Shift control system and method for V-belt type continuously variable transmission
AssigneeJATCO Ltd
InventorsMasahiro Yamamoto, Yoshihisa Kodama, Hiroyasu Tanaka, Takuichiro Inoue
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Abstract
A shift control system for a V-belt type continuously variable transmission is provided. The shift control system comprises a controller programmed to store an actual transmission ratio of the continuously variable transmission at stop of an associated vehicle drive source, and inhibit, at restart of the vehicle drive source, an initializing operation for returning an operational position of the shift actuator to a standard position when the actual transmission ratio is more on a high-speed side than a predetermined transmission ratio. A shift control method is also provided.
Claims9
A shift control system for a V-belt type continuously variable transmission having a primary pulley, a secondary pulley, a V-belt wound around the primary pulley and the secondary pulley, and a shift actuator for variably controlling V-shaped groove widths of the primary pulley and the secondary pulley through variable control of a difference between a primary pulley pressure and a secondary pulley pressure so that an actual transmission ratio attained by a rotational speed ratio between the primary pulley and the secondary pulley becomes equal to a target transmission ratio corresponding to an operational position of the shift actuator, the shift control system comprises a controller programmed to:
- store an actual transmission ratio of the continuously variable transmission at stop of an associated vehicle drive source;
- and
- inhibit, at restart of the vehicle drive source, an initializing operation for returning an operational position of the shift actuator to a standard position when the actual transmission ratio is more on a high-speed side than a predetermined transmission ratio.
A shift control system for a V-belt type continuously variable transmission having a primary pulley, a secondary pulley, a V-belt wound around the primary pulley and the secondary pulley, and a shift actuator for variably controlling V-shaped groove widths of the primary pulley and the secondary pulley through variable control of a difference between a primary pulley pressure and a secondary pulley pressure so that an actual transmission ratio attained by a rotational speed ratio between the primary pulley and the secondary pulley becomes equal to a target transmission ratio corresponding to an operational position of the shift actuator, the control system comprises:
- means for storing a transmission ratio of the continuously variable transmission at stop of an associated vehicle drive source;
- means for determining whether the transmission ratio at stop of the associated vehicle drive source is more on a high-speed side than a predetermined transmission ratio;
- and
- means for inhibiting, at restart of the vehicle drive source, an initializing operation for returning an operational position of the shift actuator to a standard position when the transmission ratio at stop of the associated vehicle drive source is more on a high-speed side than the predetermined transmission ratio.
A shift control method for a V-belt type continuously variable transmission having a primary pulley, a secondary pulley, a V-belt wound around the primary pulley and the secondary pulley, and a shift actuator for variably controlling V-shaped groove widths of the primary pulley and the secondary pulley through variable control of a difference between a primary pulley pressure and a secondary pulley pressure so that an actual transmission ratio attained by a rotational speed ratio between the primary pulley and the secondary pulley becomes equal to a target transmission ratio corresponding to an operational position of the shift actuator, the shift control method comprises:
- storing an actual transmission ratio of the continuously variable transmission at stop of an associated vehicle drive source;
- and
- inhibiting, at restart of the vehicle drive source, an initializing operation for returning an operational position of the shift actuator to a standard position when the actual transmission ratio is more on a high-speed side than a predetermined transmission ratio.
Dependencies are inferred from the claim text.