Abstract: A liquid pressure circuit is provided in which connecting an accumulator (22) to a high pressure liquid path (Lh) by opening a cut-off valve (24a) and connecting a intake liquid path (Li) to the high pressure liquid path (Lh) by means of a switch valve (24b) enables a pump/motor (M) to be operated as a motor by liquid stored under pressure in the accumulator (22), connecting the accumulator (22) to the high pressure liquid path (Lh) by opening the cut-off valve (24a) and connecting the intake liquid path (Li) to a low pressure liquid path (Ll) by means of the switch valve (24b) enables the pump/motor (M) to be operated as a pump to thus store liquid of a tank (21) under pressure in the accumulator (22), and closing the cut-off valve (24a) and connecting the intake liquid path (Li) to the high pressure liquid path (Lh) by means of the switch valve (24b) enables the pump/motor (M) to rotate without load; it is therefore possible to switch between three circuits, that is, drive (motor operation), regeneration (p

Abstract: A liquid pressure circuit is provided in which connecting an accumulator (22) to a high pressure liquid path (Lh) by opening a cut-off valve (24a) and connecting a intake liquid path (Li) to the high pressure liquid path (Lh) by means of a switch valve (24b) enables a pump/motor (M) to be operated as a motor by liquid stored under pressure in the accumulator (22), connecting the accumulator (22) to the high pressure liquid path (Lh) by opening the cut-off valve (24a) and connecting the intake liquid path (Li) to a low pressure liquid path (Ll) by means of the switch valve (24b) enables the pump/motor (M) to be operated as a pump to thus store liquid of a tank (21) under pressure in the accumulator (22), and closing the cut-off valve (24a) and connecting the intake liquid path (Li) to the high pressure liquid path (Lh) by means of the switch valve (24b) enables the pump/motor (M) to rotate without load; it is therefore possible to switch between three circuits, that is, drive (motor operation), regeneration (p

Abstract: A hybrid vehicle is equipped with an internal combustion engine, a motor/generator, and a Rankine cycle system for recovering thermal energy of exhaust gas. The output of the Rankine cycle system is input into a transmission or, alternatively, converted into electric power and used for charging a battery. The Rankine cycle system has temperature setter that sets the temperature of steam at the outlet of an evaporator. A pressure setter is provided for setting steam pressure at the inlet of an expander. A pressure controller is provided for controlling the steam pressure at the inlet of the expander. The evaporator generates steam to be supplied at a pressure that is optimum for the expansion ratio of the expander. The Rankine cycle system is operated when the vehicle is accelerating or cruising and efficiently recovers thermal energy of the exhaust gas and reduces the fuel consumption of the internal combustion engine.

Abstract: An evaporator control system includes water supply amount control means for controlling at a target temperature the temperature of steam generated by heating water supplied to an evaporator with thermal energy of exhaust gas of an engine, by manipulating the amount of water supplied. The water supply amount controller determines the amount of water supplied to the evaporator based on the sum of a feedforward water supply amount calculated from an amount of change in a parameter representing a load state of the engine, a first feedback water supply amount calculated from the actual temperature of the steam generated by the evaporator, and further a second feedback water supply amount calculated from a parameter representing an internal state of the evaporator such as an internal density of the evaporator.

Abstract: A Rankine cycle system includes: an evaporator for heating a liquid-phase working medium with thermal energy of exhaust gas of an engine so as to generate a gas-phase working medium; a displacement type expander for converting the thermal energy of the gas-phase working medium generated by the evaporator into mechanical energy; a target pressure setter for setting a target pressure for the gas-phase working medium based on actual flow rate and temperature of the gas-phase working medium supplied to the expander; an estimated flow rate calculator for calculating an estimated flow rate of the gas-phase working medium supplied to the expander based on an output and a rotational speed of the engine; and a target rotational speed calculator for calculating a target rotational speed for the expander based on the estimated flow rate calculated by the estimated flow rate calculator and the target pressure set by the target pressure setter.

Abstract: A Rankine cycle system for recovering a heat energy of an exhaust gas is mounted on a hybrid vehicle including an internal combustion engine as a drive source for the vehicle and an electric generator motor. An output from the Rankine cycle system is input to a transmission and used to assist in a driving force from the internal combustion engine, or converted into an electric power and used to charge a battery. During acceleration and cruising of the vehicle, the heat energy of the exhaust gas is recovered by the Rankine cycle system, and during deceleration of the vehicle, a kinetic energy of a vehicle body is recovered as a regenerative electric power for the electric generator motor, thereby reducing the amount of fuel consumed in the internal combustion engine. Thus, in any operational state, vehicle energy efficiency is enhanced, thus reducing the fuel consumed.

Abstract: A Rankine cycle system is provided in which, in order to make a pressure (P) of a gas-phase working medium at the inlet of an expander (13) coincide with a target pressure (PO), a feedforward value (NFF) is calculated on the basis of the target pressure (PO) and a flow rate (Q) of the gas-phase working medium at the outlet of an evaporator (12), a feedback value (NFB) is calculated by multiplying a deviation (?P) of the pressure (P) of the gas-phase working medium at the inlet of the expander (13) from the target pressure (PO) by a feedback gain (kp) calculated on the basis of the flow rate (Q) of the gas-phase working medium, and the rotational speed of the expander (13) is controlled on the basis of the result of addition/subtraction of the feedforward value (NFF) and the feedback value (NFB).

Abstract: A Rankine cycle system is provided in which the amount of water supplied to an evaporator (12) and the rotational speed of an expander (13) are controlled so as to make the temperature of steam at the outlet of the evaporator (12) coincide with a target steam temperature. When the amount of water supplied to the evaporator (12) is decreased stepwise, the temperature of the steam at the outlet of the evaporator (12) increases slowly and converges to a predetermined temperature. When the rotational speed of the expander (13) is decreased stepwise the steam temperature increases quickly, although the increase is temporary.

Abstract: Evaporator temperature control means (U) that, in order to make the temperature of steam generated by heating water using exhaust gas of an engine coincide with a target temperature, controls the amount of water supplied to the evaporator based on the flow rate of the exhaust gas, the temperature of the exhaust gas, the temperature of the water, and the temperature of the steam. Calculating an exhaust gas flow rate (Gmix) based on a fuel injection quantity, an air/fuel ratio, and a rotational speed of the engine improves the precision and the responsiveness of the calculation. Controlling the amount of water supplied to the evaporator based on this exhaust gas flow rate (Gmix) therefore improves the accuracy with which the steam temperature is controlled so as to make it coincide with the target temperature.

Abstract: The catalyst warming control apparatus of the present invention is provided for a hybrid vehicle having an internal combustion engine, a generator for generating electric power from the output from the internal combustion engine, a power storage unit for storing electric power generated by the generator, and an electric motor driven by the electric power stored in the power storage unit, the hybrid vehicle being driven by at least one of the outputs from the internal combustion engine and the motor.

Abstract: Evaporator temperature control means (U) that, in order to make the temperature of steam generated by heating water using exhaust gas of an engine coincide with a target temperature, controls the amount of water supplied to the evaporator based on the flow rate of the exhaust gas, the temperature of the exhaust gas, the temperature of the water, and the temperature of the steam. Calculating an exhaust gas flow rate (Gmix) based on a fuel injection quantity, an air/fuel ratio, and a rotational speed of the engine improves the precision and the responsiveness of the calculation. Controlling the amount of water supplied to the evaporator based on this exhaust gas flow rate (Gmix) therefore improves the accuracy with which the steam temperature is controlled so as to make it coincide with the target temperature.

Abstract: In a vehicle designed so that a driven wheel is driven by uniting an output from an engine and an output from a Rankine cycle system to each other, an accelerator pedal and a throttle valve are connected electrically to each other by a DBW control unit. When an accelerator opening degree (?ap) commanded by a driver is increased, a throttle opening degree (?th) is increased by a correcting amount (??th) more than a value proportional to the accelerator opening degree (?ap), thereby compensating for an output shortage due to a response delay of the output from the Rankine cycle system. When the accelerator opening degree (?ap) commanded by the driver is decreased, the throttle opening degree (?th) is decreased by the correcting amount (??th) more than the value proportional to the accelerator opening degree (?ap), thereby compensating for an output excessiveness due to the response delay of the output from the Rankine cycle system.

Abstract: A hybrid vehicle is equipped with an internal combustion engine, a motor/generator, and a Rankine cycle system for recovering thermal energy of exhaust gas. The output of the Rankine cycle system is input into a transmission or, alternatively, converted into electric power and used for charging a battery. The Rankine cycle system has temperature setter that sets the temperature of steam at the outlet of an evaporator. A pressure setter is provided for setting steam pressure at the inlet of an expander. A pressure controller is provided for controlling the steam pressure at the inlet of the expander. The evaporator generates steam to be supplied at a pressure that is optimum for the expansion ratio of the expander. The Rankine cycle system is operated when the vehicle is accelerating or cruising and efficiently recovers thermal energy of the exhaust gas and reduces the fuel consumption of the internal combustion engine.

Abstract: A Rankine cycle system (9) for recovering a heat energy of an exhaust gas is mounted on a hybrid vehicle including an internal combustion engine (1) as a drive source for traveling of the vehicle and an electric generator motor (2). An output from the Rankine cycle system (9) is input to a transmission (4) and used to assist in a driving force from the internal combustion engine (1), or converted into an electric power and used to charge a battery (8). During acceleration and cruising of the vehicle, the heat energy of the exhaust gas is recovered by the Rankine cycle system (9), and during deceleration of the vehicle, a kinetic energy of a vehicle body is recovered as a regenerative electric power for the electric generator motor (2), thereby reducing the amount of fuel consumed in the internal combustion engine (1). Thus, even when the vehicle is in any operational state, the energy recovery efficiency can be enhanced to the maximum to reduce the amount of fuel consumed in the internal combustion engine.

Abstract: In a vehicle designed so that a driven wheel is driven by uniting an output from an engine and an output from a Rankine cycle system to each other, an accelerator pedal and a throttle valve are connected electrically to each other by a DBW control unit. When an accelerator opening degree (&thgr;ap) commanded by a driver is increased, a throttle opening degree (&thgr;th) is increased by a correcting amount (&Dgr;&thgr;th) more than a value proportional to the accelerator opening degree (&thgr;ap), thereby compensating for an output shortage due to a response delay of the output from the Rankine cycle system. When the accelerator opening degree (&thgr;ap) commanded by the driver is decreased, the throttle opening degree (&thgr;th) is decreased by the correcting amount (&Dgr;&thgr;th) more than the value proportional to the accelerator opening degree (&thgr;ap), thereby compensating for an output excessiveness due to the response delay of the output from the Rankine cycle system.

Abstract: A hybrid vehicle includes: a metal V-belt type infinitely variable gear-change mechanism 20 whereby the rotation of an engine E is subjected to change in gear ratio, a forwards clutch 14 and a reverse brake 15 that perform engagement/disengagement control of the engine and the infinitely variable gear-change mechanism, and a second motor generator 50 capable of driving the drive wheels arranged parallel with the engine. The control device is provided with a first hydraulic pump 3 for engine drive, a second hydraulic pump 56 that is driven by an electric motor 55 for pump drive, and a forwards/reverse clutch control valve 73 that performs changeover control of supply of working hydraulic pressure to the forwards clutch 14 etc.

Abstract: The hybrid vehicle of the present invention has an internal combustion engine, a power storage unit for storing electric power, and a motor driven by the electric power stored in the power storage unit, the hybrid vehicle being driven by at least one of the outputs from the internal combustion engine and the motor.

Abstract: A hybrid vehicle includes: a metal V-belt type infinitely variable gear-change mechanism 20 whereby the rotation of an engine E is subjected to change in gear ratio, a forwards clutch 14 and a reverse brake 15 that perform engagement/disengagement control of the engine and the infinitely variable gear-change mechanism, and a second motor generator 50 capable of driving the drive wheels arranged parallel with the engine. The control device is provided with a first hydraulic pump 3 for engine drive, a second hydraulic pump 56 that is driven by an electric motor 55 for pump drive, and a forwards/reverse clutch control valve 73 that performs changeover control of supply of working hydraulic pressure to the forwards clutch 14 etc.

Abstract: A control system for a hybrid vehicle prevents a voltage across an electric energy storage device from dropping excessively when the electric energy storage device is discharged with a generator/motor operating as an electric motor, for thereby effectively utilizing electric energy stored in the electric energy storage device as much as possible to operate the generator/motor as the electric motor. The control system also prevents the voltage across the electric energy storage device from rising excessively when the electric energy storage device is charged with the generator/motor operating as an electric generator, for thereby charging the electric energy storage device with electric energy generated by the generator/motor as much as possible while protecting the electric energy storage device.

Abstract: A control system for a hybrid vehicle including a traction motor which drives a drive shaft of the vehicle by electrical energy and has a regenerative function of converting kinetic energy of the drive shaft into electrical energy, a transmission arranged between driving wheels of the vehicle and an internal combustion engine of the vehicle and the traction motor, and a storage battery which supplies electrical energy to the traction motor and stores electrical energy output from the traction motor. A desired output from the traction motor is calculated according to decelerating conditions of the vehicle, and an optimal rotational speed of the traction motor at which the traction motor provides a maximum regeneration output is calculated according to the calculated desired output. The change gear ratio of the transmission is controlled such that the rotational speed of the traction motor is equal to the optimal rotational speed.