Hybrid car

• US 7,441,617 B2
• Filed: 01/06/2006
• Issued: 10/28/2008
• Est. Priority Date: 03/19/1998
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Shiraishi, Takuya, Nogi, Toshiharu, Oosuga, Minoru, Tokuyasu, Noboru, Nakayama, Yoko
• Primary Examiner(s): Ellis; Christopher
• Assistant Examiner(s): WALTERS, JOHN DANIEL
• Application Number:
  US11/326,458
• Publication Number:
  US 20060113130A1
• Time in Patent Office: 1,026 Days
• Field of Search: 180/65.1, 180/65.2, 180/65.3, 180/65.4, 903/940, 903/941, 701/22
• US Class Current: 180/65.235
• CPC Class Codes: B60K 2001/003 with means for cooling the electrical propulsion units
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60L 50/15 with additional electric power supply with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2510/0604 Throttle position
• CPC Class Codes: B60W 2510/305 Power absorbed by auxiliaries
• CPC Class Codes: B60W 2710/0622 Air-fuel ratio
• CPC Class Codes: B60W 2710/105 Output torque
• CPC Class Codes: F01N 2570/04 Sulfur or sulfur oxides
• CPC Class Codes: F01N 3/0842 Nitrogen oxides
• CPC Class Codes: F02D 2250/24 by using an external load, e.g. a generator
• CPC Class Codes: F02D 41/028 Desulfurisation of NOx traps or adsorbent
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y10S 903/945 : Characterized by control of gearing, e.g. control of transmission ratio

Abstract

By a lean burn operation, a highly efficient operation region is enlarged, the proportion of engine operation in a low torque condition is increased, and the proportion of motor operation using a battery is decreased. It is possible to provide a hybrid car of an engine-electric motor configuration which can effect a highly efficient operation without increasing the capacity of motor and that of battery.

Claims

1. A hybrid car controlling apparatus, comprising a controlling unit which is mounted on a hybrid car having an engine to vary air/fuel ratio of said engine and a motor, and to control a throttle valve drive for controlling an amount of air supplied to said engine, an injector drive for supplying fuel to said engine and a drive of a motor, such that

(a) when a drive-requiring torque value obtained according to an operation condition of said hybrid car is smaller than a predetermined torque value, said motor drive is controlled to drive said hybrid car according to said motor;

and

(b) when said drive-requiring torque value is larger than said predetermined torque value, said throttle valve is opened, and said air/fuel ratio is made larger than a stoichiometric value, with said throttle valve drive and said injector drive being controlled to drive said hybrid car according to said engine.

2. A hybrid car system on a hybrid car having an engine in which an air/fuel ratio of said engine is varied as a function of vehicle driving power,

the hybrid car system comprising:

a motor for constituting said vehicle driving power together with said engine;

an inverter for controlling a drive of said motor;

a throttle valve for controlling an amount of air supplied to said engine;

an injector for supplying fuel to said engine; and

a unit operative to control a throttle valve drive and an injector drive, wherein

said unit is operative to control said motor drive, said throttle valve drive and said injector drive to run said hybrid car by changing over at least a first operation area, a second operation area and a third operation area in response to an operation condition of said vehicle;

said first operation area is an area in which said vehicle is driven according to said motor;

said second operation area is an area for changing over from said first operation area and said vehicle is driven according to said engine by making a degree of said throttle valve opening at an open condition, and making said air/fuel ratio of said engine larger than a stoichiometric value; and

said third operation area is an area for changing over from said second operation area and said vehicle is driven according to said engine by making said air/fuel ratio said stoichiometric value.

3. A hybrid car system on a hybrid car having an engine in which an air/fuel ratio of said engine is varied as a function of vehicle driving power,

the hybrid car system comprising:

a motor for constituting said vehicle driving power together with said engine;

an inverter for controlling a drive of said motor;

a throttle valve for controlling an amount of air supplied to said engine;

an injector for supplying fuel to said engine; and

a unit operative to control a throttle valve drive and an injector drive, wherein

said unit is operative to control a said motor drive, said drive of said throttle valve and said injector drive to run said hybrid car by changing over at least a first operation area, a second operation area and a third operation area in response to an operation condition of said vehicle;

said first operation area is an area in which said vehicle is driven according to said motor;

said second operation area is an area for changing over from said first operation area and said vehicle is driven according to said engine by flowing back exhaust gas into cylinders of said engine; and

said third operation area is an area for changing over from said second operation area and said vehicle is driven according to said engine by bringing said air/fuel ratio to a stoichiometric value.

4. A hybrid car system according to claim 3, wherein, when said air/fuel ratio is brought to said stoichiometric value, said exhaust gas is flown back into said cylinders.

5. A hybrid car system according to claim 3, wherein, when said exhaust gas is flown back into said cylinders, a swirl in said cylinders is made to occur.

6. A hybrid car system according to claim 4, wherein, when said exhaust gas is flown back into said cylinders, a swirl in said cylinders is made to occur.

7. A hybrid car system according to claim 3, wherein, when said exhaust gas is flown back into said cylinders, a stratification combustion in said cylinders occurs in which an air-fuel mixture is gathered at a surrounding portion of an ignition plug of said engine.

8. A hybrid car system on a hybrid car having an engine in which an air/fuel ratio of said engine is varied as a function of vehicle driving power,

the hybrid car system comprising:

a motor for constituting said vehicle driving power together with said engine;

an inverter for controlling a drive of said motor;

a throttle valve for controlling an amount of air supplied to said engine;

an injector for supplying fuel to said engine; and

a unit operative to control a throttle valve drive and an injector drive, wherein

said unit is operative to control said motor drive, said throttle valve drive and said injector drive to run said hybrid car by changing over at least a first operation area, a second operation area and a third operation area in response to an operation condition of said vehicle;

said first operation area is an area in which said vehicle is driven according to said motor;

said second operation area is an area for changing over from said first operation area and said vehicle is driven according to said engine by controlling an intake air valve timing of said engine; and

said third operation area is an area for changing over from said second operation area and said vehicle is driven according to said engine by making said air/fuel ratio engine a stoichiometric value.

9. A hybrid car having an engine, in which an air/fuel ratio is varied, and a motor constituting a driving power for running the hybrid car by changing over at least a first operation area, a second operation area and a third operation area in response to an operation condition of said hybrid car, wherein

said first operation area is an area in which said hybrid car is driven according to said motor;

said second operation area is an area for changing over from said first operation area and said hybrid car is driven according to said engine by flowing-back exhaust gas into cylinders of said engine; and

said third operation area is an area for changing over from said second operation area and said hybrid car is driven according to said engine by making an air/fuel ratio a stoichiometric value.

10. A hybrid car according to claim 9, wherein, when said air/fuel ratio is brought to said stoichiometric value, said exhaust gas is flown back into said cylinders.

11. A hybrid car according to claim 9, wherein, when said exhaust gas is flown back into said cylinders, a swirl is made to occur in said cylinders.

12. A hybrid car according to claim 10, wherein, when said exhaust gas is flown back into said cylinders, a swirl is made to occur in said cylinders.

13. A hybrid car according to claim 9, wherein, when said exhaust gas is flown back into said cylinders, a stratification combustion occurs in said cylinders in which said air-fuel mixture is gathered at a surrounding portion of an ignition plug of said engine.

14. A hybrid car having an engine, in which an air/fuel ratio is varied, and a motor constituting a driving power for running the hybrid car by changing over at least a first operation area, a second operation area and a third operation area in response to an operation condition of said hybrid car, wherein

said first operation area is an area in which said hybrid car is driven according to said motor;

said second operation area is an area for changing over from said first operation area and said hybrid car is driven according to said engine by controlling an intake air valve timing of said engine; and

said third operation area is an area for changing over from said second operation area and said hybrid car is driven according to said engine by bringing an air/fuel ratio of said engine to a stoichiometric value.

15. In a hybrid car comprising a cylinder-direct fuel injection engine enable for performing a lean bum operation by controlling an air fuel ratio between an air inhaled in a cylinder through a throttle valve and an intake valve and a fuel injected directly to said cylinder through an injection and a motor driven by an power source as a battery connected electrically to said engine through an inverter, said engine and said motor being as a driving source of a vehicle, wherein

where an output smaller than an output of said engine in an engine operating area is required to drive said vehicle according to said output of said engine, said motor is driven to output an output smaller than said output of said engine from said motor,

at said engine operation area, said throttle valve is opened, said engine is driven to perform said lean burn operation by enlarging said air/fuel ratio than a stoichiometric value, by forming a fluidization of an air-fuel mixture of said air and said fuel in said cylinder to make a swirl flow and by stratification combusting and stoichiometric operation becoming a stoichiometric value as said air/fuel ratio in accordance with an output of said engine necessary to drive said vehicle, and

at said lean burn operation time, in response to an output of said engine necessary for the drive of said vehicle, said engine is driven to vary said air/fuel ratio between a first air/fuel ratio larger than said stoichiometric value and a second air/fuel ratio larger than said stoichiometric value and also smaller than said first air/fuel ratio.

16. A hybrid car according to claim 15, wherein

at said lean burn operation time, said air/fuel ratio is varied linearly.

17. hybrid car according to claim 15, wherein

at said lean burn operation time, said air/fuel ratio is varied stepwise and said motor is operated, thereby a torque of said motor is adjusted.

18. A hybrid car according to claim 15, wherein

the hybrid car comprises a means for judging an indication of a driver from data including at least an acceleration pedal opening degree, and

an operating point of said engine is controlled awarding to a judgment of said judgment means.

19. A hybrid car according to claim 18, wherein

upon said judgment means judging as an operation performance to be important, said operation point of said engine is controlled to secure an allowance torque for performing an acceleration.

20. A hybrid car according to claim 15, wherein

deceleration occurs at an operating condition in which said throttle valve opening degree is large, said motor is operated as a generator, and said throttle valve or said air intake valve is closed.

21. A hybrid car according to claim 15, wherein

at said lean burn operation time, an exhaust gas of said engine is circulated into said cylinder.

22. A hybrid car according to claim 15, wherein

at said stoichiometric operation time, an exhaust gas of said engine is circulated into said cylinder.

23. A hybrid car according to claim 21, wherein

at a circulation flow of said exhaust gas, a fluidization in said cylinder is caused to form a swirl flow.

24. A hybrid car according to claim 21, wherein

at a circulation flow of said exhaust gas, a fluidization in said cylinder is caused to form a swirl flow.

25. A hybrid car according to claim 22, wherein

at a circulation flow of said exhaust gas, a fluidization in said cylinder is caused to form a swirl flow.

26. A hybrid car according to claim 23, wherein

at said circulation flow of said exhaust gas, a fluidization in said cylinder is caused to form a swirl flow.

27. A hybrid car according to claim 21, wherein at said circulation flow of said exhaust gas, an air-fuel mixture of said air and said fuel is gathered and combusted to a surrounding portion of an ignition plug, and a stratification combustion is performed.

28. A hybrid car system having a cylinder-direct fuel injection engine in which a lean burn operation is enabled to perform by controlling an air/fuel ratio, comprising

said cylinder-direct fuel injection engine being configured to perform a lean burn operation by controlling an air/fuel ratio,

a motor for constituting a driving source of a vehicle with said engine, an inverter for controlling a drive of said motor,

a battery being a power source of said motor and connected electrically said motor through said inverter,

an injector being provided for injecting directly a fuel into said cylinder, and

means for controlling a drive of said motor, a drive of said throttle valve, and a drive of said injector, wherein

said control means controls (1) a drive of said motor, when a case where an output smaller than an output of said engine in an engine operating area is required to drive said vehicle according to said output of said engine to output an output smaller than said output of said engine from said motor, (2) a drive of said throttle valve and a drive of said injector, at said engine operation area, said throttle valve is opened, said engine is driven to perform said lean burn operation by enlarging said air/fuel ratio than a stoichiometric value, by forming a fluidization of an air-fuel mixture of said air and said fuel in said cylinder to form a swirl flow and by stratification combusting and stoichiometric operation becoming stoichiometric value as said air/fuel ratio in accordance with an output of said engine necessary to drive said vehicle, and (3) said drive of said throttle valve and said drive of said injector, at said lean burn operation time, in response to an output of said engine necessary for the drive of said vehicle, said engine is driven to vary said air/fuel ratio between a first air/fuel ratio larger than said stoichiometric value and a second air/fuel ratio larger than said stoichiometric value and also smaller than said first air/fuel ratio.

29. In a hybrid car control means mounted on a hybrid car which has a cylinder-direct fuel injection engine enabled for a lean burn operation by controlling an air-fuel ratio between an air inhaled in a cylinder through a throttle valve and an intake valve and a fuel injected directly to said cylinder through an injection, a motor driven by an power source as a battery connected electrically to said motor through an inverter as a driving source of a vehicle, and

means mounted on said hybrid car for controlling a drive of said throttle valve, a drive of said injector, and a drive of said motor,

the hybrid car control means comprising

where an output smaller than an output of said engine in an engine operating area is required to drive said vehicle according to said output of said engine, and said motor is driven to output an output smaller than said output of said engine from said motor,

at said engine operation area, said throttle valve is opened, said engine is driven to perform said lean burn operation by enlarging said air/fuel ratio than a stoichiometric value, by forming a fluidization of an air-fuel mixture of said air and said fuel in said cylinder to form a swirl flow and by stratification combusting and stoichiometric operation becoming a stoichiometric value as said air/fuel ratio in accordance with an output of said engine necessary to drive said vehicle, and

at said lean burn operation time, in response to an output of said engine necessary for the drive of said vehicle, said engine is driven to vary said air/fuel ratio between a first air/fuel ratio larger than said stoichiometric value and a second air/fuel ratio larger than said stoichiometric value and also smaller than said first air/fuel ratio.