Lock-up clutch control device for vehicle

Abstract

To provide a lockup clutch control device of a vehicle which can make compatible both the suppression of the lowering of fuel economy and the suppression of the lowering of the durability of a lockup clutch while suppressing the generation of a surge.SOLUTION: An electronic control device 100 prohibits the complete engagement of a lockup clutch 20 (a) when it is estimated that a surge level Lsrg exceeds a determination level Lsrg_jdg on the basis of an air-fuel ratio A / F, an ignition retardation amount θdly, an engine rotational speed Ne, and engine torque Te, and (b) even if the complete engagement of the lockup clutch 20 is prohibited, when there is established at least one of conditions that the air-fuel ratio A / F is equal to or lower than a determination ratio A / F_jdg, the ignition retardation amount θdly is equal to or larger than a determination retardation amount θdly_jdg, a catalyst temperature THcat is equal to or higher than a determination temperature THcat_jdg, and a fuel increase amount coefficient α for the protection of a catalyst is equal to or higher than a determination coefficient α_jdg, the electronic control device permits the complete engagement of the lockup clutch 20.SELECTED DRAWING: Figure 1

Images