Abstract: An assembly and method is provided for reducing clutch wear due to centrifugal apply pressure within a clutch-apply cavity. The assembly comprises a rotatable clutch housing, a clutch-apply piston disposed within a clutch-apply cavity, and a balance piston. The balance and apply pistons define a balance cavity including a liquid fill channel and a dedicated air exhaust channel having a control radius configured to at least partially offset or compensate for the centrifugal apply force generated within the clutch-apply cavity when the clutch assembly rotates. The method includes configuring the balance cavity with an exhaust channel for exhausting fluid, and providing the exhaust channel with a control radius determined by the innermost radius of rotating fluid within the balance cavity as measured with respect to the centerline of rotation of the clutch assembly, the control radius being suitable for exhausting any excess of centrifugal balance force over centrifugal apply force.

Abstract: The present invention details a sleeve and bushing of an electromechanical automatic planetary transmission. The sleeve and bushing operate to confine the desired flow of transmission lubricant through the components of the planetary gear arrangement. Additionally, the sleeve and bushing assist in maintaining a sufficient pressure level in the cavity of the planetary carrier to enable the lubricant to reach the bearings of the pinion gear. Moreover, the radius or size of the bushing/sleeve arrangement can be adjusted to occupy the radial clearance or cavity between the sun gear and main shaft for an automatic transmission with axially separable splined sun gear and sun gear shaft.

Abstract: This invention relates to grounding the mechanical loads of an electrically variable transmission with a park pawl system located in the end cover portion of the transmission housing. The end cover portion is configured to cover the park pawl system and engagement gear. A support hub is interfittable with the end cover portion of the transmission and sufficiently secured thereto so as to ground the park pawl loads. The hub also functions to guide oil to the cavity of a piston-clutch assembly. A method of securing a hub to an electrically variable transmission housing is also provided.

Abstract: This invention relates to a method and structure for minimizing noise output of the electric motors of an electrically variable transmission by placing springs between the ball bearings of the motors and a housing part of the motor assembly. The springs are preferably disc or wave springs configured to consistently force the balls against the race of the ball bearings, thereby minimizing the noise output of the electrically variable transmission when in operation.

Abstract: This invention relates to an actuable park pawl system for a hybrid electro-mechanical transmission located in the end cover portion of the transmission housing. The end cover portion is configured to cover the park pawl system and ancillary components such as the actuator guide. This enables the actuator guide to be an open-ended structure. A method of securing a park engagement system with an open-ended actuator guide in a vehicle transmission is further provided.

Abstract: A hybrid transmission including two electric motors and a plurality of planetary gear sets operatively connectable to the motors and to an engine is provided. Novel motor features are provided including structure adapted to improve reliability and to facilitate assembly. More precisely, a method is provided for locating and installing the components of a motor, including a rotor and a stator, within a covered housing to form a motor module. A plurality of rotor bearings and a position/speed sensor are also preferably added to the motor module. After the motor module is assembled, the motor may be tested and thereafter the motor module can be installed into a hybrid transmission as a single component utilizing conventional transmission assembly methods.

Abstract: A motor resolver assembly includes a resolver stator and a resolver rotor positioned radially inward of and rotatable with respect to the resolver stator. First and second relatively rotatable shield components generally surround the resolver stator and rotor to shield them from electromagnetic energy from a radially outward motor rotor and motor stator. A method of measuring speed and position of the motor rotor relative to the motor stator is also employed.

Abstract: A method and apparatus for efficiently cooling and lubricating rotating components in a hybrid transmission is provided. By efficiently managing cooling flow to and between the rotating elements, flow requirements and associated pumping requirements within the drive unit are minimized. In addition, by providing a method for placing the fluid directly on the required components, spin losses associated with component contact with stray oil are reduced. Combined, the reduction in pumping and spin losses create a more efficient drive unit and an overall more efficient hybrid drive system which directly leads to higher fuel economy.

Abstract: The present invention relates to a torsional damper for an electrically-variable transmission. The torsional damper is equipped with a lock-out clutch to directly couple the engine to the input shaft of the transmission. The electric motors provided with the electrically-variable transmission can serve to effectively cancel out engine compression pulses when the springs of the torsional damper are locked out. The present invention also includes damper springs of variable rates to effectively attenuate distinctive or inconsistent torque fluctuations when the engine is operating in displacement-on-demand mode.

Abstract: This invention relates to the housing of a hybrid electro-mechanical transmission consisting of park pawl system located in the end cover portion of the transmission housing. The end cover portion is configured to cover the park pawl system and allow access to the components of the park pawl system for assembly or service even as the end cover portion remains attached to the main housing of the transmission. An access cover and seal for the access opening in the end cover portion is also provided. The access opening is designed to be small enough so that the end cover portion can also provides structural support to a main housing portion during operation of the transmission. A method of selectively providing access to a park pawl system located in the end cover portion of a transmission housing is also provided.

Abstract: An improved hybrid electro-mechanical vehicular transmission includes motor/generator modules assembled from like components. This is accomplished by providing “punch-out” tabs on the motor/generator module housing enabling the housing to be used on either the first or second motor/generator module within a hybrid electro-mechanical vehicular transmission, thus enabling like components to be used within both the first and second motor/generator module.

Abstract: A torque-transmitting mechanism has a plurality of friction plates, which are forced into engagement by a fluid-operated piston and reacted in engagement by a backing plate. The backing plate is assembled on a rotatable shaft to be aligned with splines on the shaft to prevent axial removal of the backing plate without rotation thereof which is restricted due to a spline engagement between the backing plate and the shaft.

Abstract: The present invention is drawn to a method and apparatus for cooling a hybrid transmission electric motor. More precisely, an annular chamber is formed between a housing for the electric motor and a transmission housing. Coolant is disposed in the annular chamber and is applied to the electric motor through a plurality of coolant apertures in the motor housing to cool the motor.

Abstract: A selectively engageable friction device, such as a clutch or brake, requires a supply of cooling fluid during engagement. The friction device is engaged by fluid directed to a piston through a passage in a shaft. A stepped diameter tube is slidably disposed in the shaft and is movable therein by fluid pressure to control the flow of lubrication and cooling fluid which is directed to the friction device during engagement and to prevent distribution of lubrication and cooling fluid when the device is disengaged.

Abstract: A parking pawl is pivotally mounted on a transmission housing for selective engagement with a park gear which is rotatable with a transmission output shaft disposed along a longitudinal axis in the transmission housing. The pawl is moved into engagement with the park gear by an axial face cam which is disposed for rotation on an axis supported transversely of the transmission housing.

Abstract: A hydraulic control for an automatically shifted power transmission has an electronically controlled governor pressure source which provides a speed and throttle sensitive pressure for controlling the shift points and trim boost in the transmission control. An inhibitor circuit is activated in the event of a discontinuance of the electrical control, resulting in maximum governor pressure, to permit selected vehicle operation in one forward ratio and a reverse ratio. Each ratio interchange is controlled by a respective shift valve and clutch control valve. Each clutch control valve has an integral trim control which is effective to control the pressure rise in the on-coming clutch without bypassing fluid to an exhaust. Also during a ratio interchange, an off-going clutch is controlled at a reduced pressure during a portion of the ratio interchange.

Abstract: A shift fork for a forward-reverse shift mechanism has a hydraulic piston portion for moving the shift fork. The piston is controlled by a hydraulic valve system. The valve system is effective to delay the engagement of the respective forward and reverse, hydraulically-operated, torque transfer devices. The shift fork will enforce the establishment of the proper power path through a synchronizer prior to the engagement of the torque transfer control devices.

Abstract: A power transmission has a housing comprised of an end support, a casing, an end cover, a converter housing, an input shaft, an output shaft and a pair of identically dimensional countershafts. A bushing and oil feed sleeve are positioned on each end of each countershaft for cooperating with the end support connecting the housing for alignment therebetween and with the casing for alignment therebetween. Each countershaft has a pair of ratio gears rotatably disposed thereon and meshing with respective output gears rotatable with the output shaft and a friction clutch is provided for each ratio gear. Four of the friction clutches which are disposed on the countershafts are identical in construction. A fifth clutch assembly, in line with the input shaft, can be shortened, if desired, by the elimination of one friction plate and one reaction plate.

Abstract: A power transmission has a housing comprised of an end support, a casing, an end cover, a converter housing, an input shaft, an output shaft and a pair of identically dimensional countershafts. A bushing and oil feed sleeve are positioned on each end of each countershaft for cooperating with the end support connecting the housing for alignment therebetween and with the casing for alignment therebetween. Each countershaft has a pair of ratio gears rotatably disposed thereon and meshing with respective output gears rotatable with the output shaft and a friction clutch is provided for each ratio gear. Four of the friction clutches which are disposed on the countershafts are identical in construction. A fifth clutch assembly, in line with the input shaft, can be shortened, if desired, by the elimination of one friction plate and one reaction plate.