CONTROL APPARATUS FOR A HYBRID VEHICLE DRIVE SYSTEM

摘要

A control apparatus for a hybrid vehicle drive system 10, which permits sufficient utilization of the electric energy stored in the battery and includes a drive mode switching portion 60 configured to bring a clutch CL1 or a brake BK1 into its engaged state, for switching the drive system 10 from an EV drive mode in which a vehicle drive force is generated by at least one of first and second electric motors MG1 and MG2 while a crankshaft 12a of an engine 12 is connected to a housing 26, to a constant-speed-ratio drive mode in which the vehicle drive force is generated by at least one of the first and second electric motors MG1 and MG2 while a ratio of an output speed NOUT of the drive system 10 to a speed of a rotary motion received from the engine 12 is held constant, when an operating speed NMG1, NMG2 of the first or second electric motor MG1, MG2 has been raised to a predetermined threshold value in the EV drive mode. Accordingly, the desired output speed NOUT can be established at a relatively low value of the operating speed NMG1, NMG2 of the first or second electric motor MG1, MG2, so that the electric energy stored in the battery 48 can be sufficiently utilized.

主权项

1. A control apparatus for a drive system of a hybrid vehicle including: a differential device which comprises a first differential mechanism and a second differential mechanism and which comprises four rotary components; an engine, a first electric motor, a second electric motor and an output rotary member which are respectively connected to said four rotary components; and a coupling element which is placed in an engaged state to hold constant a ratio of an output speed of said first or second differential mechanism to a speed of a rotary motion received from said engine, the control apparatus comprising:
a drive mode switching portion configured to bring said coupling element into the engaged state, for switching said hybrid vehicle drive system from a first drive mode in which a drive force to drive the hybrid vehicle is generated by at least one of said first and second electric motors while an output shaft of said engine is connected to a stationary member of the hybrid vehicle, to a second drive mode in which the drive force to drive the hybrid vehicle is generated by at least one of the first and second electric motors while the ratio of the output speed of the first or second differential mechanism to the speed of the rotary motion received from the engine is held constant, when an operating speed of said first or second electric motor has been raised to a predetermined threshold value in said first drive mode.