Speed change control system for vehicle
AssigneeToyota Jidosha Kabushiki Kaisha
InventorsSoichiro Shimura, Tatsuya Imamura
Life of this patent
Estimating the term…
Abstract
A speed change control system for a vehicle configured to reduce uncomfortable feeling of a driver when shifting an operating mode via the fixed mode. When a required drive force to propel the vehicle is increased, a controller shifts the operating mode from a first continuously variable mode to a second continuously variable mode via a fixed mode. In this case, the controller increases an engine speed to a first target speed from a point when shifting from the fixed mode to the second continuously variable mode, and further increase the engine speed to a second target speed calculated based on the required drive force. In addition, the controller reduces the first target speed with an increase in at least any one of a first elapsed time and a second elapsed time.
Claims7
A speed change control system for a vehicle, comprising:
- an engine;
- and
- a speed change mechanism that is connected to the engine,
- wherein the speed change mechanism is adapted to shift an operating mode among
- a first continuously variable mode in which a speed of the engine may be varied continuously,
- a second continuously variable mode in which the speed of the engine may also be varied continuously, and
- a fixed mode in which a speed ratio between the engine and a pair of drive wheels is fixed to a predetermined value,
- the control system comprising a controller that controls the speed change mechanism,
- wherein the controller is configured to
- shift the operating mode between the first continuously variable mode and the second continuously variable mode via the fixed mode when a required drive force to propel the vehicle is increased,
- increase the speed of the engine to a first target speed from a point at which the operating mode is shifted from the fixed mode to the second continuously variable mode,
- further increase the speed of the engine to a second target speed calculated based on the required drive force, and
- set the first target speed to a smaller value with an increase in at least any one of
- a first elapsed time from a point at which the required drive force is increased to a point at which the operating mode is shifted from the fixed mode to the second continuously variable mode, and
- a second elapsed time from a point at which a change rate of longitudinal acceleration of the vehicle is reduced less than a predetermined value to the point at which the operating mode is shifted from the fixed mode to the second continuously variable mode.
Dependencies are inferred from the claim text.