Abstract: The apparatus of the present invention provides a stator for an electric motor. The apparatus includes a plurality of stator components assembled together to form a generally annular stator core. A wire is wrapped around at least a portion of the stator core to form a stator winding. A first generally annular end plate and a second generally annular end plate are mounted to axially opposite sides of the stator core such that the stator core is axially trapped and retained therebetween. A fastener applies a clamping load to the first and second end plates such that the stator core is compressed therebetween. The clamping load from the fastener is applied directly to the first and second end plates which distribute the clamping load to the stator core such that the plurality of components are held together without the fastener directly applying the clamping load to the stator core. A corresponding method for providing a stator is similarly provided.

Abstract: A hybrid transmission is provided with a motor and a torque-transfer device is operable to transfer torque from the motor to a transmission input member upstream in power flow from the transmission gearing arrangement. The torque transfer device may be a fluid coupling, such as a torque converter, including a torque converter lock-up clutch. In other embodiments, the torque transfer device is a launch clutch that may be either a wet clutch engagable via pressurized transmission fluid, or a dry clutch, such as used in a manual transmission. A disconnect clutch is selectively engagable to operatively connect an engine connection member with the motor to permit the motor to start the engine, such as after a stop. Many embodiments of the transmission include a one-way clutch arranged in parallel with the disconnect clutch. A method of starting the engine using such a transmission is also provided.

Abstract: A transmission has an input member and an output member, first and second intermediate shafts having substantially identical gear sets with gears concentric with and selectively connectable for rotation with the first and second intermediate shafts, respectively. Output gears are concentric with and rotatable with the output member and mesh with the substantially identical gear sets. First and second torque-transmitting devices are operable for transmitting torque from the input member to the first and second intermediate shafts, respectively. Torque-transmitting mechanisms are mounted concentric with, rotatable about and selectively engagable with the gears mounted on the intermediate shafts. A controller is operatively connected to the torque-transmitting mechanisms and to at least one of the torque-transmitting devices.

Abstract: The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including first, second and third differential gear sets, a battery, two electric machines serving interchangeably as motors or generators and four selectable torque-transfer devices. The selectable torque transmitting devices are engaged to yield an EVT with a continuously variable range of speeds (including reverse) and four mechanically fixed forward speed ratios. The torque transmitting devices and the first and second motor/generators are operable to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode.

Abstract: An electrically-variable transmission is provided with first and second motor/generators and three planetary gear sets. The planetary gear sets have continuous interconnections, and selective connections via a plurality of torque-transmitting mechanisms, that provide three forward electrically-variable modes. Preferably, the planetary gear sets are characterized by effective gear ratios such that a substantially equal maximum torque is required from each of the motor/generators during the three forward electrically-variable modes for a given torque on the input member. This allows the first and second motor/generators to be substantially equal in size.

Abstract: A stator assembly is provided for an electric motor having a longitudinal axis. The stator assembly includes at least one stator segment having a first end member having a stator tooth and at least one of a stator shoe and a back iron. A second end member is positioned with respect to the first end member and has a stator tooth and at least one of a stator shoe and a back iron. A winding generally circumscribes the stator tooth of the first end member and the stator tooth of the second end member. The first and second end members have a parting line generally perpendicular to the longitudinal axis of the motor. A motor incorporating the stator assembly of the present invention is disclosed. Additionally, a method of forming the stator assembly of the present invention is described.

Abstract: An electrically-variable transmission has four motive elements, including an input member, an output member, and first and second motor/generators. The transmission also has two differential gear sets, and four selectively engagable torque-transmitting mechanisms. All members of each differential gear set have at least one of the motive elements connectable therewith. The input member and one motor/generator are both connected or connectable with the same member of one of the differential gear sets, and the output member and either of the motor/generators are both connected or connectable with the same member of the other one of the differential gear sets. The torque-transmitting mechanisms are selectively engagable in combinations of two to establish input-split and output-split electrically-variable modes of operation.

Abstract: A delta type inverter is used in conjunction with a closed-loop motor controller to provide a control device for driving a three phase brushless direct current motor. The delta inverter has one-half of the solid state switching devices and diodes required by conventional bridge type inventers, thereby improved reliability, and enabling the motor control device to have reduced size, cost and weight. The closed-loop motor controller may include a torque loop for reducing torque ripple during operation of the motor.

Abstract: An electric torque converter has a torque converter input member connected to the first node of a differential gear set representable by a lever diagram having first, second, and third nodes. A motor/generator is connected to the second node. The third node is connected to an input member of a transmission gearing arrangement. A brake is selectively engagable to ground the first node to a stationary member. Engagement of the brake provides a regenerative braking mode and an electric-only driving mode, with the motor/generator connected to the transmission gearing arrangement through the differential gear set. Various clutches may be provided for lock-up or selective connection of the engine, including arrangements which reduce motor/generator torque required for engine starting while in electric-only driving. A method of operating a vehicle maintains the engine speed at an optimum level to the extent possible given battery charge levels and operator commands.

Abstract: An electromechanical transmission is provided with a structural support member that supports a motor/generator in a space efficient way; particularly, the motor/generator is supported from one side only to save space axially in the transmission. Specifically, a stationary structural support member circumscribes an outer surface of and supports a stator while extending radially-inward of a rotor and at least partially supporting the rotor. A rotor hub rotatable with respect to the structural support member is used to support an inner surface of the rotor. The structural support member substantially encloses the stator and rotor from one direction along the axis of rotation. However, the stator and rotor have no additional support members in the opposing axial direction such that they are unenclosed from an opposing axial direction.

Abstract: A hybrid powertrain includes a control unit that regulates electric power interchange an energy storage device and a motor/generator for causing selective torque generation by the motor/generator and for controlling engagement of torque-transmitting mechanisms. The control unit is configured to place the torque-transmitting mechanism in slipping engagement to launch the vehicle and thereby decouple a fixed relationship between engine torque and motor/generator torque or between engine torque and torque at the output member. A method of operating a hybrid vehicle powertrain is also provided.

Abstract: A vehicle propulsion system includes an internal combustion engine having an engine output, an electro-mechanical transmission and a control system. The engine output is coupled to the transmission output at a speed ratio which is established by one of a plurality of electrically variable or fixed operating modes. Selection and control among the various operating modes is managed by a control in accordance with preferred optimum operating costs.

Abstract: A hybrid electric vehicle (HEV) power system is provided that includes a vehicle electrical system (VES), an inverter-controller unit (ICU) and an AC electric motor/generator unit (MGU). The VES includes a first DC voltage source and a second DC voltage source coupled in series with the first DC voltage source. The VES also includes a first electrical load coupled across the first DC voltage source, and a second electrical load coupled across the second DC voltage source. The ICU is coupled across the first DC voltage source and the second DC voltage source and is designed to convert DC power from the first DC voltage source and the second DC voltage source to generate AC power for the AC electric MGU. Together the DC voltage sources can replace a conventional high-voltage DC voltage source. In some implementations, techniques are provided for “charge balancing” the first DC voltage source and the second DC voltage source without expensive devices.

Abstract: An input shaft for a hybrid transmission includes a cylindrical hollow shaft portion having internal and external surfaces. The internal surface defines an internal cavity coaxial with the hollow shaft portion and has a splined portion configured to allow power to be transferred to the hollow shaft portion. The input shaft may further include a freeze plug press-fit in the internal cavity, configured to fluidly seal the inner cavity in embodiments with a cavity extending throughout the input shaft. The splined portion may be a broached spline. A method of manufacturing a hybrid powertrain includes forming a hollow transmission input shaft and press-fitting a plug into it, such that the shaft is internally fluid sealed. The shaft is mated to the transmission which may then be filled with fluid and tested for operability. The shaft may be dry-mated to an engine output member for common rotation therewith.

Abstract: A vehicle powertrain for a hybrid vehicle includes an electronically variable transmission (EVT) with an input member to receive mechanical rotary power from the engine, an output member to provide mechanical rotary power to a vehicle powertrain to propel the vehicle, and an EVT gear train configured to selectively and operatively couple the input member to the output member. The EVT further includes first and second motor/generators driveably coupled to the gear train. A selectively engageable input brake mechanism is provided to create a reaction torque for the motor/generators thereby enabling the motor/generators to be used with additive power for electric propulsion or regenerative braking. The input brake improves electrical power to mechanical power conversion efficiency by reducing power circulation when the EVT is operated in electric drive, engine off mode.

Abstract: A torque-transmitting assembly is provided that includes a dog clutch isolated by a device such as a rotary hydrostatic damper from relative loading on the torque input member and torque output member that it is to connect for common rotation and torque transmission. Although its use is not limited to electrically-variable transmissions, the torque transmitting assembly is able to function even with the large inertia and potentially random torque inputs associated with theses types of transmissions.

Abstract: An electrically variable transmission has a differential gear set with first, second and third members operatively connected between an input member and an output member. The input member is also operatively connected to an engine for receiving power from the engine. The transmission also includes a compound motor/generator that has a single stator and at least two rotors, referred to herein as first and second rotors. The single stator is operable to provide power to, receive power from and transfer power between the two rotors. The rotors are each operatively connected to a different respective member of the differential gear set. The transmission has a mechanical power path and an electromechanical power path. In some embodiments, selectively engagable torque-transmitting mechanisms are positioned to allow various modes of electrically variable power flow. Input-split and compound-split embodiments are presented.

Abstract: An electric motor assembly in a vehicle powertrain is provided with a generally annular stator fit within an interior cavity of the powertrain defined by a housing. Roll pins are fit between the housing and the stator. The stator may have a plurality of first geometric features and the housing a plurality of second geometric features. The first geometric features are be configured to align with the second geometric features when the stator is fit within the cavity, with the roll pins fit between the housing and the stator at the aligned first and second geometric features. A method of assembling the electric motor assembly is also provided.

Abstract: An electrically variable transmission having a single motor/generator provides electrically variable power flow along dual power paths and provides an electrically variable reverse operating mode. The transmission includes a compound differential gear set having at least four gear elements operatively interconnected with one another. A transmission input member and the single motor/generator selectively provide power to a transmission output member via the differential gear set. The transmission includes a plurality of intermeshing gears, including a reversing gear and gears connected for rotation with the output member, for operatively connecting the differential gear set with the output member. Torque-transmitting mechanisms are selectively engagable to provide power flow between the input member and the output member in multiple operating modes, including a parallel hybrid electrically variable reverse operating mode utilizing the reversing gear.

Abstract: A transmission device for a powertrain system comprising a compound planetary gear set having four coaxial elements and a plurality of input nodes and an output node is described. The first input node is connected to an input shaft from an engine. The second input node is connected to a shaft of a first electrical machine. A plurality of input nodes are selectively connectable to a second electrical machine. The output node of the transmission device is connected to an output shaft of the transmission.