Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
  • B60K31/00—Vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed, i.e. preventing speed from exceeding an arbitrarily established velocity or maintaining speed at a particular velocity, as selected by the vehicle operator
  • B60K31/02—Vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed, i.e. preventing speed from exceeding an arbitrarily established velocity or maintaining speed at a particular velocity, as selected by the vehicle operator including electrically actuated servomechanism including an electric control system or a servomechanism in which the vehicle velocity affecting element is actuated electrically
  • B60K31/04—Vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed, i.e. preventing speed from exceeding an arbitrarily established velocity or maintaining speed at a particular velocity, as selected by the vehicle operator including electrically actuated servomechanism including an electric control system or a servomechanism in which the vehicle velocity affecting element is actuated electrically and means for comparing one electrical quantity, e.g. voltage, pulse, waveform, flux, or the like, with another quantity of a like kind, which comparison means is involved in the development of an electrical signal which is fed into the controlling means
  • B60K31/042—Vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed, i.e. preventing speed from exceeding an arbitrarily established velocity or maintaining speed at a particular velocity, as selected by the vehicle operator including electrically actuated servomechanism including an electric control system or a servomechanism in which the vehicle velocity affecting element is actuated electrically and means for comparing one electrical quantity, e.g. voltage, pulse, waveform, flux, or the like, with another quantity of a like kind, which comparison means is involved in the development of an electrical signal which is fed into the controlling means where at least one electrical quantity is set by the vehicle operator
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T10/00—Control or regulation for continuous braking making use of fluid or powdered medium, e.g. for use when descending a long slope
  • B60T10/02—Control or regulation for continuous braking making use of fluid or powdered medium, e.g. for use when descending a long slope with hydrodynamic brake
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT 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
  • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
  • B60W10/04—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units
  • B60W10/06—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units including control of combustion engines
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT 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
  • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
  • B60W10/18—Conjoint control of vehicle sub-units of different type or different function including control of braking systems
  • B60W10/196—Conjoint control of vehicle sub-units of different type or different function including control of braking systems acting within the driveline, e.g. retarders
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT 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
  • B60W30/00—Purposes 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
  • B60W30/18—Propelling the vehicle
  • B60W30/18009—Propelling the vehicle related to particular drive situations
  • B60W30/18109—Braking
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT 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
  • B60W50/00—Details 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
  • B60W50/02—Ensuring safety in case of control system failures, e.g. by diagnosing, circumventing or fixing failures
  • B60W50/0205—Diagnosing or detecting failures; Failure detection models
  • B60W2050/021—Means for detecting failure or malfunction
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT 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
  • B60W2710/00—Output or target parameters relating to a particular sub-units
  • B60W2710/06—Combustion engines, Gas turbines
  • B60W2710/0605—Throttle position

Definitions

• Engine 1 is controlled under the influence of an engine control unit 6 and retarder 5 is controlled under the influence of a retarder control unit 7.
• Both these control units 6, 7 are suitably of the electrical type which are arranged to regulate engine throttle and the braking effect of the retarder system, respectively, depending on input signals representing different engine parameters, vehicle parameters, and controls actuated manually by the driver.
• Both control units each incorporate a microprocessor (CPU 61, 71 and a memory 62, 72 for execution of the processes described later on in the description.
• Engine control unit 6 is therefore connected, among other things, to a sensor 8 on engine 1 for sensing the engine speed, and a sensor in fuel injection system 9 of the engine, to allow direct sensing of the engine driving moments transmitted.
• engine control unit 6 is connected to external sensors, of which only a vehicle speed sensor 10, an accelerator pedal sensor 11 and a control 12 actuated manually by the driver, for a cruise control function, are shown in the figure.
• Engine control unit 6 is also connected to different engine control mechanisms, such as fuel injection system 9, for regulating the same for controlling engine 1, and for sensing the injecgted fuel flow rate, i.e. the engine driving moment transmitted.
• the cruise control function of engine control unit 6 is therefore intended to cause engine control unit 6 to regulate engine 1 to a speed equivalent to the vehicle speed required by the driver, depending on the setting 6 selected by the driver by means of control 12.
• the required vehicle speed is stored as a setpoint V esecp .
• control 12 may be designed so that when control 12 has been actuated it stores the speed reached thereby as a setpoint V esetp .
• the control is achieved principally by regulating fuel injection system 9 of the engine.
• Engine control systems of this type are already on the market in the form of SCANIA's EDC system, (Electronic Diesel Control) .
• Retarder control unit 7 is correspondingly connected to control mechanism 15 for activating a cruise control function of retarder 5.
• retarder control unit 7 is able to store a speed setpoint V rsetp . in memory 72 of retarder control unit 7.
• This setpoint V rsetp . can be conventionally and automatically set to the instantaneous vehicle speed when the driver activates the cruise control function of retarder control unit 7 by means of control 15 designed for this purpose.
• the driver may be provided with programmable controls for determining different speed setpoints which can be selectively chosen by the driver.
• the different speed setpoints consist of speed setpoints B msetp . and V rsetp ., respectively, individually intended for each control system.
• Retarder control unit 7 is suitably constructed by the method described in greater detail in SE 460781 mentioned in the preamble.
• the respective control units 7, 6 of retarder 5 and engine 1 are also connected to each other, and information on different parameters is transmitted directly between them.
• the fact that control units 6, 7 communicate with each other in this way is denoted in
• Retarder control unit 7 therefore receives information via engine control unit 6 on the engine torque, accelerator position 4
• FIG 1 shows a drive system with a transmission for a vehicle.
• This relates mainly to a heavier vehicle such as a truck or bus, engine 1 being preferably a diesel engine.
• the drive system therefore incorporates, conventionally, an engine 1 and a gearbox 2 connected to it by driving power.
• the driving power is transmitted from gearbox 2 to the driving wheels 3 of the vehicle via a cardan shaft 4.
• a retarder 5 which, when activated, can be used as an auxiliary brake, is connected to gearbox 2.
• retarder 5 is of the hydraulic type, but alternatively it may be of an electrical type, e.g. an eddy current brake, or another known type.
• the braking moment influencing the vehicle will be described as a braking moment obtained from retarder 5.
• the braking effect from retarder 5 can be suitably regulated in different effect stages, depending on the braking effect required.
• other additional brakes can be activated, such as an exhaust brake (not shown) .
• an exhaust brake may be suitably coordinated with a retarder function so that when the retarder function initiates active control the exhaust brake, as the first primary braking effect stage, can come into operation before the braking effect stage of the preferably hydrodynamic retarder is eventually engaged.
• the exhaust brake can be actuated secondarily after all the braking effect stages in the hydrodynamic retarder have been activated and when increased braking effect is still sought.
• additional brakes are meant brakes supplementary to the ordinary friction brakes of the vehicle for the wheels, which should be saved wherever possible to avoid overheating, with the 3
• the process and arrangement according to the invention enables both systems for cruise control to be activated simultaneously when driving downhill without any risk that the systems will counteract each other.
• the engine control system automatically takes over the cruise control function without the driver having to reactivate any of the controls. This applies provided that the cruise control function of the retarder is engaged when the engine acceleration is low.
• the cruise control function of the engine control system is disengaged to prevent the systems from counteracting each other.
• Figure 1 is an explanatory diagram showing the construction of an arrangement for cruise control according to the invention
• Figure 2 shows a flow chart of how a process for cruise control takes place
• Figure 3 shows a flow chart according to Figure 2, with an alternative condition. 2 speed will increase to a value exceeding the speed setpoint determined by the cruise control when the vehicle encounters a descent of sufficient gradient on which the engine braking function is insufficient to maintain the speed.
• the cruise control function is automatically disengaged by means of the engine control system when the cruise control function is activated by means of the retarder control system. Otherwise there is a risk that the engine control system may adjust the engine to full throttle whilst the retarder system simultaneously adjusts the retarder to maximum braking.
• the objective of this invention is to provide a system for controlling the cruise control functions of a vehicle making optimum use of the engine control system and the retarder control system.
• One objective is therefore to ensure that there is no risk of the systems counteracting each other.
• a further objective is to reduce the need for renewed driver activation of the cruise control function.
• the invention must be simple and cheap to produce and use, and it must also be possible for existing vehicles equipped with arrangements for cruise control to be modified, according to the conditions described, so that the invention can be utilised.
• One further objective is to guarantee a simple, user- friendly control system which provides safe, economical propulsion of the engine vehicle.
• This invention relates to a process and an arrangement for vehicle cruise control in accordance with the statements made in the preamble to patent claim 1 and patent claim 6 respectively.
• the cruise control function must be reactivated on every descent where the driver wants the cruise control function to be activated.
• For the retarder control systems of modern vehicles are designed so that it is not possible to drive the vehicle with the retarder engaged whilst the driver has his foot on the accelerator in addition to the idle throttle. When the vehicle reaches a flat section of road or an uphill section after the descent the driver must accelerate, thereby automatically disengaging the cruise control function.
• Modern vehicles also have control systems for engine regulation which normally also include a function for keeping the speed of the vehicle constant by means of engine control.
• This cruise control function is therefore designed mainly for driving on flat roads and uphill, where the driving resistance of the vehicle is so great that the accelerator must be pressed to maintain the speed of the vehicle.
• This type of cruise control is therefore based on the fact that the engine is adjusted by a suitable throttle to maintain a constant vehicle speed. With only this type of regulation the vehicle and other parameters.
• Both control units are also connected to each other so that they can exchange information on whether each other's cruise control functions are activated or not, so that they can influence each other according to the detailed description given below.
• the designation CC is used for the respective cruise control functions and derives from the English term cruise- control.
• Figure 2 shows, in the form of a flow chart, how both control units 6, 7 interact with each other under different driving conditions, and above all how their respective cruise control functions interact.
• the process described in Figure 2 presupposes that at least one of control systems 6, 7, but normally both, is (are) based on microcomputer technology.
• both systems 6, 7 are of the microcomputer type and the program which controls the process is stored in memory 72 in retarder control unit 7, and is processed in its microprocessor 71.
• the program is designed as a sub-program to a main program stored in control unit 7, which normally controls the retarder.
• Control 15 can either be designed with a button or the like which can be activated by the driver, or can be designed as a control mechanism with step-by- step adjustment for obtaining different braking moments, as described in SE 460781.
• control 15 therefore constitutes a first starting stage 20, and gives rise in a second stage 22 to activation of the cruise control function of retarder 5.
• control unit 7 of retarder 5 will regulate the braking function of the retarder so that the vehicle does not exceed the adjustedt speed setpoint V rsetp _
• the function is activated by the driver mainly when driving downhill.
• a third stage 23 it is sensed whether the cruise control function of engine control unit 6 is activated or not. If it is not, the program returns directly to a main program in a final stage 26, and the control process continues according to the conditions stored in it.
• the cruise control function of engine control unit 6 is activated, the engine torque is sensed in a fourth stage 24.
• the predetermined torque value has been selected in this embodiment at 5% of the maximum torque of engine 1, and corresponds essentially to the torque generated by the engine during or close to idling. In other engines this idling torque may be equal to a higher or lower percentage of the maximum engine torque. If, however, the engine torque is equal to or exceeds the predetermined value, the cruise control function of engine 1 is disengaged in a fifth stage 25. On the other hand, the cruise control function of retarder 5 remains activated. In the final stage 26 the program then returns to the main program, but in this case with only the cruise control system of the retarder activated. It is therefore the comparison made in the fourth stage 24 which determines whether the cruise control function of engine control unit 6 is to remain activated or not on return to the main program.
• the cruise control function of retarder control unit 7 In order to give the driver better control over the vehicle it is instead desirable for the cruise control function of retarder control unit 7 always to be disengaged during throttle, either manually by means of the accelerator, disengaged with the clutch pedal of the vehicle, or automatically as soon as the cruise control function of engine control unit 6 is engaged with active torque throttle. Otherwise, if a latent braking effect begins at any time as soon as the speed exceeds a certain value, there is a risk that the vehicle may skid where the road surface is poor, and particularly when it is slippery. This is disastrous for heavy truck trains which sometimes have trailers, and where skidding may be very difficult to stop.
• the design of the invention can be modified so that it is able to control on the basis of other engine or vehicle parameters sensed directly or indirectly.
• Figure 3 shows a flow chart of a process according to a modified design. What distinguishes this from the design shown and described with reference to Figure 2 is the criterion used in a comparison to indicate whether the cruise control function of engine control unit 6 is to be automatically disengaged or not.
• the initial stages 20-23 are therefore the same as before, which is why the same reference designations are used in the figure from the start up to and including the third stage.
• the fourth stage 24 ' there is no selection based on the engine torque. Instead the speed V of the vehicle is used as a parameter for the comparison and continued selection.
• the speed V of the vehicle is representative of the speed setpoint V rsetp . to which retarder 5 is adjusted. If speed V of the vehicle exceeds setpoint V eseCp . to which the cruise control function of engine control unit 6 is set, this means that retarder 5, which is now regulating, uses a speed setpoint V rsetp .. which is higher than speed setpoint V es ⁇ tp . of engine control unit 6. In such a situation there is no risk that the engine control system would begin to regulate at the same time as the retarder control system. It is therefore possible, in such a case, to allow both cruise control functions to be activated at the same time, since only the constant speed of retarder 5 is being regulated.
• a retarder manually engaged by the driver whilst engine control unit 6 is regulating the throttle indicates that the driver considers that the speed setpoint V esetp . , towards which engine control unit 6 is regulating, is too high.
• Engine control unit 6 must therefore be automatically disengaged to enable the driver to determine a new speed setpoint V esetp . for engine control unit 6 if the cruise control function of engine control unit 6 is required. This is shown in Figure 3 in that the cruise control function of engine control unit 6 is automatically disengaged in the fifth stage 25.
• the program then returns to the initial position 20 and the different criteria in the flow chart are tested again on renewed activation of control 15 of the retarder control unit.
• the speed setpoint V rsetp . of retarder control unit 7 can be used in the fourth comparative stage 24 ' , instead of the speed of the vehicle, as a basis of comparison, and this is also shown in the fourth stage 24' in Figure 3.
• the above description relates mainly to how the cruise control functions interact. In addition they can also be used conventionally and individually without influencing each other. Similarly, they can be disengaged manually by the driver if he so chooses. The cruise control function of the engine will be disengaged when the ordinary brakes of the vehicle are activated. Both cruise control functions can also be disengaged by activating controls specially designed for this purpose. The systems therefore also provide the possibility of conventional use of these functions. In alternative designs the cruise control functions can be obtained by means of other cruise control systems which control the engine and auxiliary brake of the vehicle by other means.
• the gear changing systems can intervene and spontaneously influence the engine control system to facilitate the gear change.
• Such an influence may in some cases give rise to a reduction in torque, reduced fuel flow rate or an increase in the torque or speed, increased fuel flow rate, in order to facilitate the disengagement or engagement of gears and adjust the engine to a synchronous speed.
• the engine torque or injected fuel flow rate is used as a basis for comparing the influence of the cruise control functions, as shown in Figure 2, the modification of the fuel flow rate brought about by the gear change must not be used in this respect as a basis for comparison.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Automation & Control Theory (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Controls For Constant Speed Travelling (AREA)
• Regulating Braking Force (AREA)

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Applications Claiming Priority (2)

Publications (1)

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Country Status (5)

Cited By (10)

Families Citing this family (1)

Citations (3)

• 1992
  • 1992-10-26 SE SE9203163A patent/SE9203163L/sv not_active IP Right Cessation
• 1993
  • 1993-10-18 EP EP93924248A patent/EP0617673B1/en not_active Expired - Lifetime
  • 1993-10-18 BR BR9305688A patent/BR9305688A/pt not_active Application Discontinuation
  • 1993-10-18 WO PCT/SE1993/000851 patent/WO1994010002A1/en active IP Right Grant
  • 1993-10-18 DE DE69304303T patent/DE69304303T2/de not_active Expired - Fee Related

Patent Citations (3)

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