Control method and device for automatic transmission
AssigneeDenso Corporation
InventorsFuminori Suzuki, Akira Takagi
Life of this patent
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Abstract
A control method for an automatic transmission is capable of quickly determining whether gear shifting is permissive. The control method varies the command value input to an engaging-side electromagnetic valve that adjusts a hydraulic pressure applied to a frictional element to be engaged in a target gear in a specific time period, then determines a time variation in another time period of the hydraulic pressure applied to the frictional element that is adjusted by the engaging-side electromagnetic valve according to the input command value and detected by a detecting means. Determination of whether gear shifting is permissive or not on the basis of the time variation is thus determined.
Claims16
A control method for an automatic transmission comprising:
- applying a hydraulic pressure of a working fluid to a plurality of frictional elements of the automatic transmission to control shifting of gears of the automatic transmission;
- varying a command value given to means for adjusting pressure of the working fluid;
- and
- determining whether gear shifting is permissive or not based on time variation of the hydraulic pressure applied to the frictional element that is adjusted by the pressure adjusting means according to the command value and detected by a means for detection of hydraulic pressure.
A control device for an automatic transmission for applying a hydraulic pressure of a working fluid to a plurality of frictional elements of the automatic transmission to control shifting of gears of the automatic transmission, the device comprising:
- means for adjusting a hydraulic pressure applied to at least one of the frictional elements according to a command value;
- means for detecting the applied hydraulic pressure;
- and
- means for varying the command value given to the pressure adjusting means and for determining whether gear shifting is permissive or not based-on time variation of the applied hydraulic pressure detected by the detecting means.
Dependencies are inferred from the claim text.