Drive control system for hybrid vehicles

• US 6,336,889 B1
• Filed: 09/28/2000
• Issued: 01/08/2002
• Est. Priority Date: 01/16/1998
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Endo, Hiroatsu, Oba, Hidehiro, Hoshiya, Kazumi, Nomoto, Hisanori
• Primary Examiner(s): Marmor, Charles A
• Assistant Examiner(s): PANG, ROGER L
• Application Number:
  US09/671,259
• Time in Patent Office: 467 Days
• Field of Search: 477/5, 477/175, 477/176, 477/167, 477/180
• US Class Current: 477/5
• CPC Class Codes: B60K 2006/268 Electric drive motor starts the engine, i.e. used as starter motor
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• 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 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2710/025 Clutch slip, i.e. difference between input and output speeds
• CPC Class Codes: B60W 30/18027 Drive off, accelerating from standstill
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y10S 903/903 having energy storing means, e.g. battery, capacitor
• CPC Class Codes: Y10S 903/91 Orbital, e.g. planetary gears
• CPC Class Codes: Y10S 903/917 with transmission for changing gear ratio
• CPC Class Codes: Y10S 903/946 Characterized by control of driveline clutch

Abstract

A drive control system for a hybrid vehicle in which an internal combustion engine is selectively coupled through a clutch mechanism to a power transmission line coupled to an electric motor. The drive control system comprises: motoring device for coupling the engine to the power transmission line to rotate the engine, with the feed of a fuel to the engine being stopped when the hybrid vehicle is driven to run by the output of the electric motor, by controlling the clutch mechanism in an applied state. Thus, it is possible to start the engine even at a low speed of the hybrid vehicle and to prevent the deterioration in the riding comfort, as might otherwise be caused by the fluctuation in a driving torque.

Claims

1. A drive control system for a hybrid vehicle in which an internal combustion engine is selectively coupled through a clutch mechanism to a power transmission line coupled to an electric motor, comprising:

motoring means for coupling said internal combustion engine to said power transmission line to rotate said internal combustion engine, with a feed of fuel to said internal combustion engine being stopped when said hybrid vehicle is driven to run by an output of said electric motor, by controlling said clutch mechanism in an applied state, and

motoring speed control means for limiting a speed of said internal combustion engine to a predetermined level when said internal combustion engine is rotated by the output of said electric motor,

wherein said motoring speed control means includes slip control means for setting said clutch mechanism in a partially applied state between a completely applied state and a completely released state.

2. A drive control system for a hybrid vehicle in which an internal combustion engine is selectively coupled through a clutch mechanism to a power transmission line coupled to an electric motor, comprising:

motoring means for controlling said clutch mechanism in an applied state to couple said internal combustion engine to said power transmission line at a starting time when said hybrid vehicle is started by the output of said electric motor;

speed detecting means for detecting that a speed of said internal combustion engine has reached a predetermined reference level;

ignition means for starting combustion of a fuel in said internal combustion engine when the speed detecting means detects that the speed of said internal combustion engine has reached said reference level; and

release means for releasing the coupling between said internal combustion engine and said power transmission line by said clutch mechanism after combustion of the fuel in said internal combustion engine is continuously started.

3. A drive control system for a hybrid vehicle according to claim 2, further comprising:

application control means for applying said released clutch mechanism again so that the speed of said internal combustion engine may take a predetermined level.

4. A drive control system for a hybrid vehicle according to claim 3,

wherein said application control means includes feedback control means for feedback-controlling the applied state of said clutch mechanism based on the speed of said internal combustion engine.

5. A drive control system for a hybrid vehicle according to claim 3, further comprising:

speed calculating means for calculating the speed of said started internal combustion engine based on a throttle opening or an accelerator opening,

wherein said application control means includes feedback control means for feedback-controlling a torque transmission capacity of said clutch mechanism based on the speed of said internal combustion engine so that the speed of said internal combustion engine may take a value calculated by said speed calculating means.

6. A drive control system for a hybrid vehicle in which an internal combustion engine is selectively coupled through a clutch mechanism to a power transmission line coupled to an electric motor, comprising:

speed detecting means for detecting that a speed of said internal combustion engine, as rotated by said electric motor after said hybrid vehicle was driven to run by the output of said electric motor, has reached a predetermined reference level;

ignition means for starting combustion of a fuel in said internal combustion engine when said speed detecting means detects that the speed of said internal combustion engine has reached said reference level; and

release means for releasing said clutch mechanism to release the coupling between said internal combustion engine and said power transmission line by said clutch mechanism after combustion of the fuel in said internal combustion engine is continuously started.

7. A drive control system for a hybrid vehicle according to claim 6, further comprising:

application control means for applying said released clutch mechanism again so that the speed of said internal combustion engine may take a predetermined level.

8. A drive control system for a hybrid vehicle according to claim 7,

wherein said application control means includes feedback control means for feedback-controlling an applied state of said clutch mechanism based on the speed of said internal combustion engine.

9. A drive control system for a hybrid vehicle according to claim 7, further comprising:

speed calculating means for calculating the speed of said started internal combustion engine based on a throttle opening or an accelerator opening,

wherein said application control means includes feedback control means for feedback-controlling a torque transmission capacity of said clutch mechanism based on the speed of said internal combustion engine so that the speed of said internal combustion engine may take the value calculated by said speed calculating means.