WO2002008011A1 - Calculation of automated friction clutch urge torque on grades - Google Patents

Calculation of automated friction clutch urge torque on grades Download PDF

Info

Publication number
WO2002008011A1
WO2002008011A1 PCT/IB2001/001323 IB0101323W WO0208011A1 WO 2002008011 A1 WO2002008011 A1 WO 2002008011A1 IB 0101323 W IB0101323 W IB 0101323W WO 0208011 A1 WO0208011 A1 WO 0208011A1
Authority
WO
WIPO (PCT)
Prior art keywords
vehicle
torque
urge
clutch
engine
Prior art date
Application number
PCT/IB2001/001323
Other languages
French (fr)
Inventor
Martin Fowler
Alfred John Richardson
Robert Stanley Wheeler
Keith Wright
Original Assignee
Eaton Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Eaton Corporation filed Critical Eaton Corporation
Priority to JP2002513723A priority Critical patent/JP2004504217A/en
Priority to DE60125370T priority patent/DE60125370T2/en
Priority to BRPI0113014-5A priority patent/BR0113014B1/en
Priority to AU2002224540A priority patent/AU2002224540A1/en
Priority to US10/333,163 priority patent/US7041031B2/en
Priority to EP01984323A priority patent/EP1303422B1/en
Publication of WO2002008011A1 publication Critical patent/WO2002008011A1/en

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00Conjoint control of vehicle sub-units of different type or different function
    • B60W10/04Conjoint control of vehicle sub-units of different type or different function including control of propulsion units
    • B60W10/06Conjoint control of vehicle sub-units of different type or different function including control of propulsion units including control of combustion engines
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00Conjoint control of vehicle sub-units of different type or different function
    • B60W10/02Conjoint control of vehicle sub-units of different type or different function including control of driveline clutches
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00Conjoint control of vehicle sub-units of different type or different function
    • B60W10/04Conjoint control of vehicle sub-units of different type or different function including control of propulsion units
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00Conjoint control of vehicle sub-units of different type or different function
    • B60W10/10Conjoint control of vehicle sub-units of different type or different function including control of change-speed gearings
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W30/00Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
    • B60W30/18Propelling the vehicle
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W30/00Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
    • B60W30/18Propelling the vehicle
    • B60W30/18009Propelling the vehicle related to particular drive situations
    • B60W30/18063Creeping
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W30/00Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
    • B60W30/18Propelling the vehicle
    • B60W30/1819Propulsion control with control means using analogue circuits, relays or mechanical links
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W50/00Details of control systems for road vehicle drive control not related to the control of a particular sub-unit, e.g. process diagnostic or vehicle driver interfaces
    • B60W2050/0001Details of the control system
    • B60W2050/0043Signal treatments, identification of variables or parameters, parameter estimation or state estimation
    • B60W2050/0044In digital systems
    • B60W2050/0045In digital systems using databus protocols
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W2530/00Input parameters relating to vehicle conditions or values, not covered by groups B60W2510/00 or B60W2520/00
    • B60W2530/10Weight
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W2552/00Input parameters relating to infrastructure
    • B60W2552/15Road slope, i.e. the inclination of a road segment in the longitudinal direction
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W30/00Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
    • B60W30/18Propelling the vehicle
    • B60W30/18009Propelling the vehicle related to particular drive situations
    • B60W30/18109Braking
    • B60W30/18118Hill holding
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S477/00Interrelated power delivery controls, including engine control
    • Y10S477/90Control signal is vehicle weight
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S477/00Interrelated power delivery controls, including engine control
    • Y10S477/901Control signal is slope

Definitions

  • This invention relates to improvements in vehicle transmissions, in particular to vehicles fitted with automated transmissions and clutch systems.
  • An Automated Mechanical Transmission includes a change gear transmission and normally also includes a Central Processing Unit (CPU) which controls the selection of gear and the operation of the gear selector mechanism.
  • CPU Central Processing Unit
  • an AMT is coupled to a conventional friction clutch, rather than a known hydraulic torque converter.
  • the clutch control is also automated and the driver has only two pedals in the cab, a throttle control or accelerator pedal and a brake pedal. Normal or manually operated clutches control the clutch and do not present the driver with an "urge to move" feeling. When stationary, the clutch is normally completely disengaged in order to minimise the clutch wear and avoid excessive heat dissipation that would arise from a continually slipping clutch. In these conditions there is nothing to prevent a vehicle fitted with an AMT rolling forwards or backwards if the driver has not applied either the parking brake or service brake using the pedal.
  • CPU Central Processing Unit
  • the expression "urge to move” is intended to mean that a vehicle is ready to move and the drive line slack has been taken up and there is a sensation given to the driver that the vehicle will move off if the brakes are released. It does not necessarily mean that the vehicle will creep forward (or backwards), as would tend to be the case, for a vehicle fitted with a conventional torque converter, but it is intended to indicate that sufficient torque is being transmitted through the vehicle drive-line to take up any slack in the drive-line components and that the vehicle will not just roll in a downhill direction if it is at rest on a gradient without a brake applied.
  • the Urge Torque is the amount of torque required to give the urge to move feeling and make the vehicle feel as if it is ready to move off from rest. It is an empirically determined figure that will depend on the weight and type of vehicle. It can be qualitatively described as the amount of torque needed to provide the driver with the sensation that at least any slack in the drive-line has been partially taken up and the clutch engagement process has started and so the vehicle is ready to move off.
  • Allowing the partial engagement of the clutch to provide slip under zero speed conditions partially replicates the sensations of a torque converter type system and provides the urge to move feeling experienced with such systems.
  • An automated clutch system can be programmed to transmit a greater amount of torque and so provide a limited amount of movement' and so replicate the "creep" function.
  • a hill holding capability in which the vehicle can be held stationary by the engine running at or slightly above idle speed and slipping clutch without the need for application of an additional braking force. It is also clear that when a vehicle is laden the amount of torque required to prevent the vehicle rolling backwards is greater than that required when it is unladen or on a flat or level surface.
  • an automated friction clutch adapted to be fitted to a vehicle and engageable to transfer power from an engine to a mechanical change gear transmission and a central processing unit for controlling operation of the clutch, and capable of sending command signals to the engine and transmission, a plurality of sensors, whose outputs are supplied as inputs to the central processing unit (CPU) for use in calculating the gradient on which the vehicle is operating and the weight of the vehicle, the calculated values of gradient and vehicle weight being used by the central processing unit to calculate a value of modified urge torque and to provide command signals to the engine to deliver to the clutch a torque output equal to the modified urge torque and to a clutch operator to engage to said clutch to the transmit the modified urge torque.
  • CPU central processing unit
  • Figure 1 shows a general schematic view of a transmission system
  • Figure 2 shows a flow chart for the operation of a logic sequence for operation of a transmission in the mode described.
  • Figure 1 shows a transmission system 10 includes an engine E having an output shaft 12 connected to a clutch C, which is in turn connectable to an input shaft 16 of a change gear transmission 11.
  • the transmission 11 is has an output shaft 20 connected to the drive wheels (not shown) of the vehicle.
  • the transmission system is controlled by a central processing unit (CPU) 30, which preferably is a single processing unit, but alternatively could be a plurality of processing units distributed processing units. In such circumstances the processing units may be located on the transmission, in the vehicle cab, on the engine, on the chassis or any combination of these.
  • CPU central processing unit
  • the transmission will normally have a number of modes in which it can operate, including manual and automatic. There may be additional functions to enable the shift points to be adjusted to suit the prevailing conditions.
  • the engine power demanded by a driver is signaled by TFf 22, whose output signal is sent to the CPU 30.
  • the CPU 30 then communicates the demanded power as an output signal to the engine E along link 23.
  • the driver will also be provided with a gear ratio selector lever 34, usable to select a transmission ratio or to override the selection made by the CPU if the transmission is in automatic mode. Operation of the clutch is controlled by the CPU whose control signals are sent to a clutch operator 27. Operation of the transmission will be by known means not forming a part of this invention.
  • the gear ratio selector lever 34 operates a set of contacts in unit 36 to provide an output signal to the CPU 30.
  • the selector lever 34 is used by the driver to select a gear ratio or to override the ratio selected by the transmission CPU. Further inputs to the CPU are from sensors ES, IS and OS which measure engine speed, transmission input shaft speed and transmission output shaft speed respectively. Output shaft speed can be used to determine vehicle speed in known manner.
  • the transmission controller 29 will also supply information about the currently engaged gearratio (GR). From this information, it is possible to calculate GNW in known manner. Another source of GVW information could be the SAE J1939 data-link or "CAN bus" system if one of these is fitted to the vehicle.
  • FIG. 2 shows a flow chart sequence for implementation of the present invention.
  • Values of throttle position THL, output shaft speed OS, engine speed ES and input shaft speed IS are taken from the sensors 22, 25, 28, and 30 and supplied to .the CPU which processes the information to determine if the vehicle is on an up grade, level or a down grade and also to determine the vehicle weight
  • Urge torque is normally defined to be a specific value of torque which is commanded from the engine to provide the driver with a feeling of the urge to move, that is to say the drive line slack has been taken up and the vehicle is ready for launch. It is normally a specific value of torque for a particular type of vehicle and has been determined empirically. A medium duty vehicle operating up to say about 26 tonnes, (approx 50,0001bs), an urge torque of about 61Nm (approx 45 ftlbs) has been determined to be a good value. Factors affecting the precise value of urge torque are those such as vehicle configuration, and whether it is preferred for the vehicle launch smoothly and with a minimum of delay or whether a slower response time is acceptable.
  • the CPU will calculate the value of modified urge torque, UT M0D , required to hold the vehicle in the particular circumstances. If the vehicle is on a level surface the urge torque will be equal to the normally stored and predetermined value. If the vehicle is facing uphill, then more torque will be needed to hold the vehicle in position without it rolling backwards.
  • the modified urge torque so that it is less than the urge torque.
  • the reduced value has a number of advantages, one of which is to reduce clutch slip and clutch wear. Also, if the vehicle is facing downhill, it is desirable to have the urge to move feeling, but with a reduced strength so that the vehicle is not accelerated down the hill, unless the driver wishes or commands such acceleration by pressing the throttle.
  • the modified urge torque is not always going to be greater than the predetermined urge torque, but in the downhill condition it could be less. Although its value may be low it cannot be negative, and will not be zero if the slack in the drive train is to be taken up.
  • the CPU of an automated transmission can normally calculate from input sensor information, such as transmission input shaft speed, output shaft speed, gear ratio and vehicle acceleration/deceleration the gradient of the road and the gross vehicle weight (GVW). Alternatively, such information may be available from an S AE Jl 939 data link or C AN-bus if it is fitted to the vehicle. Using the values of gradient and GVW, and with information about the torque characteristics of the engine it is possible to calculate the torque required to hold the vehicle in position on an uphill gradient.
  • input sensor information such as transmission input shaft speed, output shaft speed, gear ratio and vehicle acceleration/deceleration the gradient of the road and the gross vehicle weight (GVW).
  • GVW gross vehicle weight
  • the CPU also receives an input of gear ratio engaged which is used to determine if the transmission is in one of the start gears.
  • Sensed throttle position THL REP and the output shaft speed is also compared against a pre-determined reference value OS HEF . If the throttle setting is greater than the pre-determined reference value, and if output shaft speed is greater than the pre-determined reference value, then the CPU will determine the vehicle is not at rest or idle and so discontinue the routine and exit the process.
  • the process will continue. Providing the test conditions are satisfied the CPU can command that the engine speed be raised above idle speed to provide the modified urge torque. Once the engine is generating the modified urge torque the CPU commands the clutch controller 27 to start engaging the clutch to transmit the modified urge torque. The routine then ends.
  • This routine can be used to optimise the amount of clutch slip for all conditions.
  • the benefits of this system are a consistent feel to the "urge to move" independent of the load or grade.
  • By generating only the required amount of torque it is possible to keep the clutch slip to the minimum required whilst still presenting the driver with the "urge to move” feeling.
  • Minimising the amount of torque generated by the engine will minimise the amount of torque to be transmitted by the clutch and so reduce the amount of wear.
  • This has the advantage of reducing the amount of heat dissipated in the clutch. This enables the thermal capacity of the clutch to be used more efficiently.
  • An automated friction clutch (C) adapted to be fitted to a vehicle and engageable to transfer power from an engine (E) to a mechanical change gear transmission (11 ) and a central processing unit (CPU) for controlling operation of the clutch, and capable of sending command signals to the engine (E) and transmission, a plurality of sensors (22, 25, 28, 30) whose outputs are supplied as inputs to the central processing unit (CPU) for use in calculating the gradient on which the vehicle is operating and the weight of the vehicle (GVW), the calculated values of gradient and vehicle weight being used by the central processing unit (CPU) to calculate a value of modified urge torque (UT M0D ) and to provide command signals to the engine (E) to deliver to the clutch (C) a torque output equal to the modified urge torque (UT MO r > ) and to a clutch operator (27) to engage to said clutch (C) to the transmit the modified urge torque (UT MOD )-
  • modified urge torque is calculated to be equal to that required to maintain the vehicle in a stationary position on the level or an up gradient.
  • OS REF calculates a value for a modified urge torque (UT M0D ) and commands that the engine speed be raised above engine idle speed to provide modified urge torque (UT M0D ) and commands a clutch operator (27) to deliver the modified urge torque to the transmission (11).

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Automation & Control Theory (AREA)
  • Hydraulic Clutches, Magnetic Clutches, Fluid Clutches, And Fluid Joints (AREA)
  • Control Of Transmission Device (AREA)
  • Control Of Vehicle Engines Or Engines For Specific Uses (AREA)
  • Arrangement Of Transmissions (AREA)

Abstract

The invention relates to a method for calculating a modification to the predetermined amount of torque needed to provide an urge to move sensation for a vehicle, the modification to take account of the weight at which and gradient on which the vehicle is operating and then commanding the engine to generate said modified torque and to transmit the modified urge torque to a clutch device to provide the urge to move according to the current operating conditions.

Description

CALCULATION OF AUTOMATED FRICTION CLUTCH URGE TORQUE ON GRADES
This invention relates to improvements in vehicle transmissions, in particular to vehicles fitted with automated transmissions and clutch systems.
When driving a vehicle fitted with a change gear ratio transmission connected to an engine by a torque converter the operation of the transmission is characterised by the slip and torque multiplication available from the torque converter section. The "feel" of the transmission is recognisable by an "urge to move" when the vehicle is stationary. This urge to move is caused by the stall torque of the torque converter at engine idle speed. On an uphill incline it can prevent the vehicle moving backward when the vehicle is stationary and the driver moves his foot from the brake to the accelerator pedal.
An Automated Mechanical Transmission (AMT) includes a change gear transmission and normally also includes a Central Processing Unit (CPU) which controls the selection of gear and the operation of the gear selector mechanism. Normally, an AMT is coupled to a conventional friction clutch, rather than a known hydraulic torque converter. In more advanced versions of the AMT, the clutch control is also automated and the driver has only two pedals in the cab, a throttle control or accelerator pedal and a brake pedal. Normal or manually operated clutches control the clutch and do not present the driver with an "urge to move" feeling. When stationary, the clutch is normally completely disengaged in order to minimise the clutch wear and avoid excessive heat dissipation that would arise from a continually slipping clutch. In these conditions there is nothing to prevent a vehicle fitted with an AMT rolling forwards or backwards if the driver has not applied either the parking brake or service brake using the pedal.
In a commercial vehicle having 6, 9 or even more forward speed ratios there is the possibility of selecting a gear other than first gear for engagement. Commonly in such vehicles with a 6 speed transmission the starting gear will be 2nd or 3 rd. For heavier vehicles with 12 or 16 speed transmissions the starting gear will be 3r or 5lh and occasionally 7lh if the vehicle is unladen and setting off in a downhill direction. With the choice of a number of start ratios it is possible to select a ratio which can minimise the clutch slip and heat generation during the launch phase.
It is desirable to present the driver with an indication the vehicle is ready for launch and can move off quickly when commanded to do so. In this specification the expression "urge to move" is intended to mean that a vehicle is ready to move and the drive line slack has been taken up and there is a sensation given to the driver that the vehicle will move off if the brakes are released. It does not necessarily mean that the vehicle will creep forward (or backwards), as would tend to be the case, for a vehicle fitted with a conventional torque converter, but it is intended to indicate that sufficient torque is being transmitted through the vehicle drive-line to take up any slack in the drive-line components and that the vehicle will not just roll in a downhill direction if it is at rest on a gradient without a brake applied. The Urge Torque is the amount of torque required to give the urge to move feeling and make the vehicle feel as if it is ready to move off from rest. It is an empirically determined figure that will depend on the weight and type of vehicle. It can be qualitatively described as the amount of torque needed to provide the driver with the sensation that at least any slack in the drive-line has been partially taken up and the clutch engagement process has started and so the vehicle is ready to move off.
Allowing the partial engagement of the clutch to provide slip under zero speed conditions partially replicates the sensations of a torque converter type system and provides the urge to move feeling experienced with such systems. An automated clutch system can be programmed to transmit a greater amount of torque and so provide a limited amount of movement' and so replicate the "creep" function. Alternatively, when a vehicle is on an uphill gradient it is desirable to provide a hill holding capability in which the vehicle can be held stationary by the engine running at or slightly above idle speed and slipping clutch without the need for application of an additional braking force. It is also clear that when a vehicle is laden the amount of torque required to prevent the vehicle rolling backwards is greater than that required when it is unladen or on a flat or level surface. Clearly, it is desirable to ensure enough torque is available to provide the urge to move in the particular circumstances which the vehicle minimise the amount of slip and therefore heat generated in order to maximise clutch life. According to the present invention there is provided an automated friction clutch, adapted to be fitted to a vehicle and engageable to transfer power from an engine to a mechanical change gear transmission and a central processing unit for controlling operation of the clutch, and capable of sending command signals to the engine and transmission, a plurality of sensors, whose outputs are supplied as inputs to the central processing unit (CPU) for use in calculating the gradient on which the vehicle is operating and the weight of the vehicle, the calculated values of gradient and vehicle weight being used by the central processing unit to calculate a value of modified urge torque and to provide command signals to the engine to deliver to the clutch a torque output equal to the modified urge torque and to a clutch operator to engage to said clutch to the transmit the modified urge torque.
The invention will now be described with reference to the accompanying drawings in which: Figure 1 shows a general schematic view of a transmission system, and
Figure 2 shows a flow chart for the operation of a logic sequence for operation of a transmission in the mode described.
Figure 1 shows a transmission system 10 includes an engine E having an output shaft 12 connected to a clutch C, which is in turn connectable to an input shaft 16 of a change gear transmission 11. The transmission 11 is has an output shaft 20 connected to the drive wheels (not shown) of the vehicle.
The transmission system is controlled by a central processing unit (CPU) 30, which preferably is a single processing unit, but alternatively could be a plurality of processing units distributed processing units. In such circumstances the processing units may be located on the transmission, in the vehicle cab, on the engine, on the chassis or any combination of these. The transmission will normally have a number of modes in which it can operate, including manual and automatic. There may be additional functions to enable the shift points to be adjusted to suit the prevailing conditions.
The engine power demanded by a driver is signaled by TFf 22, whose output signal is sent to the CPU 30. The CPU 30 then communicates the demanded power as an output signal to the engine E along link 23. The driver will also be provided with a gear ratio selector lever 34, usable to select a transmission ratio or to override the selection made by the CPU if the transmission is in automatic mode. Operation of the clutch is controlled by the CPU whose control signals are sent to a clutch operator 27. Operation of the transmission will be by known means not forming a part of this invention. The gear ratio selector lever 34 operates a set of contacts in unit 36 to provide an output signal to the CPU 30. The selector lever 34 is used by the driver to select a gear ratio or to override the ratio selected by the transmission CPU. Further inputs to the CPU are from sensors ES, IS and OS which measure engine speed, transmission input shaft speed and transmission output shaft speed respectively. Output shaft speed can be used to determine vehicle speed in known manner. The transmission controller 29 will also supply information about the currently engaged gearratio (GR). From this information, it is possible to calculate GNW in known manner. Another source of GVW information could be the SAE J1939 data-link or "CAN bus" system if one of these is fitted to the vehicle.
Figure 2 shows a flow chart sequence for implementation of the present invention. Values of throttle position THL, output shaft speed OS, engine speed ES and input shaft speed IS are taken from the sensors 22, 25, 28, and 30 and supplied to .the CPU which processes the information to determine if the vehicle is on an up grade, level or a down grade and also to determine the vehicle weight
The information on grade and weight is then used to calculate the amount of torque (modified urge torque) needed to maintain the vehicle in a steady state in the particular circumstances. Urge torque is normally defined to be a specific value of torque which is commanded from the engine to provide the driver with a feeling of the urge to move, that is to say the drive line slack has been taken up and the vehicle is ready for launch. It is normally a specific value of torque for a particular type of vehicle and has been determined empirically. A medium duty vehicle operating up to say about 26 tonnes, (approx 50,0001bs), an urge torque of about 61Nm (approx 45 ftlbs) has been determined to be a good value. Factors affecting the precise value of urge torque are those such as vehicle configuration, and whether it is preferred for the vehicle launch smoothly and with a minimum of delay or whether a slower response time is acceptable.
The CPU will calculate the value of modified urge torque, UTM0D, required to hold the vehicle in the particular circumstances. If the vehicle is on a level surface the urge torque will be equal to the normally stored and predetermined value. If the vehicle is facing uphill, then more torque will be needed to hold the vehicle in position without it rolling backwards.
Whilst the normal urge to move torque will slow the rate at which the vehicle rolls backwards compared to a similar set of circumstances when the vehicle is on the level, it is desirable, if possible, to provide in addition, a hill holding capability. In providing a full hill holding capability a number of important criteria need to be considered, primarily the thermal performance of the clutch and its ability to dissipate the heat generated during the hill holding process. Clearly, a small capacity clutch will have a lower thermal capacity (and torque transmitting capacity) than a comparable larger unit, and for similar sized clutches, wet clutches fitted with coolers have more capacity than ordinary wet clutches, which in turn have more capacity than dry clutches. In determining whether a system can have a full hill holding capacity these factors have to be considered. It will be important also to incorporate thermal warning and thermal protection systems, the design and details of which fall outside the scope of this invention.
If the vehicle is on a downhill gradient, then it will be desirable to reduce the modified urge torque so that it is less than the urge torque. The reduced value has a number of advantages, one of which is to reduce clutch slip and clutch wear. Also, if the vehicle is facing downhill, it is desirable to have the urge to move feeling, but with a reduced strength so that the vehicle is not accelerated down the hill, unless the driver wishes or commands such acceleration by pressing the throttle.
It can thus be seen that the modified urge torque is not always going to be greater than the predetermined urge torque, but in the downhill condition it could be less. Although its value may be low it cannot be negative, and will not be zero if the slack in the drive train is to be taken up.
In order for the engine to generate the required torque it is necessary to raise the engine speed above idle level, primarily to ensure the control of the engine rests with the transmission CPU rather than the engine CPU. An increase above engine idle speed of between 50 and 100 rpm is needed depending upon the engine, but normally about 50rpm is sufficient to achieve the desired effect. The CPU of an automated transmission can normally calculate from input sensor information, such as transmission input shaft speed, output shaft speed, gear ratio and vehicle acceleration/deceleration the gradient of the road and the gross vehicle weight (GVW). Alternatively, such information may be available from an S AE Jl 939 data link or C AN-bus if it is fitted to the vehicle. Using the values of gradient and GVW, and with information about the torque characteristics of the engine it is possible to calculate the torque required to hold the vehicle in position on an uphill gradient.
The CPU also receives an input of gear ratio engaged which is used to determine if the transmission is in one of the start gears. Sensed throttle position (THL) provides an input 22 which is compared against a pre-determined reference value THLREP and the output shaft speed is also compared against a pre-determined reference value OSHEF. If the throttle setting is greater than the pre-determined reference value, and if output shaft speed is greater than the pre-determined reference value, then the CPU will determine the vehicle is not at rest or idle and so discontinue the routine and exit the process.
If the throttle setting is less than the pre-determined reference value, and if output shaft speed is less than a pre-determined reference value and the vehicle is in one of the permitted start gear ratios, then the process will continue. Providing the test conditions are satisfied the CPU can command that the engine speed be raised above idle speed to provide the modified urge torque. Once the engine is generating the modified urge torque the CPU commands the clutch controller 27 to start engaging the clutch to transmit the modified urge torque. The routine then ends.
This routine can be used to optimise the amount of clutch slip for all conditions. The benefits of this system are a consistent feel to the "urge to move" independent of the load or grade. By generating only the required amount of torque it is possible to keep the clutch slip to the minimum required whilst still presenting the driver with the "urge to move" feeling. Minimising the amount of torque generated by the engine will minimise the amount of torque to be transmitted by the clutch and so reduce the amount of wear. This has the advantage of reducing the amount of heat dissipated in the clutch. This enables the thermal capacity of the clutch to be used more efficiently. In the case when the vehicle is on the level or an up incline, this could mean a longer period of clutch slip, and in the hill holding mode a capability to hold the vehicle on a steeper gradient These benefits can be used to maximise the clutch life or improve the capability of the system under these difficult conditions. CLAIMS:
1. An automated friction clutch (C), adapted to be fitted to a vehicle and engageable to transfer power from an engine (E) to a mechanical change gear transmission (11 ) and a central processing unit (CPU) for controlling operation of the clutch, and capable of sending command signals to the engine (E) and transmission, a plurality of sensors (22, 25, 28, 30) whose outputs are supplied as inputs to the central processing unit (CPU) for use in calculating the gradient on which the vehicle is operating and the weight of the vehicle (GVW), the calculated values of gradient and vehicle weight being used by the central processing unit (CPU) to calculate a value of modified urge torque (UTM0D ) and to provide command signals to the engine (E) to deliver to the clutch (C) a torque output equal to the modified urge torque (UTMOr> ) and to a clutch operator (27) to engage to said clutch (C) to the transmit the modified urge torque (UTMOD)-
2. A system according to claim 1 in which the modified urge torque is calculated to be equal to that required to maintain the vehicle in a stationary position on the level or an up gradient.
3. A system according to claim 1 in which the modified urge torque is equal to or more than the urge torque if the vehicle is on the level or an up gradient
4. A system according to claim 1 in which the modified urge torque is less than the urge torque if the vehicle is on a down gradient.
5. A method of controlling an automated friction clutch system coupled between an engine (E) controlled by a throttle and a mechanical change gear transmission (11), said clutch system connected to a central processing unit (CPU), and in which the CPU: i) receives an input of transmission gear ratio engaged (GR), ii) determines if the gear ratio engaged is one of the start gears, iii) receives a sensed throttle position (THL) input (22) from a throttle position sensor which senses throttle position of said engine E, iv) compares sensed throttle position (THL) against a pre-determined reference value (THLREF) and v) compares transmission output shaft speed (OS) against a pre-determined reference value
(OSREF), and if the transmission is in one of the allowed start gear ratios, and if the throttle setting (THL) is less than the pre-determined reference valueCTHLREF ), and if output shaft speed (OS) is less than a pre-determined reference value
(OSREF), then calculates a value for a modified urge torque (UTM0D ) and commands that the engine speed be raised above engine idle speed to provide modified urge torque (UTM0D ) and commands a clutch operator (27) to deliver the modified urge torque to the transmission (11).
6. A method according to claim 5 in which the modified urge torque is calculated to be equal to that required to maintain the vehicle in a stationary position on the level or an up gradient.
7. A method according to claim 5 in which the modified urge torque is equal to or more than the urge torque if the vehicle is on the level or an up gradient
8. A method according to claim 5 in which the modified urge torque is less than the urge torque if the vehicle is on a down gradient.
PCT/IB2001/001323 2000-07-26 2001-07-24 Calculation of automated friction clutch urge torque on grades WO2002008011A1 (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
JP2002513723A JP2004504217A (en) 2000-07-26 2001-07-24 Calculating slip on graded roads
DE60125370T DE60125370T2 (en) 2000-07-26 2001-07-24 CALCULATION OF THE HOLDING MOMENT OF AN AUTOMATED COUPLING ON CASES
BRPI0113014-5A BR0113014B1 (en) 2000-07-26 2001-07-24 system and method for controlling automated friction clutch.
AU2002224540A AU2002224540A1 (en) 2000-07-26 2001-07-24 Calculation of automated friction clutch urge torque on grades
US10/333,163 US7041031B2 (en) 2000-07-26 2001-07-24 Calculation of automated friction clutch urge torque on grades
EP01984323A EP1303422B1 (en) 2000-07-26 2001-07-24 Calculation of automated friction clutch urge torque on grades

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB0018186.7 2000-07-26
GBGB0018186.7A GB0018186D0 (en) 2000-07-26 2000-07-26 Calculation of slip on grades

Publications (1)

Publication Number Publication Date
WO2002008011A1 true WO2002008011A1 (en) 2002-01-31

Family

ID=9896277

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2001/001323 WO2002008011A1 (en) 2000-07-26 2001-07-24 Calculation of automated friction clutch urge torque on grades

Country Status (9)

Country Link
US (1) US7041031B2 (en)
EP (1) EP1303422B1 (en)
JP (1) JP2004504217A (en)
CN (1) CN100419308C (en)
AU (1) AU2002224540A1 (en)
BR (1) BR0113014B1 (en)
DE (1) DE60125370T2 (en)
GB (1) GB0018186D0 (en)
WO (1) WO2002008011A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004009396A1 (en) * 2002-07-18 2004-01-29 Hoerbiger Antriebstechnik Gmbh Load-transporting vehicle, particularly forklift
WO2004082977A1 (en) * 2003-03-15 2004-09-30 Daimlerchrysler Ag Method for operating a hill-holder device in a motor vehicle
US8090499B2 (en) 2004-11-23 2012-01-03 GM Global Technology Operations LLC Anti-rollback control via grade information for hybrid and conventional vehicles

Families Citing this family (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7617035B2 (en) * 2002-05-27 2009-11-10 Luk Lamellen Und Kupplungsbau Beteiligungs Kg Method for operating a drive train by treating the motor characteristic by means of parallel evaluation and PT1-filtering
SE524510C2 (en) * 2002-12-30 2004-08-17 Volvo Lastvagnar Ab Method and device for starting uphill
DE102005001550A1 (en) * 2005-01-13 2006-07-27 Zf Friedrichshafen Ag Method for starting control of a motor vehicle
US7630811B2 (en) * 2005-01-18 2009-12-08 Ford Global Technologies, Llc Automated manual transmission launch control
US7166060B2 (en) * 2005-01-18 2007-01-23 Ford Global Technologies, Llc. Hill hold for a vehicle
US20070191181A1 (en) * 2006-02-13 2007-08-16 Burns Robert D Method and apparatus for controlling vehicle rollback
US7853388B2 (en) 2006-02-23 2010-12-14 Siemens Industry, Inc. Devices, systems, and methods for controlling a braking system
KR100774646B1 (en) * 2006-04-07 2007-11-08 현대자동차주식회사 Shift control method of Automatic Transmission
DE102006037704A1 (en) * 2006-08-11 2008-02-14 Zf Friedrichshafen Ag Method for driving resistance-dependent adjustment of the clutch torque of a motor vehicle
FR2915158B1 (en) * 2007-04-19 2009-10-02 Renault Sas METHOD FOR ASSISTING AT THE SIDE MANEUVER FOR A VEHICLE
DE102007055085B4 (en) * 2007-11-16 2019-02-21 Getrag-Ford Transmissions Gmbh Method for preventing uncontrolled rollback
US8041489B2 (en) * 2008-05-12 2011-10-18 GM Global Technology Operations LLC Method for controlling a transmission during acceleration from idle
EP2135785B1 (en) * 2008-05-26 2011-10-12 C.R.F. Società Consortile per Azioni Control system for a motor vehicle provided with a semiautomatic gearbox with discrete ratios
JP5273121B2 (en) * 2010-10-19 2013-08-28 株式会社デンソー Start support device
JP5549660B2 (en) * 2011-11-10 2014-07-16 トヨタ自動車株式会社 Vehicle control device
US9278692B2 (en) * 2012-05-04 2016-03-08 Ford Global Technologies, Llc Methods and systems for a four wheel drive vehicle driveline
US9783181B2 (en) * 2012-11-20 2017-10-10 Eaton Corporation Method and apparatus of propelling a vehicle
WO2015019766A1 (en) * 2013-08-05 2015-02-12 日産自動車株式会社 Vehicle control device and vehicle control method
US9539998B2 (en) 2015-04-08 2017-01-10 Toyota Motor Engineering & Manufacturing North America, Inc. System and method for improved control, response and energy management of a vehicle
CN106184208B (en) * 2015-05-07 2018-09-11 比亚迪股份有限公司 The control method and system of automobile up slope traveling
US10316959B2 (en) 2016-01-29 2019-06-11 Cnh Industrial America Llc System and method for controlling a work vehicle transmission based on the detection of unintended vehicle motion
EP3438491B1 (en) * 2016-03-29 2020-04-08 Honda Motor Co., Ltd. Driving force control device for straddle-type vehicles
WO2017175310A1 (en) * 2016-04-05 2017-10-12 日産自動車株式会社 Start clutch control method and start clutch control device
US11112004B2 (en) 2019-10-01 2021-09-07 Allison Transmission, Inc. Transmission control systems to adjust clutch pressure and torque based on grade
CN111456861B (en) * 2020-06-22 2020-12-22 盛瑞传动股份有限公司 Engine torque control method suitable for clutch slipping fault
CN112810613B (en) * 2021-01-07 2023-06-20 东风柳州汽车有限公司 Starting energy consumption optimization method, starting energy consumption optimization device, starting energy consumption optimization equipment and storage medium
CN114263734B (en) * 2021-12-29 2023-05-23 潍柴动力股份有限公司 Control method and device for output torque of vehicle engine

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4662491A (en) * 1984-05-04 1987-05-05 Diesel Kiki Co., Ltd. Apparatus for controlling a clutch for vehicles
DE19841917A1 (en) * 1998-09-14 1999-12-16 Mannesmann Sachs Ag Drive system for motor vehicles
DE19838972A1 (en) * 1998-08-27 2000-03-23 Bayerische Motoren Werke Ag Stopping vehicle having controllable torque transmission unit and engine torque regulation on hill in number of steps and determining stopping operation on hill by evaluating determined travel operating conditions

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62198530A (en) * 1986-02-27 1987-09-02 Aisin Seiki Co Ltd Automatic clutch controller
JP2748470B2 (en) * 1988-12-20 1998-05-06 いすゞ自動車株式会社 Automatic transmission for vehicles
DE4223084A1 (en) * 1992-07-14 1992-11-26 Zahnradfabrik Friedrichshafen METHOD FOR ELECTRONICALLY CONTROLLING AN AUTOMATIC MANUAL TRANSMISSION
KR960001444A (en) * 1994-06-06 1996-01-25 가나이 쯔도무 Power Train Control System and Control Method
GB9504681D0 (en) * 1995-03-08 1995-04-26 Eaton Corp Improvements in vehicle control
US6071211A (en) * 1998-11-18 2000-06-06 Eaton Corporation Idle drive torque control for automated vehicle master clutch
US6636795B1 (en) * 1999-05-17 2003-10-21 Eaton Corporation Powertrain torque control
JP3546401B2 (en) * 1999-08-06 2004-07-28 本田技研工業株式会社 Vehicle driving force control device
GB2361980A (en) * 2000-05-05 2001-11-07 Eaton Corp Dry clutch control system using idle drive torque so as to provide vehicle crawl speed

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4662491A (en) * 1984-05-04 1987-05-05 Diesel Kiki Co., Ltd. Apparatus for controlling a clutch for vehicles
DE19838972A1 (en) * 1998-08-27 2000-03-23 Bayerische Motoren Werke Ag Stopping vehicle having controllable torque transmission unit and engine torque regulation on hill in number of steps and determining stopping operation on hill by evaluating determined travel operating conditions
DE19841917A1 (en) * 1998-09-14 1999-12-16 Mannesmann Sachs Ag Drive system for motor vehicles

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004009396A1 (en) * 2002-07-18 2004-01-29 Hoerbiger Antriebstechnik Gmbh Load-transporting vehicle, particularly forklift
WO2004082977A1 (en) * 2003-03-15 2004-09-30 Daimlerchrysler Ag Method for operating a hill-holder device in a motor vehicle
US8090499B2 (en) 2004-11-23 2012-01-03 GM Global Technology Operations LLC Anti-rollback control via grade information for hybrid and conventional vehicles
DE102005055592B4 (en) * 2004-11-23 2015-11-26 General Motors Corp. Control for hybrid and conventional vehicles to prevent rollback using slope information

Also Published As

Publication number Publication date
CN100419308C (en) 2008-09-17
EP1303422A1 (en) 2003-04-23
US7041031B2 (en) 2006-05-09
DE60125370D1 (en) 2007-02-01
AU2002224540A1 (en) 2002-02-05
BR0113014B1 (en) 2013-02-05
DE60125370T2 (en) 2007-09-27
CN1443123A (en) 2003-09-17
JP2004504217A (en) 2004-02-12
BR0113014A (en) 2004-01-06
EP1303422B1 (en) 2006-12-20
GB0018186D0 (en) 2000-09-13
US20040033861A1 (en) 2004-02-19

Similar Documents

Publication Publication Date Title
EP1303422B1 (en) Calculation of automated friction clutch urge torque on grades
US7226389B2 (en) Method and device for hill start
US6676561B2 (en) Torque transfer system for a motor vehicle
US7833127B2 (en) Method for adjusting the clutch torque of a motor vehicle depending upon the driving resistance
EP1303713B1 (en) Automatic selection of start gear
US8401750B2 (en) Method and device for automatic or semiautomatic selection of a better starting gear in a vehicle
JP5162916B2 (en) Hybrid regenerative braking control device for hybrid vehicle
KR100764319B1 (en) Temperature-dependent control device of a coupling or an automobile transmission
JP2002168333A (en) Hill-hold control device of automobile
KR19990028319A (en) Apparatus for controlling a torque delivery system
US9043102B2 (en) Brake assist function
JPH1071875A (en) Automobile and method to be applied to this automobile
SE1251463A1 (en) Procedure and system for controlling a clutch in a vehicle
JP5185954B2 (en) How to operate an automatic or semi-automatic transmission of a large vehicle in idling mode
EP1929187B1 (en) A method for operating an automatic or semi-automatic manual transmission of a heavy vehicle when in idle-driving mode
SE525365C2 (en) Motor-driven vehicle with auxiliary brakes and a method for controlled speed change during a shift course with such a vehicle
KR200431446Y1 (en) The Automobile electronic connect-disconnect gear system following driving status
US20040058778A1 (en) Low speed manoeuvring control
WO1996010492A2 (en) Improvements in transmission systems for vehicles
SE1151280A1 (en) Procedure and system for controlling a clutch in a vehicle

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
WWE Wipo information: entry into national phase

Ref document number: 2001984323

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 018130429

Country of ref document: CN

WWP Wipo information: published in national office

Ref document number: 2001984323

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

WWE Wipo information: entry into national phase

Ref document number: 10333163

Country of ref document: US

WWG Wipo information: grant in national office

Ref document number: 2001984323

Country of ref document: EP