A launch control method for a continuously variable transmission (CVT) is provided, where the CVT comprises a hydro-mechanical variator (12), a summing transmission (34) connected to an output side of the variator (12), and a clutch (52) for selectively connecting the summing transmission (34) to an output member (4). The method determines whether a launch has been requested (300), and adjusts a variable displacement pump (14) of the variator to a predetermined fixed displacement (302). Engagement of the clutch is commenced, and the method then determines whether a predetermined degree of slip exists between input and output elements of the clutch (304). The clutch is held at its present state of engagement when the predetermined degree of slip has been established, and the variator is placed into a torque control mode (306). The method then determines when there is zero slip between the input and output elements of the clutch (308), and then instructs full engagement of the clutch (310). The method then holds the pump of the variator at its current displacement until a predetermined time period has elapsed (312), before reverting to a standard transmission control algorithm (314). A CVT is also provided.
A variator-assisted transmission and launch control methods for such a transmission
Variatorunterstützte Übertragung und Start-Steuerverfahren für eine solche Übertragung
Transmission assistée par variateur et procédés de commande de lancement d'une telle transmission
2020-11-04
Patent
Electronic Resource
English
IPC: | B60W CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION , Gemeinsame Steuerung oder Regelung von Fahrzeug-Unteraggregaten verschiedenen Typs oder verschiedener Funktion |
Variator-assisted transmission and launch control methods for such a transmission
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