An electromechanical power-split system and a method of operating thereof is provided, with a mechanical drive branch including an internal combustion engine (3), and with an electric drive branch including a first motor-generator block (59) including a first motor-generator (1) and a second motor-generator block (60) including a second motor-generator (2), the first motor-generator (1) is connectable to the internal combustion engine (3) and to the second motor-generator (2). The system includes a planetary gearset (4) with dual planet gears (46) and four input/output members for altering the flow ratio of the mechanical and electric drive branch . Each dual planet gear (46) is connected to the four input/output members, which are a first pair of input/output members formed by a first sun gear (41) and a ring gear (44), and a second pair of input/output members formed by a second sun gear (143) and a planet carrier (45).

A vehicle includes a residual pressure holding valve provided downstream a feed pump of a fuel to hold a pressure in a fuel pipe leading to the port injection valve. Residual pressure holding valve is opened to return the fuel in the fuel pipe to the fuel tank when the pressure in the fuel pipe exceeds a valve opening pressure, and closed when the pressure in the fuel pipe is lower than the valve opening pressure. At the time of a request to reduce a target pressure of the fuel to be supplied to the electric feed pump, a control device refrains from causing the target pressure to decrease when a load of the engine is smaller than a prescribed value, and causes the target pressure to decrease when the load of the engine is greater than the prescribed value.

A power transmission apparatus has a power distribution mechanism which is connected to an engine and a first motor-generator an in which at least three rotation elements enable to rotate in differential motions to one another, a power combining mechanism which is connected to the power distribution mechanism, a second motor-generator and an output shaft and in which four rotation elements enable to rotate in differential motions to one another, a brake mechanism which enables to selectively fix a rotation element of the power combining mechanism and a brake mechanism which enables to selectively fix a rotation element of the power combining mechanism which is connected to the engine.

A drive transmission device includes a clutch mechanism. The clutch mechanism includes a drive transmission member that is coupled to a first rotation member via a torque limiter and is arranged in a fitting part of a second rotation member and a third rotation member, and a transmission member moving part that includes a first gap and a second gap, the first gap being formed in the fitting part and having a width wider than the thickness of the drive transmission member and the second gap being formed in the fitting part and having a width that is equal to or smaller than the thickness of the drive transmission member, the transmission member moving part being formed in such a way that the width thereof becomes smaller about a rotation axis in the fitting part.

A control device for a hybrid vehicle carries out, when a vehicle travels in a downhill control section or a congestion control section, pre-charge/discharge control of changing a target state of charge (SOC) SOCcntr from a standard SOC SOCcntr-n to a specific SOC, and is within a permissible range, in a period in which the vehicle travels from a control start point (Ds) to at least a start point (Dk) of a subject downhill section or a subject congested section. Further, the control device is configured to inhibit, when return control is carried out while the pre-charge/discharge control is being carried out, the pre-charge/discharge control from a start time point (D5) of the return control to a time point (D9) at which the vehicle has passed through the control section. As a result, fuel efficiency can be improved when the return control is carried out during the pre-charge/discharge control.

To arrange a power unit, an electric power conversion unit, and engine-related components compactly, a drive motor, a reduction drive, a generator, and an engine body are integrally arranged in this order in a vehicle width direction of a power unit compartment such that respective heights thereof are substantially the same. An electric power conversion unit, in which a motor inverter, an electric power generation inverter, and a DC/DC converter are integrated, is arranged above the drive motor, the reduction drive, and the generator. Engine-related components such as a low-voltage battery, an air cleaner, and an oil filter are arranged above the engine body.

A control apparatus for a vehicle that includes an engine as a drive power source, a rotating machine as an electric power generator, and an electric storage device. The control apparatus executes an automatic drive control for automatically controlling a torque of the drive power source in accordance with a requested drive torque without requiring an acceleration/deceleration operation by a driver of the vehicle. During an engine running of the vehicle, the rotating machine is rotated by the engine to generate an electric power, and a charging amount, by which the electric storage device is to be charged, is controlled by controlling the electric power generated by the rotating machine. The control apparatus is configured, during an automatic driving of the vehicle, to set the charging amount such that the charging amount is smaller when the requested drive torque is small than when the requested drive torque is large.

A vehicle drive apparatus includes: an engine; a rotary machine; an output member coupled to a drive wheel of a vehicle; a differential mechanism configured to couple the engine, the rotary machine, and the output member together to be differentially rotatable via a plurality of differentially rotatable rotational elements; and an elastic member configured to couple a rotation shaft of the rotary machine to the rotational element of the differential mechanism to be relatively rotatable.

A vehicle drive apparatus includes: an engine; a rotary machine; an output member coupled to a drive wheel of a vehicle; a differential mechanism configured to couple the engine, the rotary machine, and the output member together to be differentially rotatable via a plurality of differentially rotatable rotational elements; and an elastic member configured to couple a rotation shaft of the rotary machine to the rotational element of the differential mechanism to be relatively rotatable.

A drive system includes: a first planetary gear unit, in which a carrier is connected to an internal combustion engine, a sun gear is connected to a first MG, and a ring gear is connected, via a first drive gear and a first driven gear, to a counter shaft; and a second planetary gear unit, in which a brake is provided to a sun gear, a carrier is connected to the internal combustion engine, and a ring gear is connected, via a second drive gear and a second driven gear, to the counter shaft. A gear ratio of the first drive gear and the first driven gear is larger than a gear ratio of the second drive gear and the second driven gear.