Drive system for a motor vehicle with a drive unit and electric machine, and method of operating the system

• US 6,149,544 A
• Filed: 01/19/1999
• Issued: 11/21/2000
• Est. Priority Date: 08/31/1995
• Status: Expired due to Fees

• Current Assignee: Isad Electronic Systems GmbH & Co. KG
• Original Assignee: Grundl und Hoffman GmbH, Isad Electronic Systems GmbH & Co. KG
• Inventors: Hoffmann, Bernhard, Grundl, Andreas, Pels, Thomas, Masberg, Ullrich, Zeyen, Klaus-Peter
• Primary Examiner(s): Marmor, Charles A
• Assistant Examiner(s): PANG, ROGER L
• Application Number:
  US09/029,516
• Time in Patent Office: 672 Days
• Field of Search: 475/1, 475/5, 477/2, 477/3, 477/5, 477/6, 477/7, 477/8, 477/13, 180/65.2, 180/65.4
• US Class Current: 477/13
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/38 characterised by the driveline clutches shift clutches within the gearing or transmission B60K6/36 , B60K6/54
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• 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 2200/26 Rail vehicles
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2220/52 Clutch motors
• CPC Class Codes: B60L 2240/34 Cabin temperature
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2250/18 by enquiring driving style
• CPC Class Codes: B60L 2250/30 by voice
• CPC Class Codes: B60L 2270/145 Structure borne vibrations
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 2510/0657 : Engine torque
• CPC Class Codes: F02D 2250/24 : by using an external load, e.g. a generator
• CPC Class Codes: F02N 11/0818 : Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode
• CPC Class Codes: F02N 11/0822 : related to action of the driver
• CPC Class Codes: F02N 11/0825 : related to prevention of engine restart failure, e.g. disabling automatic stop at low battery state
• CPC Class Codes: F02N 11/0866 : comprising several power sources, e.g. battery and capacitor or two batteries
• CPC Class Codes: F02N 2011/0888 : DC/DC converters
• CPC Class Codes: F02N 2300/102 : Control of the starter motor speed; Control of the engine speed during cranking
• CPC Class Codes: F16H 2061/0422 : by an electric machine, e.g. by accelerating or braking the input shaft
• CPC Class Codes: H02K 51/00 : Dynamo-electric gears, i.e. dynamo-electric means for transmitting mechanical power from a driving shaft to a driven shaft and comprising structurally interrelated motor and generator parts
• CPC Class Codes: Y02T 10/40 : Engine management systems
• 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 903/906 : Motor or generator
• CPC Class Codes: Y10S 903/912 : Drive line clutch

Abstract

The invention concerns a drive system, especially for a motor vehicle, with a drive assembly, especially an internal combustion engine (1); and at least one electric machine (4), which acts as an electromagnetic coupling in the drive train (2) of the drive system and/or as an active transmission synchronization device. The invention is also oriented to a method of operating a drive system.

Claims

1. A drive system for a motor vehicle, comprising

a combustion engine (1) as the drive system,

a drive train (2) for torque transmission from the combustion engine (1) to drive wheels (3), with a drive shaft (10) driven by the combustion engine (1) and an output shaft (55),

a lock-up clutch (60) between the drive shaft (10) and the output shaft (55),

in the drive train (2), an electrical machine (4) which has at least two electromagnetic active units--a rotor (9) and a stator (8),

wherein the rotor (9) is connected with one of the two shafts--the output shaft (55) or the drive shaft (10)--in a rotationally fixed manner and the lock-up clutch (60) is arranged between the rotor (9) and the other of the two shafts (10 or 55, respectively), thereby rotating together with such shaft (10 or 55, respectively), and

wherein the stator (8,8'"'"') is provided as a double unit whose

i) first partial unit (8'"'"') is coupled in a rotationally fixed manner with the other of the two shafts (10 or 55, respectively), thereby rotating together with such shaft (10 or 55, respectively), and

ii) whose other partial unit (8) is not coupled with the other of the two shafts (10 or 55, respectively) and is thereby fixed against rotation,

wherein always one of the two partial units (8'"'"', 8) is electromagnetically activated and the other deactivated, and

wherein in case the first partial unit (8'"'"') is active and the lock-up clutch (60) is open, the combustion engine (1) transfers its torque to the drive wheels (3) via the electrical machine (4), with the latter then acting as an electromagnetic clutch,

wherein, in case the second partial unit (8'"'"') is active, the combustion engine (1) transfers its torque via the then closed lock-up clutch (60) to the drive wheels (3), with the electrical machine (4) additionally applying torque to the then connected drive and output shafts (10, 55).

2. A drive system for a motor vehicle, comprising

a combustion engine (1) as the drive system,

a drive train (2) for torque transmission from the combustion engine (1) to drive wheels (3) by means of a drive shaft (10) driven by the combustion engine (1) and an output shaft (55),

a lock-up clutch (60) between the drive shaft (10) and the output shaft (55),

an electrical machine (4) in the drive train (2) having at least two electromagnetic active units--a rotor (9) an a stator (8),

wherein the rotor (9) is connected with one of the two shafts--the output shaft (55) or the drive shaft (10)--in a rotationally fixed manner and the lock-up clutch (60) is arranged between the rotor (9) and the other of the two shafts (10 or 55, respectively), and

wherein the stator (8) is either

i) in a first coupling state in which it is coupled with the other of the two shafts (10 or 55, respectively) in a rotationally fixed manner, thereby rotating together with such shaft (10 or 55, respectively), or

ii) in another coupling state in which it is disengaged from the other of the two shafts (10 or 55, respectively) and fixed against rotation,

wherein the combustion engine (1) transfers its torque in the first coupling state and in case the lock-up clutch (60) is open to the drive wheels (3) via the electrical machine (4), with the latter then acting as an electromagnetic clutch, wherein, in the other coupling state, the combustion engine (1) transfers its torque via the then closed lock-up clutch (60) to the drive wheels (3), with the electrical machine (4) additionally applying torque to the then connected drive and output shafts (10, 55).

3. A drive system according to claim 2 wherein additional torque applied by the electrical machine (4) is a constant positive or negative or a varying torque.

4. A drive system according to claim 2 wherein the transition from the first to the other coupling state of the stator (8) is achieved by opening a clutch (63) between the stator (8) and the other of the two shafts (10 or 55, respectively) and closing a clutch (64) between the stator (8) and a housing (61).

5. A drive system according to claim 2 wherein the electrical machine (4) acts as a starter and/or transmission clutch.

6. A drive system according to claim 2 wherein the electrical machine (4) acts as a flywheel mass starter with an electromagnetically couplable flywheel mass.

7. A drive system according to claim 2 wherein the electrical machine (4) acts as an active transmission synchronization device.

8. A drive system according to claim 2 wherein the electrical machine (4) is a rotating field machine or a traveling field machine.

9. A drive system according to claim 2 comprising at least one inverter (17) to produce the voltages and/or currents with variable frequency, amplitude and/or phase required for the magnetic fields of the machine (4).

10. A drive system according to claim 2 wherein the electrical machine (4) has the additional function of actively reducing rotational fluctuations.

11. A drive system according to claim 10 wherein the electrical machine (4) produces a rapidly varying torque, i.e. a variable torque, which is in particular an alternating torque.

12. A drive system according to claim 11 wherein the electrical machine (4) superimposes the variable torque over a positive or negative torque, i.e. a constant torque.

13. A drive system according to claim 11 wherein the energy gained through clutch slip or the other decelerating constant torque and/or the energy gained during reduction of a positive rotational fluctuation is at least partially stored and reused.

14. A drive system according to claim 2 wherein the electrical machine (4) has the function of a direct starter and/or of a power supply generator.

15. A drive system according to claim 2 wherein the electrical machine (4) has a high torque density, compared with the maximum torque, in excess of 0.01 Nm/cm³.

16. A drive system according to claim 2 wherein, in the electrical machine (4), a mechanical clutch is integrated.

17. A drive system according to claim 2 with an acceleration slip control wherein the electrical machine (4) is arranged in such a way that drive slip reduction can be achieved by reducing the drive torque, i.e. by braking action and/or clutch slip action.

18. A procedure to operate a drive system for a motor vehicle, with a combustion engine (1) as the drive system, a drive train (2) for torque transmission from the combustion engine (1) to drive wheels (3), having a drive shaft (10) driven by the combustion engine (1) and an output shaft (55), with the following characteristics:

a lock-up clutch (60) is arranged between the drive shaft (10) and the output shaft (55),

in the drive train (2), an electrical machine (4) is arranged which has at least two electromagnetic active units--a rotor (9) and a stator (8), wherein the rotor (9) is connected with one of the two shafts--the output shaft (55) or the drive shaft (10)--in a rotationally fixed manner and the lock-up clutch (60) is positioned between the rotor (9) and the other of the two shafts (19¹ or 55, respectively), and

the stator (8) is operated either

i) in a first coupling state in which it is coupled with the other of the two shafts (10 or 55 respectively) in a rotationally fixed manner, thereby rotating together with such shaft (10 or 55, respectively), or

ii) in another coupling state in which it is uncoupled from the other of the two shafts (10 or 55, respectively) and fixed against rotation,

wherein the combustion engine (1) transfers its torque in the first coupling state and in case the lock-up clutch (60) is open to the drive wheels (3) via the electrical machine (4), with the latter then acting as an electromagnetic clutch,

wherein, in the other coupling state, the combustion engine (1) transfers its torque via the then closed lock-up clutch (60) to the drive wheels (3), with the electrical machine (4) additionally applying torque to the then connected drive and output shafts (10,

     55).

19. A procedure for operating a drive system for a motor vehicle, comprising a combustion engine (1) as the drive system, a drive train (2) for torque transmission from the combustion engine (1) to drive wheels (3) with a drive shaft (10) driven by the combustion engine (1) and an output shaft (55), with the following characteristics:

a lock-up clutch (60) is arranged between the drive shaft (10) and the output shaft (55),

in the drive train (2), an electrical machine (4) is arranged which has at least two electromagnetic active units--a rotor (9) and a stator (8), wherein the rotor (9) is connected with one of the two shafts--the output shaft (55) or the drive shaft (10)--in a rotationally fixed manner and the lock-up clutch (60) is arranged between the rotor (9) and the other of the two shafts (10 or 55, respectively), and

wherein the stator (8,8'"'"') is provided as a double unit whose

i) first partial unit (8'"'"') is coupled in a rotationally fixed manner with the two shafts (10 or 55, respectively), and

ii) whose other partial unit (8) is not coupled with the other of the two shafts (10 or 55, respectively) and rather fixed against rotation,

wherein always one of the two partial units (8'"'"',

     8) is electromagnetically activated and the other deactivated, and

wherein in case the first partial unit (8'"'"') is active and the lock-up clutch (60) is open, the combustion engine (1) transfers its torque to the drive wheels (3) via the electrical machine (4), with the latter then acting as an electromagnetic clutch,

wherein, in case the second partial unit (8'"'"') is active, the combustion engine (1) transfers its torque via the then closed lock-up clutch (60) to the drive wheels (3), with the electrical machine (4) additionally applying torque to the then connected drive and output shafts (10,

     55).