and torque. In other words, the multiplication of torque and speed is constantly fixed if the input power is preserved to a certain value. Consequentially, CPSCT provides output requirements like CVT but with different operational concept, more high capacity and superior performance.

The main components of the CPSCT are used to perform the three main functions.

Therefore, two or more mechanisms are attached together in order to fulfil these functions, then CPSCT concept is established. Conventional differential units with controller (s) present power splitter and combiner where planetary gear sets are the most reliable units to perform such

missions due to their enhanced features. Likewise, other differential gear sets can achieve the same purpose. The planetary sets are implemented to branch and/or to combine power as well to magnify and/or reduce torque. These different implementations are used to serve the basic concept of CPSCT. The planetary set that performs power branching is nominated as floating planetary set that has one-input and two outputs without reaction member. The reaction planetary set is used to achieve torque multiplication due to the existence of a reaction member.

The combiner planetary set is used for power combination and usually has its one or two inputs attached to a reaction member to magnify or reduce torque.

Different transmission classes presented herein have a certain form of attachment of the controller (s) with the planetary set (s), to achieve different output torque and speed requirements. This attachment offers a high performance if the controller (s) used in such transmission is reliable and operates with minimum losses. The conventional controllers such as; hydraulic coupling, different friction couplings and torque converter could perform such mission but sometimes with inefficient operational to due to some facts that will be mentioned in latter. According to that, this inventive vane coupling is introduced. The following paragraphs will present and discuss intensely the basic concept and its various aspects besides, other torque regulating devices that could be utilized instead of this coupling, but with less performance.

The invented coupling (vane coupling) introduced in this work is usually used to perform control function due to its particular features. This coupling is vane pump with releasing casing while regulating the relieved oil or preventing oil from discharge. This leads the released case to spin with the rotor together. In this case, the pump will operate as hydraulic coupling that transfers load according to the inside build-up pressure (difference between discharge and suction). The planetary sets and the vane couplings that are usually the main components makes this generation of transmissions has very particular feature because of their conventionality, design and production simplicity.

This invented coupling accomplishes torque transmission through a positive displacement action. This positive displacement action associates with minimum power losses, compactness, simplicity, easy manufactured and less production expenses over the conventional ones. In addition, it is dependable to transmit higher loads and accomplishing this transmission in minimum time rates, besides it has no dependency on the engine operation or performance.

The load transfer with minimum time is confirmed by that the coupling is permanently filled with oil therefore, this offers rapid response and less noise. The vane coupling transfers torque that could be increased according to the progress of build-up pressure. For less transmitted torque, oil is relieved by the hydraulic system, hence establishing low pressure in the coupling. If there is no build-up pressure, the vane coupling is idled or fully non-locked.

Electronically controlled hydraulic system is utilized to control the build-up pressure and to systemize continuously the transmission ratio by regulating the oil pressure in each vane coupling. Electronic controlled valves and sensors will be used to ensure precisely pressure regulation. Oil gear pump is driven by the engine and supplies oil continuously to the couplings.

This coupling operates under two modes; the locking and the non-locking mode. During torque transmission, preventing oil from discharge results in no relative rotation between the rotor and the casing and in such case the coupling acts as torque controller. This kind of operation is called locking mode even with the existence of very small slipping because of oil leak through sliding vanes. On the other hand, if there is relative spinning between the rotor and the casing then, the coupling is working in the non-locking mode and acts as power controller.

Vane coupling represents power controller and not only torque controller when operating in non- locking mode. This is because that power transfer depends on the relative rotation between the coupling input and output, and the transmitted torque.

Performance of vane coupling differs when operates in the locking and non-locking mode.

The efficiency of such coupling when operates in the locking mode is expected to be 99%. This pronounced valve is due to the coupling has low operating pressure and insignificant mechanical losses. The low operating pressures results in low or no slippage. This coupling that is typically like the vane pump could perform build-up pressures fifteen to twenty times the upper operated limit pressure with low slippage. On the other hand, there are no sliding parts except that due to extremely low slippage to allow appearance of mechanical losses.

Mechanical and discharge losses are additional losses when the coupling works in non- locking mode. The axisymmetric configuration of the coupling, the continuous lubrication, and operation with small relative spinning between the rotor and the casing result in suppressing extremely the mechanical tosses and increasing smoothness of operation. Discharge loss is power lost in oil relieving out of the coupling. This power loss is not significant because oil is incompressible. In addition to the small coupling dimensions, the small relative rotation between the rotor and casing and its geometry lead to very small discharge rate. This discharge rate that varies inversely with the operating pressure makes the power loss has no weighed value.

Furthermore, these losses have not a consequential value based on the power in the geartrain is split and only one coupling is usually working in the non-locking mode as this will be mentioned latter. This mode, in some cases, may take small instance of order of few tens of revelations while having slight relative spinning between the rotor and the casing.

Consequently, these would not be of significant detrimental relative to the coupling efficiency.

Therefore, the expected efficiency variation compared with the locking mode is insignificant.

The concept of releasing the casing (housing) and controlling the build-up pressure could be

established to any pump with special configuration to work as hydraulic coupling. This kind of configuration has to ensure axisymmetric shape, rotating of input and output without eccentricity, even load distribution, and operation with low vibration and noise. Asymmetric pump configuration fails to fulfil even load distribution so, couple of the same pump arranged oppositely and having their rotors attached together and their casings connected with each other could satisfy this demand.

The utilization of vane coupling is to serve two primary requirements. First, it is smoothly transmit engine power through oil in the transmission geartrain. Second, it regulates the torque in different power path when addition performance is desired. Besides, it provides an optional creep similar to a conventional automatic transmission for easy low speed driving. Also, it allows a controlled slippage when starting from stop.

Many other couplings could be utilized in CPSCT and each must quantitatively evaluated in term of performance. These couplings are various conventional hydraulic couplings, different kinds of friction couplings,... etc. All these couplings that have usually balking shape can be used to accomplish the main concept of this work. However, each provides controlled torque with noticeable losses. For example, conventional hydraulic coupling transmits little power at low speeds because of its operating characteristics. Besides and as well known, it transmits merely the input power at higher speeds. In the other hand, the friction couplings perform power transfer but in case, achieving this without durability because of its wear. The torque converter could render such torque regulation mission instead of the vane coupling. On the other hand, it has sometimes unsatisfied performance. Particular features of operation are found in the vane coupling overwhelming the other torque regulating devices that are this coupling has constantly higher efficiency and superior load capacity as well as it is compact and dependable.

Different classes could be introduced from CPSCT to fit various requirements and/or to enhance operational features of the different transmissions and power transfer mechanisms.

They are classified according the power transfer mechanism presented and the kind of control used. One or more of the transmission components act as power controllers or have extra function that is power splitting or branching, therefore acting as controlled power splitter (s) or combiner (s). Improving the performance of several transmissions is established by utilizing whole transmission unit or one of its main constitution (s) as controlled power splitter or controlled power combiner or even placing the whole unit or its main constitution (s) in one of the power paths. This improvement for such transmissions is achieved since their operating range is selected (complying with the operating range of CPSCT) and their dependence on their inefficient performance is minimized (part of the power is bypassed). The following paragraphs will discuss the different classes.

The first presented transmission class is arrangements of the planetary sets (two or three sets) with the vane couplings. Two vane couplings used as controllers are attached to two power paths, connected to the planetary set outputs used for power branching (floating planetary set) and located in-between the connections of the planetary sets. The planetary sets are used for power branching and combining, while two vane couplings are utilized for regulating the power characteristics in the power paths even in case of the existence of three power paths. The vane couplings apply on floating planetary set outputs used for power branching different loads thus, providing power branches with different characteristics (similar to vehicle differential unit). Hence, the applied torque on the output members is regulated by the couplings, while speed is controlled according to this corresponding torque. Final combination in planetary gear set is accomplished to perform desired output characteristics.

Vane coupling or any friction or mechanical clutch is used to lock the members of the floating planetary set together for the necessity of power flow starting instance and release this lock after that. Locking these members is used to provide a relative velocity between the inputs and outputs of the vane couplings attached to the power paths and therefore results in flow of power and alteration of the velocity of each of power paths.

The second class, CVTs CPSCT class, considers the power branching in CVTs. This class is typical to what the previous art introduced in the field of CVTs that considers more that one power path. On the other hand, the contribution of this work is to provide more longevity to the different CVT units and to achieve optional two or three power paths in case of utilizing one planetary set and to provide optional three or four paths in case of using two planetary sets. In case of one planetary gear with only two power paths, part of the input power is bypassed and the original input is being shared as input and output at the same time, while the other part is transferred through the original output of the unit. The two parts combine in a planetary set. In case of two planetary sets with only three power paths, the original input and original output to the unit acts as inputs and outputs at the same time. Power splits in the one planetary set to two power branches that pass to the inputs of the CVT unit and flow out of the unit from the its outputs after the power characteristics are controlled. The third power path is the transmission of power from the unit original input to its original output.

In both cases, one planetary set and two planetary sets, extra optional power path is provided by ordinary gears are attached to vane coupling and are used make a mechanical connection between the original input and output. This extra optional power path is performed when this coupling is loaded with regulated non-locking mode operation and consequently, providing power transmission through the ordinary gears with the same transmission ratio between the original input and the original output. Belt or chain may be used instead of the

ordinary gears. Another vane coupling is attached to either the original input or the original output to avoid shuddering of the CVT during starting and stops as the coupling regulates the maximum transmitted torque. The two vane couplings may be used to bypass some or most of the power passing through the original output at load pulsation conditions. The belt-type CVT as example of this class wherein the belt pulleys are the original input and original output.

The third class, torque converter CPSCT class, is achieved by using torque converter as controlled power splitter attached to geartrain. In this case, the torque converter has two outputs that are; the turbine and converter casing (engine) and it operates with regulated bypassed oil.

The regulated bypassed oil controls power in each power path. Power flows through the branch paths to the gear sets with different characteristics and finally combines in a planetary set. The bypassed oil feature (power controller) was not applied before in the automatic transmission and could be used for such transmission during shifting to increase the longevity of the transmission.

The automatic transmission whole unit complies with this class where part of the input power is bypassed and the other part passes through the unit by using the torque converter that acts as controlled power splitter. Final combination of the two power parts is performed in a planetary set. Operation of discrete shifting geartrain (manual geartrain) unit as automatic transmission could be introduced by placing the discrete shifting geartrain in one of the power paths. During the discrete shifting, the oil is bypassed from the torque converter that acts as the vehicle clutch.

The control of bypassed oil may be replaced by vane coupling attached to the turbine while the vane coupling output is the input to the geartrain. The torque converter may also be used as controlled power splitter without utilizing bypassing oil control or vane coupling since the torque converter does power regulation in each power path according to the applied load on each branch.

The fourth class, controlled power splitting vane coupling class, utilizes vane coupling operating in the non-locking mode while providing more than one output (controlled power splitter). This class is configurations of such vane coupling with stepless mechanisms or even arranged with discrete shifting mechanisms like the torque converter CPSCT wherein the vane coupling replaces the torque converter.

The fifth class, extensional class, is developed due to blending of two or more classes and/or changing their main components with others that perform the same function. An example of such class is the blending of second and third class. This establishes beneficial features of the two classes that relate to the performance, few components used and low emission. The converter casing and the turbine of the torque converter are arranged with the CVT unit to provide two or even more power paths. One of the power paths may include the CVT unit or

power may be branched in the unit itself. The power branches combine together in planetary set. Changing of the main components in order to provide extensional modifications can be featured, as an example, by replacing of vane coupling that presents torque or power controller for different classes by any kind of mechanical friction or mechanical couplings that may suit for certain applications. Also, this could be performed by replacing the planetary sets with other differential units.

The sixth class, developmental class, deals with the essential feature of the CPSCT and contributes in developing any power transfer unit or transmission that have sometimes unsatisfied performance when working at certain operating range. This development could be established by placing each of such units in power branch as controller, or using each of them as controlled power splitter or controlled power combiner in any of the previous classes.

Different classes offer more compactness than the manual transmission. This is because of the non-utilizing of the vehicle clutch and the using of compact members that have nearly the same longitudinal and radial dimensions likewise the geartrain in the manual transmission. Most classes of this generation offer a reversible power transfer in both rotation speed and input and output power direction thus, achieving flexibility in design.

BRIEF DESCRIPTION OF THE DRAWING Figures 1-4 illustrate the various configurations and geometries of the vane coupling introduced in this work. Figure 1 shows the vane coupling that has one-input and one-output.

This coupling has a typical view like the vane pump. Figure 2 depicts the vane coupling having two casings and rotor and double sliding vane set. Figure 3 illustrates the vane coupling having two casing and two sliding vane sets. Another configuration of two casing vane coupling is illustrated in Fig. 4.

Figures 5-11 illustrate the different arrangements presented in this work to form several power transmissions. In Fig. 5, two planetary sets with vane couplings are utilized to establish transmission with two power paths. Figure 6 demonstrates the utilizing of three planetary gear sets to provide a geartrain with three power paths. Figures 7 and 8 show the belt-type CVT as an example of any CVT unit operates with the concept of this generation. The arrangement with one planetary set and two vane couplings, Fig. 7, provides optional two or three power paths.

Configuration of the belt type CVT with two planetary sets and two couplings as shown in Fig. 8 provides optional three or four power paths. Figure 9 introduces a torque converter arranged with planetary gear sets as an illustrative example of the automatic transmission development.

Two vane couplings with ordinary gear sets are used as shown Fig. 10 to demonstrate a class of this generation operates with a dependent operational mode of the vane coupling and having special requirements. Figure 10 shows new arrangement of belt-type CVT that is an example of

different kind of CVTs with torque converter and planetary set as a class developed from other two classes.

BEST MODE FOR CARRYING OUT THE INVENTION Figure 1 illustrates the vane coupling which make confusion between it and the vane pump because they have typical view. The coupling is proposed to be designed in axisymmetric configuration having no eccentricity between the rotor 1 and the casing 2 to avoid any unbalanced forces. The rotor 1 contains slots 3 and each slot 3 has sliding vanes 4 moving to stress on the casing 2 by feeding pressurized oil 5. The feeding pressurized oil 5 is a conventional remedy to avoid slippage by achieving different stresses from the sliding vane 4 on the casing 2 according to the various loads. Illumination of slippage is used to maximize the coupling efficiency and hence, the transmission performance and the fuel economy are enhanced.

The rotor 1 propels the casing 2 through transmission oil 6 confined space (chamber) existed between the sliding vanes 4, the rotor 1 and the casing 2. Consequently, torque is transmitted according to the inside build-up pressure. Oil port 7 is attached to the confined space to supply it with oil when there is an increase in its volume and to discharge oil from it when its volume is reduced. Suction and discharge unidirectional valves are attached to the oil ports 7 to control transmitted torque and to prevent the driven member from overrunning the driver member so this coupling could transmit torque in the two rotational directions. The suction unidirectional valves supply transmission oil 6 to the chamber when its pressure is less than the main suction pressure while the discharge unidirectional valves teak oil from the chamber if it exceeds the pressure value of the main discharge pressure. These valves could be placed either in the casing 2 or in the rotor 1.

As there is a relative spinning between the rotor 1 and the casing 2, the displacement volume changes according to the inner contour of the casing 2. The suction and pressure sides are frequently reverse. In such case, the coupling transmits fluctuated torque and this fluctuation is illuminated when the number of sliding vanes 4 is increased. The relative spinning between the rotor 1 and the casing 2 and small ovality in the casing 2 without eccentricity provides longevity, avoidance of vibration, smoothness in operation and reliability in performance, In addition, it is used to extend the operational speed of the geartrain to accommodate high-speed engines.

Various configurations are possible according to their geometry and the provided number of outputs. Figure 2 illustrates the vane coupling that provides one output, handles high torque capacities and reduces torque transmission fluctuations. It consists of two casings 8 and 9 and one rotor 1. The input to this coupling is the inner casing 8 while the output is the rotor 1 and the outer casing 9 in one piece. The contour of the rotor 1 has certain oval profile where its major

axis is placed normal to that of the outer casing 9. This profile is designed to ensure cancellation of torque fluctuation. The inner casing 8 has slots 3; each contains double sliding vanes 10 where the feeding pressurized oil 5 is used to stress them on outer casing 9 and the rotor 1 in order to avoid leak of the transmission oil 6. This configuration allows transmission of high load without any increase in the dimensions or pressure. Furthermore, it diminishes any torque fluctuation while having small number of double sliding vanes 10 (four double sliding vanes may be used).

In another case, Fig. 2, the rotor 1 and the outer casing 9 are two different pieces and therefore, this coupling provides two outputs. In such case, it is recommended to increase the number of double sliding vanes 10 to diminish fluctuations in torque transfer. The double sliding vanes 10 are stressing to the outer casing 9 and the rotor 1 with same force. This force may be, to a certain extent, excessive on one of the output members that provides smaller power.

Hence, different outputs require different forces needed to suppress slippage. Under this consideration, another configuration is introduced, Fig. 3. The inner casing 8 has two slot sets 3; one of them has its sliding vanes 4 stressing on the outer casing 9 while the other slot set 3 has its sliding vanes 4 forcing on the rotor 1 through feeding pressurized oil 5. Another dual output vane coupling is illustrated in Fig. 4. The rotor 1 presents the input while the inner casing 8 and the outer casing 9 present the outputs. The inner casing 8 then acts as a receiver of power from the rotor 1 and as a transmitter to the outer casing 9. Thusly, the inner casing 8 in any condition has same spinning speed or greater than the speed of the outer casing 9.

Vane coupling when used in geartrains it is required to transmit extremely high loads for various transmissions and power transfer mechanisms. Such load transmitted through the coupling is proportional to the applied twisting force. This force equals the build-up pressure times the net radial projected area. This area is the difference of radial projected areas of all the pressure side surfaces in the direction of rotating and that in the opposite direction. Thus, the torque capacity depends mainly on the dimensions of the coupling, its geometry and the operating pressure. For a demand of transmitting huge capacity, doubling the dimensions or two twice the operating build-up pressure leads to an increase of four times the coupling transmitted torque. Vane coupling having two casing 8 and 9, Fig. 2 or 3, with Dimensions less than 0.2 m outer diameter and 0.1 m coupling width offers radial projected area of 100 centimeter square.

The vane coupling can operate at extreme pressure conditions (150-200 bar). Operating with build-up pressure of 10 bar and radial projected area of 100 square centimeter can transmit high ranges a torque of 1000 N-m. This value is remarkably great where 800N-misthe maximum input of high power transmission that could be easily transmitted through this coupling. In addition, branching the power aids the increase torque capacity of the transmission

as well as it helps in operating the coupling with small applied torque so lifetime is intensely increased.

Multi-output vane coupling can be achieved by bypassing part of the input power to the coupling, the coupling has extra casing (s) (Figs. 2,3 and 4), and/or using combination of two or more vane couplings in such way that one, two or even more members are being shared. The significant aspect of different vane coupling configurations, Figs. 1,2,3 and 4, is that the vane coupling offers a reversible power transfer in both rotation speed and input and output power.

This feature leads dual and multi-output couplings to combine power.

Dual and multi-output vane couplings achieve power splitting and result in different power outputs that could vary continuously. This particular case can find itself in many power mechanisms that need more than one output. For example, the differential unit and the various cutting tool machines as well as many applications require two or multiple power outputs with different characteristics. The source of power for this unit may be electric motor, manual transmission, automatic transmission,... etc. Planetary set may be attached to outputs of the vane coupling to provide controlled differential spinning velocity to its two outputs. This kind of arrangement could be utilized as a vehicle differential unit.

Planetary Sets With Vane Couplings CPSCT Class To provide specific examples of how this class operates and controlled, two kinds of configurations for high and huge power capacities will be described and illustrated in following paragraphs. These two configurations differ in the number of the power splitting.

This unique arrangement is illustrated in Fig. 5. The floating planetary set 11 (power splitter) has one-input power directed from the engine, which is the input carrier 12. The two outputs of this set are the floating sun gear 13 and floating ring gear 14. The inputs to the output planetary set 15 (power combiner) are the ring gear 16 and the sun gear 17 which are attached to the floating sun gear 13 and floating ring gear 14, respectively where two vane couplings 18 are placed in-between their attachments. Each of the two ring gears 14 and 16 has extemal teeth 19 meshing with ordinary gears 20 for making this mechanical attachment between the two planetary sets 11 and 15. The output of the output planetary set 15 is the output carrier 21 that is attached to the shifting set 22. This set 22 that provides forward, neural, reverse and park drive modes. It contains forward gear 23 and rear gear 24. Two synchronizer clutches 25 and 26 are used for this set; the first clutch 25 is placed between forward gear 23 and rear gear 24 for different driving modes while the second clutch 26 is used to achieve park mode when engaged to the transmission housing 27.

The floating sun gear 13 and the input carrier 12 are attached to vane coupling that is

nominated as engaging and overrunning coupling 28. It is used to lock them together at starting of power flow and releasing them after that. Locking the floating sun gear 13 and the input carrier 12 offers them same rotation speed that is different from that of the sun gear 17 and ring gear 16. The load exerted on this coupling is extremely insignificant if the floating sun gear 13 and floating ring gear 14 have nearly same applied torque during starting.

Power is split flows into two paths that are the outputs of floating planetary set 11. Torque in each path is regulated by the vane coupling 18, which is attached to that path. Every path has definite speed corresponding to definite controlled torque. Hence, the configuration of the geartrain with the vane couplings 18 achieves controlled power that flows to the inputs of the output planetary set 15. Finally, the two paths of power combine in the output carrier 21.

In order to enhance the operation for huge power capacities (over 1000 horsepower), three power paths and only two vane couplings 18 are utilized for torque regulation. The splitting path concept for more than two branches will increase the torque capacity of the geartrain. The two vane couplings 18 will not regulate the torque in the third path if there is a need to progress the torque in the two power paths that contain the vane couplings 18. In order to overcome this, one of the vane couplings 18 operates with decreasing, fixing, or progressing torque capacity while the other coupling 18 decreases its transfer load during shifting. Therefore, regulation is accomplished in such a way that two of the power paths are controlled by the vane couplings 18 while the third one is controlled dependently.

This configuration is illustrated in the Fig. 6. All components of the first configuration are used besides, another planetary set is utilized. This planetary set is nominated as the intermediate planetary set 29. Power flows in three paths. The first and second power paths where power flows in the input planetary set 11 and the intermediate set 29 are likewise to that of the input planetary set 11 and the output set 15 of the first configuration. Power flows in the third path from the floating ring gear 14 to the ring gear 16 by means of ordinary gears 20. The first two paths combine in the intermediate planetary set 29 forming an output that combines with the third path in the output carrier.

Referring to Figs. 5 and 6, the operational concept of the two configurations as well as the purpose of the shifting set 22 is the same. Therefore, the description of the following paragraphs deals with operational concept of this class. Furthermore, illustration of discrete shifts is also included.

Drive range is used for all normal-driving conditions. The synchronous clutch 25 is activated to engage the forward gear 23 so power is transmitted to the vehicle wheels and the vehicle is driven to the forward direction. Power flows through the planetary sets 11 and 15 as the speed and torque is regulated.

Instantly before activating the synchronizer clutch 25, the two vane couplings 18 attached to the power paths are idling. The engaging and overrunning coupling 28 is locked and consequently the floating sun gear 13 and floating ring gear 14 rotate with equal speed. At the instance of selecting the drive mode, the synchronizer clutch 25 is activated thus, fixing the output carrier 21 because the vehicle is still stalled. The rotational speeds of the floating sun gear 13 and floating ring gear 14 are still the same while the sun gear 17 and ring gear 16 attached to the outputs of the vane couplings 18 spin with definite speed ratio. At this condition, the two outputs of two vane couplings 18 rotate with less speed than their inputs or at least one of them while the other has its same input speed. No power is transferred from the engine because of the two vane coupling 18 are not locked.

Gradual loading of the two fully non-locking vane couplings 18 at the instant of progressive idling the engaging and overrunning coupling 28 results in altering the given speed inputs to the output planetary set 15. This leads to rotate the output carrier 21 therefore; permitting vehicle movement while admitting higher output torque and minimum velocity. Hence, smooth starting can be obtained because of adequate time to transmit the demand torque. During various driving conditions, the engaging and overrunning coupling 28 is kept idled and its using and significance appears only at the starting instance in order to start power flow.

Meeting various transmission requirements is provided by addition torque or speed. This is accomplished by decreasing the building-up pressure inside one of the vane couplings 18 (non- locking mode) while increasing or keeping constant that inside the other 18 (locking mode). This may takes small instance of order of few tens of revelations with very small relative spinning between the input and the output of the coupling 18. One of the couplings 18 will be capable to handle more torque if the torque in other path (excluding the third power path in the second configuration) is decreased. In some cases as this depends on the road requirements like declination or due to certain type of control strategy, decrease of the torque capacity may be performed in the two couplings 18. Furthermore, the two couplings 18 may operates all the time in the locking mode and alteration of the transmission ratio is done by the change of the speed and torque of the output carrier 21 as a result of the road conditions.

By using any way to regulate torque, spinning of the members attached to each of the couplings 18 will be altered due to the change of the applied torque on it. The member that gives higher reduction ratio to the transmission is applied on it more torque for transmission reduction and less torque for acceleration. Also the member that gives lower reduction ratio to the transmission is applied more torque for acceleration and less torque for retardation.

The neutral mode enables the engine to operate without driving the vehicle. No power is transferred through the vane couplings 18 because of no build-up pressure inside them.

Moreover, the synchronizer clutches 25 and 26 are not activated. The reverse mode enables the power flow typically like that in the drive position but the main difference that the synchronous clutch 25 is activated to engage the rear gear 24 and keeps the forward gear 23 idling. The park mode is selected when the synchronous clutch 26 is activated to lock the transmission with its housing 27. This will stall the vehicle. In this case, the two vane couplings 18 are left idling and no power flows through the transmission.

Changing the build-up pressure in the vane couplings 18 leads to alteration of their torque capacities and results in transmitting a particular transmission output. Consequentially, four or even more selected oil pressures inside the vane couplings 18 are used to obtain their correspondents of gear ratios. Consequently, this transmission can be used for discrete gear ratios and acts as a manual transmission. This is an advantage to have a transmission operates as a manual and CVT mode. Moreover, this can be used for higher power demand when the driver selects manual shifts while this transmission operates in CVT mode.

Referring to Figs. 6 and 7, planetary sets 11 and 15, and 11,15 and 29 with vane couplings 18 arrangements establish a class having enhanced and superior performance. This is featured from the dependency of the operational performance of the planetary set 11,15 and 29 and the vane coupling 18. This class provides a reversible power transfer in both rotational speed directions as well as a reversed input and output power direction. The operational mode of the coupling 18 to be non-locked takes partial of second and has small relative spinning between the coupling 18 input and output. Therefore, enhanced operational feature, extremely high geartrain efficiency and long lifetime are provided as well as high speed requirement is fulfilled.

The two configurations of this class provide wide range of transmission ratios covering the reduction ratio needed for vehicle starting to overdrive transmission ratio. The directional spinning of all the members of each planetary set are the same. This is not necessary but is arranged so to avoid any torque cancellation especially in the output planetary set. The first configuration is suitable for medium and high power transmission, but the second configuration suits better for huge power transfer with efficient performance.

Conventional CVTs CPSCT Class The two configurations of this class that are utilizing the whole unit of belt-type CVT provide demonstrative examples of one kind of CVT and illustrate that other CVTs could operate using the same idea. One of the two demonstrative examples of this contribution is presented in Fig.

7. The configuration consists mainly of whole unit of bel-type CVT 30, output planetary set 15, vane couplings 18, ordinary gears 20 and 35. Vane couplings 18 and ordinary gears 20 could be located after or before the pulleys 31 and 32. Power flows in the first path through the input shaft 33 to the pulley 31 and transmitted by the belt 34 to the pulley 32. Vane coupling 18

attached to this pulley 32 is used to regulate the torque transmitted to the sun gear 17. In the second path, power flows through the pulley 31 to vane coupling 18 then transmitted to the ordinary gears 20 and 35 then to the ordinary gear 20 and finally passes to the sun gear 17.

While in the third path, power transfers through the pulley 31 to ordinary gears 20 and 35 to the ring gear 16. Finally, power paths combine in the output carrier 21. The ordinary gears 35 are used to perform same spinning direction to all the members of the output planetary set.

As mentioned before the main purpose of the vane coupling 18 attached to the pulley 32 is to avoid CVT shuddering while the other coupling 18 attached to the ordinary gears 20 is used to provide optional extra optional power path when it is loaded. The two vane couplings 18 may be used to bypass some or most of the power passing through the belt 34 at load pulsation conditions. Therefore, the two couplings 18 increase the longevity of the transmission. Other couplings or frictional or mechanical clutches may be used instead of these couplings 18.

For more decreasing the dependence of the belt 34 to transmit power, floating planetary set 11 and ordinary gear 35 are attached to the configuration, Fig 8. This arrangement provides optional three or four power paths. The three paths are mentioned before. The fourth path, power transmitted through the floating ring gear 14 by its extemal teeth 19 to the ordinary gears 20 then to the belt pulley 32. This arrangement admits the belt 34 as a power controller.

Referring to Figs. 7 and 8, this class offers reversible power flow in both rotation directions and in the directional input and output power flow. The first configuration makes the power transmission controlled by the belt 33 that represents the whole unit of CVT 30 (or any other CVT unit) and the output planetary set 15. This concept decreases the size of the belt 34 and the pulleys 31 and 32 thus, offering compactness, lightweight, high performance and low cost.

The second configuration has less dependence on the belt than the first configuration therefore, promising intensely more longevity and reliability for various power classes; low, medium and high.

Torque Converter CPSCT Class Figure 9 presents an illustrative example of this class that consists mainly of torque converter 36, two planetary sets which are reaction planetary set 37 and output planetary set 15, and the shifting set 22. The torque converter 36 is implemented in such way that the turbine 38 and the converter casing 39 (engine) that are two outputs of the torque converter 36 are two inputs to the two planetary sets 37 and 15 that have a common carrier 40. The reaction planetary set 37 has its ring gear 16 fixed and its sun gear 17 is attached to the turbine 38. The output planetary set 15 has its sun gear 17 mechanically engaged to the converter casing 39 and its output ring gear 41 attached to the shifting set 22 through external teeth 19. Selection of the different gear ratio of the shifting set 22 and that of the two planetary sets 37 and 15 cover the range of

transmission ratios needed for different road conditions.

In order to extend the operation range, discrete shifting geartrain with three, four or may be more different forward gears with different transmission ratio could replace the shifting set 22. In this case, no planetary sets are used and the torque converter may be used as power controller only where its turbine is attached directly to the discrete shifting geartrain. Furthermore, torque converter used as power controller may be utilized in the conventional automatic transmission and different CVTs. Bypassing oil control is used specially during discrete shifting. Power controlling may be utilized using vane coupling attached to the turbine instead of the bypassing oil control. In such case, the input of the coupling is connected to the turbine. In such case, the vane coupling is placed in-between the turbine and the transmission.

Bypassing certain amount of oil from the turbine 38 regulates the power characteristics in each path. The transmission is idled when no oil or small amount of it is fed to the turbine 38. At the instant of selecting drive or reverse mode, gradual loading the torque converter 36 leads power to flow in the two paths which are the inputs of the two planetary sets 37 and 15, and finally combined in the output ring gear 41. The operational selected range of torque converter 36 is depending on the planetary arrangement. Progressing of the torque or speed rely on the load applied on the turbine 38 and the converter casing 39 that vary according to the road requirements while engine speed is fixed. Enhanced sort of operation and sometimes demanding of more power could be done by the compromising the optimum beneficial characteristics of the engine speed and relative spinning between engine speed and the turbine 38. Controlling the torque converter 36 that is represented by bypassing the oil may be replaced by using the vane coupling 18 attached in-between the turbine 38 and the sun gear 17 of the reaction planetary set 37.

This class presents substantial improvement of the automatic transmission that is overviewed from compromising the optimum operating speed range of the turbine with the engine speed as well as not utilizing of the clutches and bands like that of the automatic transmission. Few components that are conventional parts form this transmission and achieve lightweight and less production expenses. Besides, the less dependency of the torque converter results in higher performance, smaller torque converter and the geartrain compactness.

Controlled Power Splitting Vane Coupling Class Figure 10 illustrates an example of this class. The arrangement showed in the figure consists mainly of two vane couplings; dual output vane coupling 42 (controlled power splitter), Fig. 2 or Fig. 3, and dual input vane coupling 43 (controlled power combiner) that represents new stepless mechanism, same two referring figures. The dual input vane coupling can be replaced by a differential unit. Low to medium power capacity could be transferred by such class.

Compactness feature and reduction of parts are achieved over the other classes putting it as special demanding purposes of lightweight and size. In this arrangement vane coupling represented in Fig. 4 could be used where, as mentioned before, its outer casing 9 is always has either equal or less speed than its inner casing 8.

Extensional Classes The configuration shown in Fig. 11 illustrates an example of this class where blending of two classes develops other class having different features. Belt type CVT as an example of any type of CVT is attached to torque converter 36 that acts as controlled power splitter. As shown in Fig.

11, part of power passes through the converter casing 39 to the whole belt-type CVT unit 30 while the other part is transmitted through the turbine 38. Vane coupling 18 is used to systemize the maximum torque transmitted by the belt 34.

Developmental Class This class is demonstrated by placing any power transfer mechanism in one of the power paths of the previous classes, Figs. 5 through 11, to utilize it as controller, or using it as controlled power splitter or controlled power combiner. Eample of this class is illustrated when placing any CVT unit instead of the vane coupling 18, Fig. 5, in one power branch.

While the invention has been particutarly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. Furthermore, the contributions, notions, conceptions of this invention are not only concemed with the presented description but also deals with any subject that considers any of the description aspects.