Lockup control device and lockup control method for vehicle power transmission device
AssigneeToyota Jidosha Kabushiki Kaisha
InventorKen Imamura
Life of this patent
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Abstract
Provided is a lockup control device and a lockup control method for a vehicle power transmission device provided with a fluid transmission device including a lockup clutch. The lockup clutch is controlled to perform slip-engagement such that a differential rotation between an input-side rotating member and an output-side rotating member of the fluid transmission device is a target differential rotation set in advance, and the target differential rotation is corrected based on transition of a heat accumulation amount applied to friction members of the lockup clutch.
Claims8
A lockup control device for a vehicle power transmission device, the vehicle power transmission device including a fluid transmission device including a lockup clutch, the lockup control device comprising:
- a processor programmed to:
- execute flex lockup control to cause slip-engagement of the lockup clutch such that a differential rotation between an input-side rotating member and an output-side rotating member of the fluid transmission device is a target differential rotation set in advance;
- calculate a heat accumulation amount applied to friction members of the lockup clutch;
- calculate a long-term change that is a change in a cumulative heat accumulation amount obtained by cumulating the heat accumulation amount, as a transition of the heat accumulation amount;
- and
- correct the target differential rotation to make the target differential rotation smaller when the long-term change is large, as compared to when the long-term change is small.
A lockup control method for a vehicle power transmission device, the vehicle power transmission device provided with a fluid transmission device including a lockup clutch, the lockup control method comprising:
- controlling the lockup clutch to perform slip-engagement such that a differential rotation between an input-side rotating member and an output-side rotating member of the fluid transmission device is a target differential rotation set in advance;
- calculating a heat accumulation amount applied to friction members of the lockup clutch;
- calculating a long-term change that is a change in a cumulative heat accumulation amount obtained by cumulating the heat accumulation amount, as a transition of the heat accumulation amount;
- and
- correcting the target differential rotation to make the target differential rotation smaller when the long-term change is large, as compared to when the long-term change is small.
Dependencies are inferred from the claim text.