Patent Application
20100012409
The invention herein resides in the art of hybrid vehicles, particularly of the type adapted for implementation of alternate drive sources. Particularly, the invention relates to a module including an electric drive motor adapted for selective interconnection with the drive shaft of a vehicle to alternatingly provide an electric motor or heat engine as the power source for the vehicle drive mechanism. Specifically the invention relates to a post transmission hybrid drive module having parallel motor and output shafts, the output shaft being interconnected with the drive shaft of a vehicle and the motor shaft being selectively engageable with the output shaft.
The invention further relates to uniquely configured and optimally controlled series/parallel hybrid drive modules for vehicles that allow for ease of shifting between power sources and outputs, consistent with maximizing the efficiency of the operation of the vehicle. Specifically, the invention relates to a series/parallel hybrid drive module for vehicles, uniquely adapted for implementation with heat engines and motor generator assemblies, and having a unique segmented input/output shaft with associated gears and shift mechanisms to ensure smooth and effective operation between various input sources and output loads. The invention is adapted for implementation with commercial, military, construction and agricultural equipment, and particularly relates to vehicles of all types, including electric, fuel cell, and hybrid vehicles having significant electrical energy storage that can operate for extended periods on electricity alone.
The cost of fuel for the engines typically employed for driving vehicles has given rise to an acute need for alternative fuels or hybrid vehicles, adapted for implementation of various fuel sources. Presently, the most advantageous type of an alternate fuel vehicle is the hybrid vehicle, which, in its most common sense, employs a diesel or gas powered engine and an electric motor as alternative power sources. Prior attempts to achieve this combination have generally met with disappointment, being either excessively costly or under powered in providing motive force. Moreover, the packaging of alternative power sources has been given to complexities that have yet to be overcome, resulting in vehicles that are not only costly, but given to service and maintenance problems. Moreover, presently known electric motors and their methods of implementation have been fraught with power output that is inconsistent with the bulk, size, weight and cost of the motor being implemented.
The instant invention provides a module for use with electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles and other applications requiring high performance, light weight, and economical electric motors and/or generators. It is known that the alternating current (AC) induction motor is the simplest and least expensive type of electric motor for vehicle traction drives. The advent of Flux Vector inverter drive controls provides for variable frequency control up to very high speeds for standard induction motors. Standard motors are typically wound for the common 60 hertz frequency that is used in the United States, or 50 hertz, which is used for the most part in the remainder of the world. High frequency motor invertor drives can operate into the range of 200 to 400 hertz, resulting in motor speeds up to 12,000 rpm for common four pole motors that normally run at 1,800 rpm. A properly matched controller and high speed motor can produce 3 to 5 times the peak power from a similarly sized standard AC induction motor. Further, with effective cooling such a motor can produce 5-10 times the continuous power rating of a standard fan cooled motor and even well beyond that of water jacket cooled motors. Particularly problematic is the need for removal of the heat in the rotor core and stator windings to achieve high continuous power.
It is well known that an AC induction motor commonly uses a “squirrel cage” rotor as its only rotating part. In overall shape, the rotor is a cylinder mounted on a shaft. Internally, it contains axial or longitudinal conductive bars of aluminum or copper set in grooves or holes in the rotor laminations and connected at both ends by shorting rings of aluminum or copper to form a cage-like conductive structure. The core of the rotor is built up of a stack of iron laminations. The field winding in the stator of an induction motor sets up a rotating magnetic field around the rotor. The relative motion between this field and the rotation of the rotor induces electric current flow in the conductive bars. In turn, these currents flowing lengthwise in the conductors react with the magnetic field of the motor stator windings to produce a force acting at a tangent to the rotor, resulting in torque to turn the motor shaft. In effect, the rotor is carried around with a magnetic field, but at a slightly slower rate of rotation. The difference in speed is called “slip” and increases with load.
Motor vehicles employing hybrid drive systems to drive the vehicle are well known in the art. Typically, the hybrid power train system is either a series or parallel hybrid configuration. In general, a series hybrid configuration includes a heat engine, an electric generator, an electricity energy storage and management system, a traction electric motor, and final drive unit, all functionally connected in series to move the vehicle without direct mechanical connection. The series hybrid configuration is more efficient for urban driving, but suffers from the disadvantage of being less efficient for highway driving, in that it has the inherent losses in the motor/generator that is less efficient than a highly efficient “manual” or automated manual transmission.
Typically, a parallel hybrid configuration includes a heat engine, one or more electric generators that also function as traction motors, a transmission with electric motor/generators either before or after (pre or post) the transmission, an electricity energy storage and management system, and a final drive unit. These components are managed such that there exists functionally parallel and independent paths from the heat engine and the propulsion motor to move the vehicles. The parallel hybrid configuration is more efficient for highway driving and many specialty vehicle needs, such as acceleration, deceleration, and hill climbing, to name a few. However, the parallel hybrid tends to suffer a disadvantage of being less efficient for urban driving.
There are various configurations of hybrid drives that combine electric motors in planetary transmission arrangements. Such drives combine series and parallel capabilities using planetary gearing, but suffer from electric motors that must operate at slower speeds that hinder their maximum power capability. Further, these configurations generally utilize multiple disk friction clutches that detract from the overall transmission efficiency when one or more of these clutches are disengaged. Multiple disk wet clutches, such as used in automatic transmissions, are very inefficient when they are idling due to the fluid dynamic drag torque inherent in the disks with oil flowing through them. Thus, there is a trend toward “dual clutch” transmissions where only friction clutches provide alternating smooth shifting in an automated manual transmission. But, even these are less efficient than a “manual” transmission. In addition, planetary geared series/parallel hybrids require very expensive tooling in high production quantities, which can preclude their general use in lower volume commercial, construction, and military vehicles.
There is a need in the art for a simple, cost effective and reliable series/parallel hybrid drive module for vehicles that allows for optimization of use of various power sources, including by way of example but not limitation, heat engines and electric motors. It is particularly desirable that shift and select mechanisms are provided in association with the power train to ensure optimum selectability between various power sources and output loads, allowing the vehicle to operate efficiently at highway speeds, slow urban speeds, when negotiating hills, when operating at idle or in “hotel” mode, or when simply operating as a generator for exportable electric power, or to restore the battery power source for electric operation.
In light of the foregoing, it is a first aspect of the invention to provide a new and improved hybrid power train system for vehicles with heat engines, which employs features of both series and parallel hybrid configurations.
Another aspect of the invention is the provision for a drive system that can operate in either series or parallel hybrid configurations.
Still a further aspect of the intention is to provide a drive system that can utilize the engine and both an input side and output side hybrid motor in parallel with the engine for maximum power needs of the vehicle.
Still a further aspect of the invention is the provision of a drive system that allows significant downsizing of the vehicle engine to maximize fuel economy.
Another aspect of the invention is the provision of a drive system employing an oil cooled electric drive module or modules that can significantly reduce the weight and cost of electric motors for vehicle traction drives.
An additional aspect of the invention is the provision of a drive system that accommodates powering various accessory systems of a motor vehicle from the hybrid power train system.
Yet another aspect of the invention is the provision of a drive system that includes the ability to export power from either one or both of a pair of motor generators and an associated energy storage system, while the vehicle is stationary.
A further aspect of the invention is to provide a drive system that may allow the engine to recharge the battery when the vehicle is stationary.
Another aspect of the invention is to provide a drive system that accommodates packaging of the motor-generator and related gearing, clutches and actuators in the area normally used for a conventional transmission in the vehicle.
It is still a further aspect of the invention to provide a drive system having a sufficient number of automatically shifted manual gear sets to allow the engine to aid in vehicle acceleration, and to efficiently provide the sole means of the vehicle propulsion for all speeds above a given threshold.
An additional aspect of the invention is the provision of a vehicle drive system that eliminates the inefficiency of idling multiple disk wet friction clutches from the drive system, particularly when the engine is operating.
Another aspect of the invention is to provide a hybrid power train drive system that employs automated rapid shifting of the manual gear changes to minimize power interruption during shifting.
An additional aspect of the invention is the provision of a hybrid power train drive system having multiple electric motors, and in which at least one of the electric motors can always be engaged to the driven wheels during gear shifting.
Another aspect of the invention is the provision of a hybrid power train drive system in which an electric motor that is driving during shifting provides a maximized torque momentarily to maintain smooth acceleration during shifting.
Still a further aspect of the invention is the provision of an improved hybrid power train system that allows for acceptable vehicle operation even in the absence of operation of electric motors/generators.
Still another aspect of the invention is to provide an improved power train system that may be used in battery powered electric vehicles or fuel cell powered vehicles having the foregoing advantages, but without the need of a heat engine, and provide improved drive system efficiency with zero emissions.
Yet a further aspect of the invention is to provide a hybrid power train drive system that includes a selectable drive for hydraulic pumps or other auxiliary devices that can be selectively powered by the heat engine or an electric motor/generator.
Yet another aspect of the invention is the provision of a hybrid power train system having a selectable auxiliary drive for hydraulic motor/pump operation, and with an energy storage accumulator to selectively provide a hydraulic power boost, thus creating the opportunity for power drive by heat engine, electric motor, or hydraulic motor.
A further aspect of the invention is the provision of a post-transmission parallel hybrid power train module that has two or more speed capabilities between an electric motor and the vehicle output to provide higher torque and acceleration at low speeds while allowing the motor to match torque requirements at intermediate or high speeds.
Yet an additional aspect of the invention is the provision of a post-transmission parallel hybrid power train module that includes an input disconnect to allow an electric motor to power the vehicle without the engine and transmission running.
Still a further aspect of the invention is the provision of a post-transmission parallel hybrid power train module that includes an output disconnect to allow the engine to drive an electric motor as a generator to recharge the vehicle battery with the vehicle stationary, and to provide exportable power for other uses.
Another aspect of the invention is the provision of a post-transmission parallel hybrid power train module that provides direct drive between a main power source and output to achieve the highest engine drive efficiency when the vehicle is operating at highway speeds.
Another aspect of the invention is to provide a post-transmission parallel hybrid power train module that includes an auxiliary low-speed transmission with multiple speed capabilities to accommodate movement when extremely low speeds or high torque are required.
The foregoing and other aspects of the invention that will become apparent as the detailed description proceeds are achieved by a post-transmission parallel hybrid drive module for a vehicle, comprising: an AC induction motor having a motor shaft extending therethrough, said motor shaft having a rotor attached thereto, said rotor being received within an array of stator windings, and said motor receiving cooling oil over opposite ends of said rotor and onto said stator windings; a sump adjacent said motor for receiving cooling oil from said windings; an input and an output shaft adapted at opposite ends thereof for interposition within a drive shaft of a vehicle; a gear assembly interposed between said motor shaft and output shaft for selective driving engagement therebetween; and a selective disconnect between said input and output shafts.
Other aspects of the invention are achieved by a hybrid drive module for vehicles, comprising: a motor having a motor shaft; an output shaft adapted at opposite ends thereof for interposition within a drive shaft of a vehicle, said drive shaft having an input shaft portion and a remaining portion; a first gear assembly interposed between said motor shaft and output shaft; a first shift assembly interposed with said first gear assembly for effecting selective driving engagement between said motor shaft and output shaft; and a second shift assembly interposed between said input shaft portion and and said remaining portion for selective driving engagement between said portions.
Still additional aspects of the invention are achieved by a multiple electric motor/generator drive system for vehicular propulsion, comprising: a first motor/generator operatively positioned at, and offset from, an input of a multiple speed actuator controlled gearing system; and a second motor/generator operatively positioned at, and offset from, a point of said multiple speed actuator controlled gearing system beyond said first motor/generator and toward an output thereof.
For a complete understanding of the various aspects of the invention, along with the structure and method of operation associated therewith, reference should be made to the following detailed description and accompanying drawings wherein:
Referring now to the drawings and more particularly
Received within the housing 12, comprising halves 12a and 12b, is a drive shaft or output shaft 18, having respective ends 18a, 18b adapted for interconnection with the drive shaft of a vehicle. In other words, the drive shaft 18 is adapted to be interposed within the drive shaft of the vehicle, beyond the vehicle's transmission, and interconnected therewith through universal joints or the like at 18a and 18b. Also received within the housing 12 and maintained in parallel relationship to the drive shaft 18, is a motor shaft 20 of a motor having a squirrel cage configuration. The motor includes a stator core 22 having stator windings 24 thereabout in standard fashion, the stator core and windings being fixedly retained in the housing 12. A rotor base 26, of standard fashion, is connected to the motor shaft 20 and is rotatable therewith. In standard fashion, conducive bars 28 extend axially across the rotor base 22 and are interconnected as by shorting rings 30 at the lateral ends thereof.
Appropriate bearings 32 are provided at opposite ends of the motor shaft 20 for rotational support. A speed sensing bearing 34, appropriately encoded or otherwise graduated for producing signals corresponding to rotational speed, is provided at one end of the motor shaft 20. At the opposite end, an oil distribution ring assembly or rotary union is attached to the motor shaft 20 and is provide in communication with an axial bore 38 extending thereinto. The axial bore 38 extends to and communicates with a radial bore 40 that extends outwardly into communication with the outer circumferential surface of the motor shaft 20. A plurality of axial splines or reliefs 42 are provided in the circumferential surface of the motor shaft 20 and extend between end rings 44, provided at each end of the rotor base. The end rings 44 are in the form of annular disks, washers, deflectors or the like. This structure and arrangement provides an important pathway for cooling oil to enter the motor shaft 20 at the oil distribution ring or rotary union 36, to pass through the axial bore 38, outwardly through the radial bore 40, and into the space between the shaft 20 and rotor base 26. The plurality of axial splines or reliefs 42 provided in the circumferential surface of the shaft 20 direct the cooling oil outwardly between the shaft and rotor base to the end rings 44, where the cooling oil is redirected radially by such deflectors at the end of the rotor. There, the cooling oil is centrifugally spun outwardly with a coanda effect that coats the aluminum or copper shorting rings 30 on the end faces of the rotor. This oil is centrifugally thrown off of the rotor directly into the stator windings 24 to then flow downwardly through the motor to drain holes 46 in the aluminum housing 12 and into a recovery and recirculating sump 48, that receives the drive shaft 18. A drain 50 is provided within the sump 48 to return the cooling oil to an appropriate pump, auxiliary heat exchanger, or the like for redistribution back through the assembly 10 or other units associated with the vehicle.
The invention employs a gear reduction set between the motor shaft 20 and output shaft 18 to tailor the motor speed to a desired output speed. In one embodiment, the gear set includes a first stage helical gear 52 in driving connection through gear teeth with the motor shaft 20. Those skilled in the art will understand that the first stage helical gear 52 is connected through an appropriate gear drive shaft ( shown in
The mechanical disconnect mechanism 56 is operatively connected to a splined collar 58 that is interposed between the second stage helical gear 54 and the output shaft 18. The collar 58 is axially slidable with regard to both the output shaft 18 and gear 54 to selectively engage and disengage the two. An actuator arm 60 is interconnected with the mechanical disconnect mechanism 56 and driven by a hydraulic piston 62 upon a slide 76, as shown. The piston 62 is received by a hydraulic cylinder 64, having dual cavities to both extend and retract the piston 64 with respect thereto. Accordingly, the piston 62 is capable of engaging and disengaging the collar 58 through the disconnect mechanism 56 and associated actuator arm 60. A solenoid valve 66 is electrically operated to selectively actuate the piston 64 in either the engage or disengage direction.
As shown in
In use, it will be appreciated that the solenoid valves 66 may be employed to selectively engage/disengage the motor drive from the output shaft 18. The timing of the engagement/disengagement is achieved by correlation of the outputs of the speed sensing bearings 34, 70. When disengaged, the output shaft 18 is driven solely by the heat engine of the vehicle. When engaged, the motor drive mechanism either provides sole power to the vehicle (in which case the heat engines are disengaged from the output shaft 18) or the motor is used to supplement that power. Of key importance is the ability to provide an AC motor structure that can be effectively cooled in order to ensure optimum efficiency in a small, light weight, cost effective envelope. The provision of an oil distribution ring assembly or rotary union 36 in association with axial and radial bores 38,40, coupled with the implementation of axial splines or reliefs 42 and end ring deflectors 44 to provide a coanda sheeting of cooling oil across the end surface of the rotor which is then centrifugally spun outwardly onto the stator of the motor, and its housing, providing for effective cooling that optimizes motor performance.
As shown in
A pair of permanent holding magnets 102, 104 is employed to hold the actuator arm 60 in a desired position, once moved by the piston 62. Accordingly, the piston, cylinders, and solenoid valve 66 are employed to move the actuator arm 60 to either engage or disengage the output shaft 18 with the second stage gear 54, and the actuator arm 60 is then maintained in that position by an appropriate holding magnet 102, 104 such that the hydraulic pressure can be released, and not reapplied until opposite shifting is desired. In that regard, proximity sensors 106, 108 are provided in association with the actuator arm 60 or other associated movable element, to sense that the desired shifting has occurred and then signal through an appropriate control mechanism that the solenoid valves 66 can be released for removal of the hydraulic pressure.
The instant invention further contemplates that an auxiliary heat exchanger 110 may be interposed between the pressure relief valve 94 and the sump 48 for further cooling efficiency. The heat exchanger 110 may be of any suitable nature, such as a radiator, finned housing, cooling jacket or the like. The necessity of transferring heat from the motor assembly to the ambient is of primary importance to ensure optimum effective operation of the motor. In keeping with such efforts to maximize and optimize cooling of the drive motor, it is further contemplated as a portion of the cooling oil recirculation that the output of the pump 90 or heat exchanger 110 might also provide additional cooling to the stator core 22 and windings 24. To that end, as shown in
Referring now to
The input side module 122 includes an input secondary shaft 132 adapted for selective interconnection with the input shaft 126 and intermediate shaft 128. In similar fashion, the output module 124 includes an output secondary shaft 134 adapted for selective interconnection with the intermediate shaft 128 and output shaft 130.
The input module 122 includes a motor/generator 136 and, in like fashion, the output module 124 includes a motor/generator 138. Those skilled in the art will readily appreciate that a motor/generator selectively operates as either a motor, receiving an electrical input and converting it to a mechanical output, or as a generator, in which a mechanical input is converted to an electrical output. The motor/generator contemplated for use herein may be of various types as would be appreciated by those skilled in the art, but is preferably of the oil cooled electric drive module type as presented and described above. The mechanical inputs and outputs of the motor/generators 136, 138 connect through the respective shaft 132, 134 as selectively interconnected with the shafts 126,130 as will be discussed below. The shafts are all rotatable upon appropriate bearing mount assemblies 140, as will be readily appreciated by those skilled in the art.
With continued reference to
The gears 142a, 144a, 146a are mounted upon the respective shafts 126, 128 and are freely rotatable thereon by means of associated bearings 150. These gears may, however, be selectively connected to and rotatable with the associated shaft 126, 128 by means of associated shift assemblies 152, 154. Those skilled in the art will appreciate that the shift assemblies 152, 154 are slidably received upon splines of the associated shafts 126, 128 for axial movement in association therewith and may be of any suitable nature known to those skilled in the art including, by way of example, dog clutches. Those skilled in the art will appreciate that dog-type clutches are preferred because they exhibit near-zero drag when disengaged. The shift assembly 152 may be shifted to the left as viewed in
It should further be appreciated that the gear ratio achieved between the shafts 126, 132 by means of the gears 142a, 142b, is typically different from the gear ratio between the gears 144a and 146b. Accordingly, the shift assembly 152 selects between two gear ratios for interconnection between the shafts 126, 132. The shift assembly 154 merely selects between interconnection between the shafts 126, 128 or interconnection between the shaft 128 and the shaft 132. It will be appreciated that the shafts 148 and 132 may be interconnected through gears 146b and 146c or, alternatively, an additional gear may be added to shaft 132 for making engagement with gear 146c if a different gear ratio is desired. With continuing reference to
The shift assembly 166 is adapted to selectively interconnect the intermediate shaft 128 with the output shaft 130 when actuated to the right as shown in
Those skilled in the art will appreciate that a module 120, comprising input and output modules 122, 124 and the segmented shaft 126, 128, 130 is capable of a multitude of geared interconnections and, accordingly, various modes of operation, as will be the discussed below. It should be noted that the only interconnection between the motor/generator assemblies 136, 138 is an electrical interconnection shown as 168 in
With reference now to
Urged against the body of the yoke 188 is a pair of oppositely disposed pins 190, 190a, each having a respective head 192, 192a on opposite ends thereof. Springs 194, 194a are maintained about the respective pins 190, 190a and are captured between washer 196, 196a at the end having the head 192, 192a thereon, and an assembly at the opposite end comprising piston seals 198, 198a sandwiched between respective washers 200, 200a and 202, 202a, and maintained upon the pin by respective keepers 204, 204a. Preferably, the springs 194, 194a are precompressed upon the respective pins 190, 190a.
It will be noted that the washers 196, 196a have respective inner circumferential partial notches 206, 206a therein and outer circumferential partial notches 208, 208a therein, for purposes that will become apparent herein.
Cylinders 210, 210a are defined within the cavity 184 to respectively receive piston assemblies 190-208 and 190a-208a, as shown. Each of the cylinders has a respective aperture for hydraulic fluid, serving both as a source and a drain of pressurized hydraulic fluid, designated by the numeral 212, 212a. Finally, it will be appreciated that the cylinders 210, 210a are characterized by stops 214, 214a adapted to engage the washers 196, 196a, and necked-down cylinder end portions 216, 216a for receiving respective heads 192, 192a of the pins 190, 190a as will become apparent herein.
The neutral state of the shift assembly 180 is shown in
The efficiency of the operation of the shift assemblies 180 is enhanced by the synchronization attained by the control circuit 220, shown in
The efficiency of the operation of the system of the invention is further enhanced by a gear shifting sequence that ensures that one of the motor/generators 136, 138 maintains driving power to the associated vehicle while gears associated with the other are shifted. Such efficient operation is further enhanced by the use of helical and/or spur gears mounted on parallel shafts and shifted by dog-type clutches slidable upon shafts.
With an appreciation of the structure of the elements of the invention, an understanding can now be obtained with regard to its operation and the multiple capabilities of the series/parallel hybrid drive module for vehicles presented above. As a start, it will be appreciated that the output side oil cooled electric drive module 124 may have a similar motor generator 138 and gearing as presented with regard to
The shift assembly 166 allows direct engagement of the intermediate shaft 128 to the output shaft 130. If the output side module 124 were to be used without the input side 122, intermediate shaft 128 would be the input shaft connecting it to the output of a vehicle's engine or transmission, or other appropriate power source. The shift assembly 166 can also selectively disengage the output shaft 130 and engage the gear mesh 160a, 160b to drive the motor generator assembly 138 for purposes of electrical energy generation from the heat engine.
Shift assembly 166 may also be placed in a neutral position to disengage the output shaft 130 and the motor generator assembly 138 from the intermediate shaft 128, and thus from the engine or other input power source. In the neutral position, the motor generator 138 is available to drive the output shaft 130, and the associated vehicle or other device, without heat engine operation or other power input.
As presented above, the input side oil cooled electric drive module 122 is substantially a mirror image of the module 124, although the gear mesh ratios may differ. The shift assembly 152 is operative to select between gear shift ratios 142a, 142b and 144a, 144b to cause the input shaft 126, preferably driven by a heat engine, to drive the input secondary shaft 132, which in turn drives the motor generator assembly 136 through the gear ratio 146b, 146c. Alternatively, the motor generator 136 may drive the input secondary shaft 132 through the gear mesh 146b, 146c and selectively drive the input shaft 126 through one of the engaged meshes 142a, 142b and 144a, 144b. It will be noted that the shift assembly 152 also has a neutral position, in which case the gears 142a, 144a are freewheeling on the input shaft 126.
Shift assembly 154 is adapted to selectively interengage the input shaft 126 with the intermediate shaft 128 through a direct connection at a 1:1 ratio. Alternatively, the shift assembly 154 may interconnect the input secondary shaft 132 to the intermediate shaft 128 and thereby gain two additional speed ratios from gear meshes 142a, 142b and 144a, 144b which may be selectively interconnected to the input secondary shaft 132.
Those skilled in the art should recognize that the output side module 124 may serve as an independent system adapted to join with an engine/transmission to provide a hybrid vehicle on its own. In like manner, the input side module 122 may be employed to replace the transmission on any engine for any vehicle without an output side module 124. The output side module 124 and the input side module 122 may find separate and independent use in various vehicles, or may be joined together as two independent units, such that with integrated control of the two units, a broad range of benefits can be obtained.
It will further be appreciated that the input secondary shaft 132 and output secondary shaft 134 may, in various employments, drive hydraulic pumps or otherwise power hydraulically actuated axillary equipment or, indeed, act as a hydraulic motor to aid in vehicle propulsion and acceleration, as the need may present itself.
Having considered the input side module 122 and output side module 124 separately, it will be appreciated that their operation in the total system 120 is in conjunction with a segmented drive shaft 126, 128, 130, as shown. It is contemplated as a portion of the invention that the segmented shaft, or portions thereof, may selectively drive or be driven by associated motor generators 136, 138 under control of the shift assemblies 152, 154, 164, 166, as described above. It is also contemplated that when employed in vehicle use, and particularly at highway speeds, the shift assemblies 154, 166 are shifted such that a direct interconnection is achieved between the input shaft 126 and intermediate shaft 128, as well as the intermediate shaft 128 and output shaft 130, all being made with a preferred 1:1 ratio. In this way, when the vehicle is operating at highway speeds, optimum efficiency of the heat engine can be enjoyed.
With further reference to the system of
The system 120 further allows the output module 124 to enable the electric motor of the motor generator 138 to power the vehicle without the associated heat engine and transmission running. The shift assembly 166 may simply disconnect the intermediate shaft 128 and the output shaft 130, allowing the output secondary shaft 134 to control operation of the output shaft 130 at a gear ratio selected by the shift assembly 164. This operation, being totally electric, is ideal for urban operation with no environmental emissions from the vehicle, or for use in stealth operations for military vehicles or the like.
The invention further contemplates a disconnect of the output shaft 130 from the intermediate shaft 128, allowing the heat engine to drive the motor generators 136, 138 through the intermediate shaft 128, to provide for electric power generation and recharging of the vehicle batteries without moving the vehicle, such as overnight stays of semi-tractor trailers, or to provide for exportable power for use by emergency and military vehicles and the like.
As presented above, disconnect of the input side module 122 and output side module 124 may be achieved with the system 120, allowing interconnection of the segments 126, 128, 130 of the shaft assembly of the invention, and thus a straight through drive to the heat engine when the associated vehicle is operating at highway speeds, or when the load on other drive equipment is minimized. Accordingly, the system 120 may completely disconnect the motor/generators of the modules 122, 124, eliminating the idling gears, and the associated losses common in multiple speed transmissions.
The system 120 further accommodates extremely low speed operation with multiple speed capability in order to provide for exceptionally low speeds with high operational torque. The various gear ratios achievable through selection of various shift assemblies 152, 154, 164, 166 allow the downsizing of the heat engine and a reduction in the number of speeds of the associated transmission in order to achieve the same operational capabilities. For example, where a truck required a 450 horsepower engine with an 18 speed transmission, with the implementation of a system comprising the output side module 124 in association with the heat engine of the truck, before or after its transmission, the engine size may be reduced from 450 horsepower to 300 horsepower, with the transmission being reduced from an 18 speed transmission to a 6 speed transmission. All of this may be achieved by simply adding a three speed output module 124, with 150 horsepower peak power. By replacing the truck transmission with system 120, with both motors 136, 138 at a peak of 150 horsepower, further economies may be enjoyed with a heat engine of less than 200 horsepower.
It will be readily appreciated by those skilled in the art that the system 10 may be readily packaged in the space saved by the reduction in necessary gearing and engine size of previously employed vehicles. Those skilled in the art will further appreciate that any of numerous combinations of employment of the motor generators 136, 138 at various gear ratios, with or without the assistance of each other, and with or without the assistance of the heat engine itself, may be employed to maximize operational efficiency, minimize pollutant emissions, reduce engine size and complexities, provide for electric power generation for auxiliary equipment, and provide for the generation of hydraulic power sources for the operation of auxiliary hydraulic equipment.
Thus it can be seen that the various aspects of the invention have been satisfied by the structure presented above. While in accordance with the patent statutes only the best known and preferred embodiment of the invention have been presented and described in detail, the invention is not limited thereto or thereby. Accordingly, for an appreciation of the true scope and breadth of the invention reference should be made to the following claims.
This is a continuation-in-part of copending application Ser. No. 12/218,593, filed Jul. 17, 2008, for Oil Cooled Electric Drive Module for Hybrid Vehicles.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12218593 | Jul 2008 | US |
| Child | 12363981 | US |
