Abstract: A system for controlling shifting includes an engine, a driven member, and a shiftable transmission including an input shaft coupled to the engine and an output shaft coupled to the driven member. The system further includes a plurality of sensors for monitoring parameters of at least one of the engine, the driven member, or the transmission, a torque converter disposed between the engine and the input shaft, and an electronic control unit including a processor and a memory. The electronic control unit is operable to receive sensed parameters from the plurality of sensors, determine a torque ratio across the torque converter based on the sensed parameters, determine a speed ratio associated with the torque ratio, determine a rotational speed of the input shaft based on the speed ratio and the sensed parameters, and make a shifting decision based on the rotational speed of the input shaft.
Abstract: There is disclosed a continuously variable ratio transmission assembly (“variator”) comprising a roller which transmits drive between a pair of races, the roller being movable in accordance with changes in variator ratio, a hydraulic actuator which applies a biasing force to the roller, at least one valve connected to the actuator through a hydraulic line to control pressure applied to the actuator and so to control the biasing force, and an electronic control which determines the required biasing force and sets the valve accordingly, wherein the valve setting is additionally dependent upon a rate of flow in the hydraulic line.
Abstract: A control system for a vehicle having first and second wheels is provided that includes a differential apparatus adapted to distribute torque between the first and second wheels and a traction controller for controlling operation of the differential apparatus from vehicle launch up to a predetermined vehicle speed. The traction controller is configured to engage the differential apparatus in a first operating state according to at least one vehicle operating parameter indicative of a low traction operating condition and to further control engagement of the differential apparatus in a second vehicle operating state during the low traction operating condition according to a difference between an actual vehicle yaw rate and a predetermined target vehicle yaw rate. The control system also includes a stability controller for controlling engagement of the differential apparatus at or above the predetermined vehicle speed.
February 2, 2007
Date of Patent:
September 21, 2010
Damrongrit Piyabongkarn, Jae Y. Lew, John A. Grogg, Robert J. Kyle
Abstract: In an automatic transmission including a gear unit with a second brake connected in series with a one-way clutch and a first brake that is not connected with a one-way clutch, the second brake and the first brake are controlled by linear solenoid valves individually. A vehicle load is detected, and when the vehicle is in a high load state, at first the second brake performs an engagement control, then after input rotation to the gear unit is synchronized with output rotation of the gear unit, the first brake performs an engagement control. When the vehicle is in a low load state, at first the first brake performs an engagement control, then after input rotation to the gear unit is synchronized with output rotation of the gear unit, the second brake performs an engagement control.
Abstract: This clutch device has a first cam mechanism and a second cam mechanism disposed on a relatively rotatable a pair of members. When the first cam mechanism is pushed by a piston to one of the pair of members rotating in a direction, the first cam mechanism generates a thrust force corresponding to an input torque and thereby the relatively rotating members are engaged. When the second cam mechanism is pushed by a piston to one of the pair of members rotating in a reverse direction, the second cam mechanism generates a thrust force corresponding to the pushing force of the piston, and thereby the relatively rotating members are engaged. A return spring giving a biasing force to separate the second cam member from the one of relatively rotating member is designed not to reduce the thrust force generated by the first cam member during the action of the first cam mechanism.
Abstract: A friction brake band actuating system for automatic transmissions operative for obtaining smooth self-synchronized freewheeler type shifts without the use of one-way roller or sprag clutches. The band functions normally like a conventional brake band providing engine braking while the vehicle is coasting. For both upshifting and downshifting, the actuating system is staged in a one-way mode at the beginning of the shift event. In the one-way mode the self-synchronizing brake band utilizes the band reaction force to regulate a common pressure, which is acting on the apply piston and also on a reaction piston provided for counteracting the force at the band anchor end. The resulting torque capacity of the band varies in direct relationship with the torque the band is transmitting.
Abstract: This bi-directional clutch combines the functions of two separate opposite acting clutching systems, each consisting of a one-way roller or sprag clutch and an in-series coupled multi-plate friction unit. The clutch is operative regardless of direction of torque to provide fully synchronized upshifts and downshifts of gear ratios in automatic transmissions. This clutch incorporates a torque responsive reaction plate which regulates the apply pressure in accordance to the torque carried by the clutch. Consequently, when the torque acting in selected direction descends to zero at the start of torque reversal, the clutch is automatically released. Direction of one-way action is selected by switching clutch feed and exhaust oils by controls.