Power train with automated clutch for use in motor vehicles

• US 5,928,110 A
• Filed: 02/27/1998
• Issued: 07/27/1999
• Est. Priority Date: 02/27/1997
• Status: Expired due to Term

• Current Assignee: Schaeffler Technologies AG & Co.KG (INA-Holding Schaeffler GmbH & Co. KG)
• Original Assignee: Luk Getriebe-Systeme GmbH (INA-Holding Schaeffler GmbH & Co. KG)
• Inventors: Zimmermann, Martin, Vornehm, Martin
• Primary Examiner(s): Marmor, Charles A
• Assistant Examiner(s): ESTREMSKY, SHERRY LYNN
• Application Number:
  US09/032,648
• Time in Patent Office: 515 Days
• Field of Search: 477/114, 477/166, 477/174, 477/180, 477/906, 477/70, 477/79, 477/86
• US Class Current: 477/166
• CPC Class Codes: B60K 28/04 responsive to presence or absence of the driver, e.g. to weight or lack thereof
• 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 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 2050/0045 using databus protocols
• CPC Class Codes: B60W 2050/021 Means for detecting failure or malfunction
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2710/027 Clutch torque
• CPC Class Codes: B60W 30/18 Propelling the vehicle
• CPC Class Codes: B60W 30/18063 Creeping
• CPC Class Codes: B60W 50/02 Ensuring safety in case of control system failures, e.g. by diagnosing, circumventing or fixing failures
• CPC Class Codes: F16D 2500/1026 Hydraulic
• CPC Class Codes: F16D 2500/10412 Transmission line of a vehicle
• CPC Class Codes: F16D 2500/30401 On-off signal indicating the engage or disengaged position of the clutch
• CPC Class Codes: F16D 2500/3063 Engine fuel flow rate
• CPC Class Codes: F16D 2500/3065 Torque of the engine
• CPC Class Codes: F16D 2500/3067 Speed of the engine
• CPC Class Codes: F16D 2500/30806 : Engaged transmission ratio
• CPC Class Codes: F16D 2500/30816 : Speed of the input shaft
• CPC Class Codes: F16D 2500/3108 : Vehicle speed
• CPC Class Codes: F16D 2500/3144 : Accelerator pedal position
• CPC Class Codes: F16D 2500/31466 : Gear lever
• CPC Class Codes: F16D 2500/3148 : Detection of user presence
• CPC Class Codes: F16D 2500/50206 : Creep control
• CPC Class Codes: F16D 2500/50287 : Torque control
• CPC Class Codes: F16D 2500/50858 : Selecting a Mode of operation
• CPC Class Codes: F16D 2500/5102 : Detecting abnormal operation, e.g. unwanted slip or excessive temperature
• CPC Class Codes: F16D 2500/5108 : Failure diagnosis
• CPC Class Codes: F16D 2500/5114 : Failsafe
• CPC Class Codes: F16D 2500/7044 : Output shaft torque
• CPC Class Codes: F16D 48/06 : Control by electric or electronic means, e.g. of fluid pressure
• CPC Class Codes: F16D 48/066 : Control of fluid pressure, e.g. using an accumulator F16D48/062, F16D48/068 take precedence
• CPC Class Codes: F16H 61/12 : Detecting malfunction or potential malfunction, e.g. fail safe in control of hydrostatic gearing F16H61/4192; Circumventing or fixing failures
• CPC Class Codes: F16H 63/46 : Signals to a clutch outside the gearbox
• CPC Class Codes: Y10S 477/906 : Means detecting or ameliorating the effects of malfunction or potential malfunction

Abstract

The power train of a motor vehicle has an electronic unit which controls the condition of an automated clutch between the engine and a manually shiftable transmission. The control unit has a normal or standard operating mode when the various sensors which are connected with and transmit signals to the control unit (as well as the signal transmitting connections such as buses and/or cables) are not defective, and a standby or emergency mode when one or more sensors and/or connections are (temporarily or irreversibly) defective. The control unit then prevents the clutch from permitting or causing a creeping or crawling movement of the vehicle while the engine is idling and the transmission is shifted in a gear other than neutral. The mode of operation of the control unit can be changed back to normal in response to termination of a faulty operation of one or more sensors and/or connections, for example, with a predetermined delay.

Claims

1. A power train for use in a motor vehicle, comprising:

a prime mover;

means for starting, operating and arresting said prime mover;

a transmission arranged to receive torque from said prime mover and being shiftable into and from a plurality of gears in which said transmission tends to move the vehicle, said transmission including multiple-position means for selecting gears and for shifting into and from selected gears;

an automated system arranged to transmit torque from said prime mover to said transmission and having engaged and disengaged conditions; and

means for controlling said system, including a signal receiving, processing and transmitting control unit, an actuator arranged to select the magnitude of torque being transmitted by said system in response to processed signals from said control unit, a plurality of signal generating sensors, and means for transmitting signals from said sensors to said control unit, said sensors and said signal transmitting means being prone to malfunction and said control unit having a normal operating mode when said sensors and said signal transmitting means function properly, when said transmission receives torque from said system and when said transmission is shifted into one of said gears to thus move the vehicle, said control unit further having an emergency operating mode which is set up in response to malfunctioning of at least one of said sensors and said signal transmitting means and in which the vehicle is not set in motion while said prime mover is in operation and said transmission is shifted into one of said gears.

2. The power train of claim 1, wherein said prime mover comprises a fuel-consuming combustion engine and the vehicle comprises a multi-position throttle valve associated with the engine, a multi-position fuel consumption regulator associated with the engine, and at least one multi-position brake, said sensors including a sensor arranged to monitor the positions of said throttle valve, at least one sensor arranged to monitor the positions of said regulator, and at least one sensor arranged to monitor the positions of said gear selecting and shifting means.

3. The power train of claim 2, wherein said sensors further comprise at least one sensor arranged to monitor the positions of said at least one brake.

4. The power train of claim 2, wherein said sensors further comprise an electronic circuit for said engine, said circuit including at least one of said starting, operating and arresting means.

5. The power train of claim 2, wherein the vehicle comprises antiblocking means for said at least one brake and said sensors further comprise an electronic circuit for said antiblocking means.

6. The power train of claim 2, wherein said means for transmitting signals to said control unit comprises at least one bus.

7. The power train of claim 2, wherein said means for transmitting signals to said control unit comprises electrical conductor means.

8. The power train of claim 2, wherein the positions of said fuel consumption regulator include an idle position and the vehicle performs a crawling movement in said normal operating mode of said control unit while said regulator assumes said idle position.

9. The power train of claim 2, wherein said positions of said fuel consumption regulator include an idle position and the vehicle is not set in motion in said emergency operating mode of said control unit while said regulator assumes said idle position.

10. The power train of claim 9, wherein said transmission is arranged to set the vehicle in motion in the emergency mode of said control unit in response to movement of said regulator from said idle position.

11. The power train of claim 10, wherein the vehicle is set in motion in the emergency mode of said control unit and in response to movement of said regulator from said idle position in dependency upon at least one of a plurality of variable parameters of the vehicle.

12. The power train of claim 11, wherein said parameters include at least one of:

the RPM of the engine, the angle of a pivotable component of said throttle valve, the torque being transmitted by the engine, the position of said fuel consumption regulator, the timing of ignition of the engine, the timing of fuel injection into the engine, the quantity of fuel being supplied to the engine, the RPM of a rotary component of said transmission, the speed of the vehicle, the selected gear of said transmission, the position of said at least one brake, and the difference between the engine RPM and the transmission RPM.

13. The power train of claim 2, wherein at least one of said sensors and said signal transmitting means is prone to temporary malfunction and said control unit is arranged to reassume said normal mode in response to a termination of said temporary malfunction in the absence of at least one of (a) a full engagement of said system, (b) a full disengagement of said system, and (c) a shifting of said transmission out of gear.

14. The power train of claim 2, wherein at least one of said sensors and said signal transmitting means is prone to temporary malfunction and said control unit is arranged to reassume said normal mode in response to a termination of said temporary malfunction in the presence of at least one of (a) a full engagement of said system, (b) a full disengagement of said system, and (c) while said transmission is shifted into a neutral gear.

15. The power train of claim 2, wherein at least one of said sensors and said signal transmitting means is prone to temporary malfunction and said control unit is arranged to reassume said normal mode in response to a termination of said temporary malfunction and with a predetermined delay following such termination.

16. The power train of claim 2, wherein at least one of said sensors and said signal transmitting means is prone to temporary malfunction and said control unit is arranged to reassume said normal mode in response to a termination of said temporary malfunction and while receiving signals from at least one sensor other than said at least one of said sensors.

17. The power train of claim 16, wherein said at least one other sensor is at least one of (a) a sensor which monitors the positions of said at least one brake, (b) a sensor which generates a signal in response to detected presence of an operator in the motor vehicle, (c) said a least one sensor which is arranged to monitor the positions of said gear selecting and shifting means, (d) a sensor which monitors the positions of at least one openable and closable door forming part of the motor vehicle, (e) at least one sensor arranged to monitor the speed of the motor vehicle, and (f) a sensor constituting or forming part of an electronic control circuit for said engine.

18. The power train of claim 2, wherein at least one of said sensors and said signal transmitting means is prone to temporary malfunction and said control unit is arranged to reassume said normal mode in response to a termination of said temporary malfunction and subsequent to reception of a fresh signal subsequent to termination of said temporary mafunction.

19. The power train of claim 18, wherein said fresh signal is transmitted by a sensor other than said at least one sensor which is prone to said temporary malfunction.

20. The power train of claim 19, wherein said other sensor is at least one of (a) a sensor which monitors the position of said at least one brake, (b) a sensor which generates a signal in response to detected presence of an operator in the motor vehicle, (c) said at least one sensor which is arranged to monitor the positions of said gear selecting and shifting means, (d) a sensor which monitors the positions of at least one openable and closable door forming part of the motor vehicle, (e) at least one sensor arranged to monitor the speed of the motor vehicle, and (f) a sensor constituting or forming part of an electronic control circuit for said engine.

21. The power train of claim 2, wherein the vehicle comprises an openable and closable hood, an openable and closable trunk and an openable and closable door and first, second and third additional sensors arranged to transmit to said control unit signals denoting the positions of said hood, said trunk and said door, at least one of said sensors and said signal transmitting means being prone to temporary malfunction and said control unit being arranged to reassume said normal mode in response to a termination of said temporary malfunction and in response to transmission by said additional sensors of signals denoting that said hood, said trunk and said door are closed.

22. The power train of claim 1, wherein said controlling means comprises means for converting analog signals from at least one of said sensors into non-analog signals.

23. The power train of claim 22, wherein said non-analog signals are digital signals.

24. The power train of claim 22, wherein said non-analog signals are binary signals.

25. The power train of claim 22, wherein said means for transmitting signals comprises at least one bus arranged to transmit said non-analog signals from said at least one sensor to said control unit.

26. The power train of claim 22, wherein said means for converting comprises an electronic circuit.

27. The power train of claim 26, wherein said at least one sensor comprises a housing and said electronic circuit is confined in said housing.

28. The power train of claim 26, further comprising a first housing for said at least one sensor and a second housing for said electronic circuit.

29. A method of operating a power train for use in a motor vehicle wherein a fuel consuming prime mover which is arranged to be started, operated and arrested serves to transmit torque to a transmission which is shiftable into and from a plurality of gears in which the transmission tends to move the vehicle in response to at least partial engagement of an automated torque transmitting clutch which is controlled by a system including a signal receiving, processing and transmitting control unit, an actuator operable to select the magnitude of torque being transmitted by the clutch in response to processed signals from the control unit, and a plurality of sensors which are arranged to transmit signals to the control unit and at least one of which is prone to malfunction, comprising the step of changing, in response to malfunctioning of the at least one sensor, the mode of operation of the control unit from a normal mode in which the transmission moves the vehicle in an at least partially engaged condition of the clutch, while the prime mover is in the process of transmitting torque to the clutch and while the transmission is in gear, to an emergency mode in which the transmission is prevented from moving the vehicle while the transmission is in gear, the prime mover is operated and a member which is actuatable to increase the consumption of fuel by the prime mover is not actuated.

30. The method of claim 29, further comprising the step of setting the vehicle in motion by way of the engaged clutch and the transmission upon termination of a temporary malfunction of the at least one sensor.