Control system for a vehicular drive unit

• US 5,801,499 A
• Filed: 07/08/1996
• Issued: 09/01/1998
• Est. Priority Date: 07/11/1995
• Status: Expired due to Term

• Current Assignee: Aisin AW Company Limited (Aisin Corp.)
• Original Assignee: Aisin AW Company Limited (Aisin Corp.)
• Inventors: Hara, Takeshi, Tanaka, Satoru, Watanabe, Manabu, Tsuzuki, Shigeo, Omote, Kenji
• Primary Examiner(s): Cabeca, John W.
• Application Number:
  US08/676,807
• Time in Patent Office: 785 Days
• Field of Search: 180/65.1, 180/65.2, 180/65.3, 180/65.4, 180/65.6, 290/50, 290/45, 290/34, 318/140, 318/141, 318/142, 318/145, 318/146, 318/150, 318/153, 318/156
• US Class Current: 318/141
• CPC Class Codes: B60K 6/22 characterised by apparatus, components or means specially adapted for HEVs
• CPC Class Codes: B60K 6/34 characterised by the absence of energy storing means
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/387 Actuated clutches, i.e. clutches engaged or disengaged by electric, hydraulic or mechanical actuating means
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/54 Transmission for changing ratio
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2240/24 Steering angle
• CPC Class Codes: B60L 2240/445 Temperature
• 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 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/18 including control of braking systems
• 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2510/068 Engine exhaust temperature
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2540/18 Steering angle
• CPC Class Codes: B60W 30/18027 : Drive off, accelerating from standstill
• CPC Class Codes: F02D 29/06 : peculiar to engines driving electric generators
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• 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: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y10S 903/91 : Orbital, e.g. planetary gears
• CPC Class Codes: Y10S 903/914 : Actuated, e.g. engaged or disengaged by electrical, hydraulic or mechanical means
• CPC Class Codes: Y10S 903/917 : with transmission for changing gear ratio
• CPC Class Codes: Y10S 903/945 : Characterized by control of gearing, e.g. control of transmission ratio
• CPC Class Codes: Y10S 903/946 : Characterized by control of driveline clutch
• CPC Class Codes: Y10S 903/947 : Characterized by control of braking, e.g. blending of regeneration, friction braking

Abstract

A control system for a vehicular drive unit that includes an engine, a motor-generator connected to the output shaft of the engine and which acts as both a motor and a generator, a battery for storing the energy recovered by the motor-generator as electric power and for feeding electric power to drive the motor-generator, a first clutch for connecting the motor-generator and the wheels, a stop state detector for detecting the stopped state of the vehicle, and a controller for controlling the engine, the motor-generator and the first clutch. When the stopped state is detected by the stop state detector, the controller releases the first clutch, interrupts the feed of fuel to the engine, and feeds electric power to the motor-generator to drive the motor-generator to thereby hold the rotation of the engine substantially at an idling RPM.

Claims

1. A control system for a vehicular drive unit, comprising:

an engine;

a motor-generator connected to the output shaft of said engine for acting as a motor and a generator;

a battery for storing the energy recovered by said motor-generator as electric power and for feeding electric power to drive said motor-generator;

a first clutch for connecting said motor-generator and the wheels;

stop state detecting means for detecting the stopped state of the vehicle; and

control means for controlling said engine, said motor-generator and said first clutch, wherein when the stopped state of the vehicle is detected by said stop state detecting means, said control means releases said first clutch, interrupts the feed of fuel to said engine, and feeds the electric power to said motor-generator to drive said motor-generator thereby to hold the rotation of said engine substantially at an idling RPM.

2. A control system according to claim 1, wherein said control means includes stop time metering means for metering the stop time period of the vehicle, to hold the rotation of said engine at a predetermined RPM smaller than an idling RPM when the stop time period is over a predetermined value.

3. A control system according to claim 1, further comprising residue detecting means for detecting the electric power residue of said battery, wherein when the stopped state of said vehicle is detected by said stop state detecting means and when the residue of said battery detected by said residue detecting means is over a predetermined value, said control means releases said first clutch, interrupts the feed of fuel to said engine and feeds electric power to said motor-generator to bring the motor-generator into a drive state thereby to hold the rotation of said engine substantially at the idling RPM.

4. A control system according to claim 1, further comprising a power steering switch for detecting the action of a power steering, wherein when the stopped state of said vehicle is detected by said stop state detecting means and when it is detected by said power steering switch that said power steering is inactive, said control means releases said first clutch, interrupts the feed of fuel to said engine and feeds electric power to said motor-generator to bring the same into a drive state thereby to hold the rotation of said engine substantially at the idling RPM.

5. A control system according to claim 1, further comprising a catalyst temperature sensor for detecting a catalyst temperature, wherein when the stopped state of said vehicle is detected by said stop state detecting means and when the catalyst temperature detected by said catalyst temperature sensor is over a predetermined value, said control means releases said first clutch, interrupts the feed of fuel to said engine and feeds electric power to said motor-generator to bring the motor-generator into a drive state thereby to hold the rotation of said engine substantially at the idling RPM.

6. A control system unit according to claim 1, further comprising a second clutch for connecting said engine and said motor-generator, wherein when the output signal detected by the brake sensor is switched from ON to OFF while said motor-generator is in the drive state, said control means reopens the feed of fuel to said engine, interrupts the drive of said motor-generator, releases said second clutch, brings said motor-generator into a generating state, and applies said first clutch.

7. A control system according to claim 1, further comprising a fluid coupling having a lockup clutch between said engine and said motor-generator, wherein when the stopped state of said vehicle is detected by said stop state detecting means, said control means releases said first clutch, applies said lockup clutch, interrupts the feed of fuel to said engine and feeds electric power to said motor-generator to bring the motor-generator into a drive state thereby to hold the rotation of said engine substantially at the idling RPM.

8. A control system according to claim 7, wherein when the output signal detected by the brake sensor is switched from ON to OFF while said motor-generator is in the drive state, said control means reopens the feed of fuel to said engine, interrupts the drive of said motor-generator, releases said lockup clutch, brings said motor-generator into a generating state, and applies said first clutch.

9. A control system for a vehicular drive unit, comprising:

an engine;

a motor-generator acting as a motor and a generator;

a planetary gear having at least three rotary elements, the first rotary element of said planetary gear being connected to the output shaft of said engine, the second rotary element being connected to said motor-generator to perform a reaction against said first rotary element, and the third rotary element being connected to an output member for transmitting power to wheels;

a battery for storing energy recovered by said motor-generator as electric power, and for feeding electric power to drive said motor-generator,

stop state detecting means for detecting a stopped state of the vehicle; and

control means for controlling said engine and said motor-generator, wherein when the stopped state of the vehicle is detected by said stop state detecting means, said control means interrupts the feed of fuel to said engine, and feeds the electric power to said motor-generator thereby to hold the rotation of said engine substantially at an idling RPM.

10. A control system according to claim 9, further comprising residue detecting means for detecting the electric power residue of said battery, wherein when the stopped state of the vehicle is detected by said stop state detecting means and when the residue detected by said residue detecting means is below a predetermined value, said control means feeds the fuel to said engine to hold the rotation of said engine at a predetermined RPM and causes said motor-generator to generate the electric power.

11. A control system according to claim 9, further comprising a catalyst temperature sensor for detecting a catalyst temperature, wherein when the stopped state of the vehicle is detected by said stop state detecting means and when the catalyst temperature detected by said catalyst temperature sensor is below a predetermined value, said control means feeds the fuel to said engine to hold the rotation of said engine substantially at an idling RPM.

12. A control system according to claim 9, further comprising brake control means for controlling the oil pressure of a brake, wherein when the stopped state of the vehicle is detected by said stop state detecting means, said brake control means holds said brake oil pressure over a predetermined value.