Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N11/00—Starting of engines by means of electric motors
  • F02N11/08—Circuits or control means specially adapted for starting of engines
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2400/00—Control systems adapted for specific engine types; Special features of engine control systems not otherwise provided for; Power supply, connectors or cabling for engine control systems
  • F02D2400/18—Packaging of the electronic circuit in a casing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N11/00—Starting of engines by means of electric motors
  • F02N11/08—Circuits or control means specially adapted for starting of engines
  • F02N11/087—Details of the switching means in starting circuits, e.g. relays or electronic switches
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2200/00—Parameters used for control of starting apparatus
  • F02N2200/02—Parameters used for control of starting apparatus said parameters being related to the engine
  • F02N2200/022—Engine speed
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2200/00—Parameters used for control of starting apparatus
  • F02N2200/04—Parameters used for control of starting apparatus said parameters being related to the starter motor
  • F02N2200/045—Starter temperature or parameters related to it
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2200/00—Parameters used for control of starting apparatus
  • F02N2200/06—Parameters used for control of starting apparatus said parameters being related to the power supply or driving circuits for the starter
  • F02N2200/063—Battery voltage
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2300/00—Control related aspects of engine starting
  • F02N2300/10—Control related aspects of engine starting characterised by the control output, i.e. means or parameters used as a control output or target
  • F02N2300/102—Control of the starter motor speed; Control of the engine speed during cranking
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2300/00—Control related aspects of engine starting
  • F02N2300/10—Control related aspects of engine starting characterised by the control output, i.e. means or parameters used as a control output or target
  • F02N2300/104—Control of the starter motor torque

Definitions

• the present invention relates to a method for driving a heat engine of a vehicle, in particular an automobile, as well as to a starter assembly making it possible to implement such a method.
• Starting a combustion engine comprises several phases of starter operation which are:
• the resistive torque of the engine is high.
• the starter drive torque is a direct function of this resisting torque.
• Ce Cr / k, where Ce is the starter drive torque, Cr the resistive torque of the heat engine and where k is the ratio between the number of teeth of the crown and the number of teeth of the pinion of the starter.
• Cb the locking torque
• the starter it would be necessary for the starter to be able to accompany the engine at a sufficiently high speed, for example 500 rpm or more, instead of 200 to 350 rpm generally provided by conventional starters.
• the object of the present invention is to further optimize this arrangement.
• a method of the above-mentioned type is characterized in that a characteristic curve is chosen for the first mode which gives a higher torque at high torque than if the characteristic curve of the second was used mode and in that one chooses as characteristic curve for the second mode a curve giving at low torque a higher drive speed than if one used the characteristic curve of the first mode.
• a parameter linked to the speed of the heat engine or of the electric motor of the starter assembly is compared with a threshold value and a change is made from one operating mode to another when this threshold value is crossed;
• a parameter linked to the charge level of the starter assembly is compared with a threshold value and one passes from one operating mode to another when this threshold value is crossed;
• the voltage of the vehicle battery and / or the temperature of the starter assembly or a temperature in the vicinity thereof is measured before the heat engine is driven by said assembly and the threshold value is determined as a function of the battery voltage and / or temperature thus measured; above a given threshold temperature, the electric starter motor is controlled directly according to the second operating mode.
• a vehicle starter in particular an automobile, comprising an electric starter motor, means for controlling the supply of the inductor winding (s) of this electric motor, drive means for driving said heat engine successively.
• at least two modes corresponding to curves of different speed / torque characteristics a first mode allowing high torques for low speeds, while a second mode allows higher speeds than the first mode for low torques, characterized in that the first mode has a higher drive speed than if the characteristic curve of the second mode were used.
• said means comprise means for controlling the supply of the inductor winding (s) of the electric motor according to two supply modes, one which corresponds to the first drive mode and which makes it possible to provide a high inductive field, the other which corresponds to the second training mode and which makes it possible to provide a lower inducing field;
• said control means comprise switch means capable of short-circuiting part of the inductor winding (s) of the electric motor;
• the circuit which controls said switch means is wholly or partly disposed in a housing which is not carried by the electric starter motor and which is connected to means carried by said electric motor by means forming cable.
• FIG. 2 is a similar graph illustrating the principle of training according to a possible embodiment of the invention
• FIG. 3 is a flowchart illustrating different stages of training in accordance with an embodiment of the invention
• Figure 4 is a schematic representation of a starter assembly according to a possible embodiment for the invention.
• FIG. 2 shows two characteristic speed / torque curves corresponding to two distinct drive modes (1), (2) obtained with the same starter assembly.
• Mode (1) corresponds to a higher blocking torque than mode (2) and has, according to one characteristic, a slope of decrease in speed as a function of the torque less than the latter.
• the drive mode (1) allows, according to the invention at high torque, a higher drive speed than with the drive mode (2).
• the driving speed Nel obtained with mode (1) for a torque Ce is greater than the speed Ne2 obtained with mode (2) for the same couple).
• the drive mode (2) which allows a higher drive speed than with the drive mode (1).
• the driving speed Ne '2 obtained with mode (2) for a torque Ce 1 is greater than the speed Ne' 1 obtained with mode (1) for the same couple).
• the electric starter motor Upon detection of the closing of the vehicle contact switch (step 1 in FIG. 3), the electric starter motor is supplied with power to operate in mode (1) (step 2).
• the speed (average or instantaneous) of the starter or of the heat engine - designated by N in the remainder of the text - is then permanently compared with a reference speed Nref which corresponds, for example to the speed for which the characteristic curves of the mode ( 1) and mode (2) intersect (step 3).
• a reference speed Nref which corresponds, for example to the speed for which the characteristic curves of the mode ( 1) and mode (2) intersect (step 3).
• a test is then continuously implemented making it possible to detect the start of the engine of the motor vehicle (step 6).
• step 7 When it is detected (during step 4 or step 6) that the engine has started, the electric motor of the starter is stopped (step 7).
• the starter starts to work in mode (1) so as to ensure the setting in motion of the thermal engine and to produce a high speed under high torque during the phase of training.
• This assembly includes an electric starter motor Me which includes an armature, as well as field coils, referenced from Bl to B4 in FIG. 4, connected in series between earth and a supply terminal B + at the positive supply voltage. of the vehicle battery.
• Me which includes an armature, as well as field coils, referenced from Bl to B4 in FIG. 4, connected in series between earth and a supply terminal B + at the positive supply voltage. of the vehicle battery.
• Winding M is a holding winding which, at its end opposite to winding A, is connected to ground, while winding A is a calling winding which at its end opposite to winding M is connected on the one hand to a point between the inductor windings Bl to B4 and the terminal B + and on the other hand, via the contact of a relay R, at a point between the windings Bl and B2 and the windings B3 and B4.
• This relay R makes it possible to have two drive modes: - in the open state, the four windings Bl to B4 are supplied and thus provide a high torque corresponding to mode (1); in the closed state, two of the inductor coils (in this case Bl and B2) are short-circuited, so that the inductor field is reduced, which allows a higher speed at low torque and corresponds to the drive mode (2).
• the speed measurement is done, in this example, at the level of a microcontroller MC, from the analysis of the duration of the voltage ripples of the vehicle network.
• the network voltage is taken from the cable coming from the contact switch (referenced by I) of the vehicle to be injected onto an input A1 of said microcontroller MC. More precisely, said input A1 is an input of the analog / digital converter of the microcontroller MC.
• a stage which includes a resistor RI and a Zener diode DZl and which makes it possible to subtract from the network voltage part of its DC component, so that the maximum voltage received on the input Al is less than the maximum acceptable voltage on said input, while the minimum voltage received on this input remains positive.
• the resistance RI of this stage is mounted between said input Al and the ground, while its diode DZl is mounted between said input Al and the contact switch I, this diode DZl being passed from input Al towards the switch
• a Zener diode DZ2 is furthermore mounted between the ground and the input Al, passing from the ground to said input Al. This diode DZ2 protects said input against possible overvoltages.
• An output of the microcontroller MC, referenced by NI, controls the gate of a MOSFET transistor T which controls the supply of the winding of the relay R.
• the microcontroller MC monitors the voltage of the vehicle network via its input A1 and calculates the derivative of the voltage it measures. Initially, the output NI remains in the low state, thus blocking the transistor T, and leaving the relay R at rest. The electric motor Me then operates in mode (1), providing a high torque for low speeds.
• the MC microcontroller sets the NI output to the high state.
• the transistor T turns on and closes the relay R, so that the starter operates in mode (2).
• the output Ni immediately returns to the low state so as to brake the armature (increase in the magnetic flux of the inductor in mode 2).
• the detection of the combustion engine start is carried out in a manner known per se: exceeding of an engine speed threshold measured from the engine computer or a specific sensor (inductive sensor on flywheel, vibration sensor, etc. ); exceeding a starter speed threshold measured by a sensor installed on the starter; detection of the disappearance of mains voltage ripples; detection of the disappearance of the intensity ripples absorbed by the starter.
• the drive which has just been described has the advantage of adapting the torque / speed characteristic so as to accompany the thermal engine in its rise in speed, in the phase of end of starting.
• the combustion engine drive is optimally performed with the highest speed of rotation for a given torque.
• the first mode has a higher drive speed than if the characteristic curve of the second mode were used.
• the transition from one drive mode to another is done by playing on the supply of the inductor winding (s).
• Other electrical solutions could be envisaged: coupling of windings of the inductor in parallel, current bypass in the armature or inductor, additional coils, etc.
• Mechanical solutions could also be envisaged: reducer with several ratios activated by an electric actuator, for example.
• the mode change reference threshold (speed Nref in the embodiments and embodiments which have just been described) is advantageously indexed at the starting temperature measured on the starter assembly or in the vicinity of this one, before a drive of the thermal engine.
• the reference threshold for changing the operating mode can be linked to the load level of the starter, the switching from one drive mode to another being for example a function of the intensity of the supply current of its inductor windings.
• the control circuit of the relay R which in particular constitute the microcontroller MC and the transistor T, is integrated on the carcass of the electric motor Me.
• the control unit could be housed in a housing separate from the rest of the starter and connected to it by cables.
• relay R can be replaced by other types of power switches, for example by a power transistor.
• the coils M and A can be replaced by a single coil controlled by a modulated width signal (PWM) according to known methods, in particular as described in patent applications FR-A-2 679 717, FR-A- 2,771,780 and FR-A-2,795,884.
• PWM modulated width signal
• the microcontroller MC in addition to the role of adapting the drive mode by the starter assembly, can integrate other known functions, such as driving the coil or coils of the relay R 0 , the realization of protections (overload protection, thermal protections, ...), etc.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Combined Controls Of Internal Combustion Engines (AREA)
• Control Of Vehicle Engines Or Engines For Specific Uses (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8845823

Family Applications (1)

Country Status (6)

Cited By (2)

Families Citing this family (5)

Citations (5)

• 2000
  • 2000-01-12 FR FR0000334A patent/FR2803633B1/fr not_active Expired - Fee Related
• 2001
  • 2001-01-10 KR KR1020017011536A patent/KR100726471B1/ko active IP Right Grant
  • 2001-01-10 EP EP01903902A patent/EP1161629B1/de not_active Expired - Lifetime
  • 2001-01-10 DE DE60109089T patent/DE60109089T2/de not_active Expired - Lifetime
  • 2001-01-10 ES ES01903902T patent/ES2239120T3/es not_active Expired - Lifetime
  • 2001-01-10 WO PCT/FR2001/000061 patent/WO2001051807A1/fr active IP Right Grant

Patent Citations (5)

Non-Patent Citations (1)

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