Progressively locking a friction clutch from a shift start time t1 thereby causes the friction clutch transmission torque Tfc to gradually increase from zero to a maximum value. With this, given that the transmission torque Tdc for a dog clutch is equal to the transmission input torque (motor torque Tm) minus Tfc, the transmission torque Tdc gradually decreases from the maximum value at tl. A withdrawal force Fdc = Fdc_L (a permitted upper limit value for the shift shock) is applied to the dog clutch beforehand from t2 which is a set time TMs that has passed after t1. With this, the dog clutch transmission torque Tdc which continues to decrease even after the instant t2, decreases to a torque value that corresponds to the dog clutch withdrawal force Fdc (= Fdc_L) at the instant t3 which is the time that the dog clutch 8c automatically switches from the engaged state to the disengaged state due to the withdrawal force Fdc (= Fdc_L), and with the progressive locking of the friction clutch, shifting is completed. Therefore, there is not time when the dog clutch and the friction clutch are both in a released state; therefore the automatic transmission is not in a neutral state during shifting, and it is possible to prevent a deterioration in shift quality.
SHIFT CONTROL DEVICE FOR AUTOMATIC TRANSMISSION
VERSCHIEBUNGSSTEUERUNGSVORRICHTUNG FÜR EIN AUTOMATIKGETRIEBE
DISPOSITIF DE COMMANDE DE CHANGEMENT POUR TRANSMISSION AUTOMATIQUE
2015-12-09
Patent
Electronic Resource
English
Gear shift control device for automatic transmission device
European Patent Office | 2021
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