EP2815121A1

EP2815121A1 - Device and method for starting a motor vehicle combustion engine equipped with a voltage measurement system

Info

Publication number: EP2815121A1
Application number: EP13710453.5A
Authority: EP
Inventors: Jean-Sébastien Metral; Stéphane PLAIDEAU
Original assignee: Valeo Equipements Electriques Moteur SAS
Current assignee: Valeo Equipements Electriques Moteur SAS
Priority date: 2012-02-17
Filing date: 2013-02-14
Publication date: 2014-12-24
Also published as: FR2987082B1; WO2013121152A1; FR2987082A1

Abstract

The invention essentially consists in a starter device comprising: - a starter (1) of a combustion engine of a motor vehicle equipped with a battery that powers the various electrical elements of the vehicle, said starter (1) comprising a drive member (13) capable of a translational movement from a rest position into an active position in which the drive member interacts with a drive element of the engine, and a contact switch (23) for moving the drive member (13); characterized in that the starter device further comprises - a system (46) for measuring the battery voltage; and - a control unit (44) for controlling the translational movement of the drive member (13) according to measurements output by the voltage measurement system (46).

Description

DEVICE AND METHOD FOR STARTING A THERMAL MOTOR OF A MOTOR VEHICLE WITH A VOLTAGE MEASUREMENT SYSTEM

[01] TECHNICAL FIELD [02] The invention relates to the field of starters for a motor vehicle engine. The invention finds a particularly advantageous, but not exclusive, application with vehicles equipped with the function of stopping and restarting the engine (so-called "stop and start" function) according to which the engine of the vehicle is stopped due to traffic conditions (especially during a stop at a red light) and then restarted to save fuel.

[03] STATE OF THE ART

[04] A starter generally comprises an electric motor associated with a drive assembly of the internal combustion engine. The drive assembly is most often adapted to be coupled to the moving parts of the internal combustion engine during a start-up phase of the latter and to be uncoupled from the internal combustion engine when the latter is running. [05] For this purpose, the starter comprises an electromagnetic switch adapted to, on the one hand, drive the power supply of the electric motor and, on the other hand, control the coupling and uncoupling of the drive assembly with one of the moving parts of the internal combustion engine. The drive assembly comprises a launcher associated with a drive member typically taking the form of a drive gear adapted to mate with the movable member of the engine. The drive gear is movable in translation between a disengaged position and a coupled position. The launcher is mobile in rotation on itself and is movable in axial translation between a rest position and a driving position. The launcher is moved between these rest and drive positions by means of a lever operated by the electromagnetic switch. [06] For starters using the "stop and start" technology, it is important to minimize the starting time of the combustion engine after receiving a request, for example by pressing the accelerator pedal or any other other suitable activation means. To this end, it is known to dissociate the engagement phase of the drive member with respect to the training phase of this body. Thus, when a stop phase of the engine is detected, the drive member is engaged between the teeth of the engine crown while the engine is still rotating, and as soon as a request to start the engine motor is received from the driver, the starter rotates the drive member.

[07] As shown in Figure 1, the stopping phase of the engine which corresponds to the time interval between a stop command of the engine and the actual stopping of the latter is formed of a first window F1 in which the speed of the engine decreases while remaining strictly positive and a second window F2 in which the speed has oscillations around the zero speed before becoming zero. The sign of the rotational speed of the engine depends on the direction of rotation of the engine: it is positive when the motor rotates in the usual direction of rotation and negative when it rotates in the opposite direction. Note that the oscillation around the zero speed corresponds to a phase called "swing phase" in which the crankshaft can rotate in the opposite direction also called "inverted rotation" during the last descent of one or more pistons. [08] The starter may be damaged in the case where the drive unit moves into the engagement position when the motor has a speed too high (in particular greater than 300 revolutions / min) or when the engine changes from direction of rotation in the swing phase F2. [09] PURPOSE OF THE INVENTION

The object of the invention is to allow engagement of the drive member, when the heat engine is present, in a phase stop, a strictly positive speed adapted but lower speeds that may damage the starter.

[011] For this purpose, a system is used for measuring the voltage of the battery of the vehicle and the engagement of the drive member is controlled according to the measurement of the voltage on the battery.

[012] Indeed, the invention is based on the principle that, during the stopping phase of the engine, the voltage of the vehicle battery typically varies in correspondence with the speed of rotation of the engine. Indeed, stopping the heat engine causes voltage variations on the battery. As a result, it is possible to detect voltage variations corresponding to the stopping of the heat engine. Then, the system can therefore control the displacement in translation of the drive member when the rotation speed of the heat engine is in a range of rotational speeds of the motor adapted to a safe engagement of the drive member between the teeth of the motor crown.

[013] The invention thus provides an integrated product for detecting itself the range of speeds adapted to the engagement of the drive member, without having to use a reported sensor associated for example with the heat engine and which would require a configuration after manufacture of the starter. The starting device according to the invention is ready to be used as soon as it leaves the factory.

[014] The invention therefore relates to a starting device comprising - a starter of a combustion engine of a motor vehicle, the vehicle being provided with a battery supplying the power supply of various electrical elements of the vehicle, the starter comprising a movable drive member in translation from a rest position to an active position in which the drive member cooperates with a driving element of the motor, characterized in that the starting device further comprises - a system of measurement of battery voltage, and

a control unit arranged for detecting, by means of information received from the voltage measuring system, measured voltage variations corresponding to predetermined voltages, and in that that these variations of voltages at predetermined voltages correspond to a range (P2) of rotational speeds of the heat engine adapted to the change of position of the drive member (13),

a switch for moving the drive member, and

wherein the control unit (44) is arranged to control the switch (23) to move the drive member (13) from the home position to the active position when the control unit (44) detects by through the voltage measuring system, the measured voltage variations corresponding to predetermined voltages. [015] In one embodiment, the voltage measuring system is able to measure voltages on the positive terminal of the battery applied to a terminal of the starter and in that the control unit is able to determine variations in the measured voltages. .

[016] In one embodiment, the voltage measuring system is integrated in the control unit.

[017] In one embodiment, the voltage measuring system is integrated in a micro-coil of the contactor.

[018] In one embodiment, the starter comprises a contactor adapted to move the drive member, the control unit is adapted to control the switch to move the drive member from the rest position to the active position when the control unit detects measured voltage variations corresponding to predetermined voltages and is adapted from its variations of voltage to move the drive member when the rotational speed of the heat engine corresponds to a range of speeds of rotation of the heat engine adapted to the change of position of the drive member.

[019] In one embodiment, the range of rotational speeds adapted is between 50 and 300 revolutions / min, and preferably between 50 and 100 rev / min. [020] In one embodiment, the control unit compares the measured voltages and detects a swing phase when the voltages measured corresponds to a stopping phase of the heat engine, and in that it delays during a predetermined time delay from the stop phase detection and in that it controls to move the drive member after a period beginning at the stop phase detection and ending at a threshold corresponding to the time for the heat engine to have a rotational speed of the engine adapted to the change of position of the drive member.

[021] In one embodiment, the contactor comprises a contact plate movable by a movable core, the contact plate being opposite two terminals, one of which is connected to the power supply of the electric motor and the other is connected to at least one a broom belonging to the electric motor of the starter,

said contactor can present:

a state of rest in which the contact plate is electrically and mechanically isolated from the two terminals,

a state of engagement in which the contact plate is in mechanical and electrical contact with one of the terminals while the other terminal is isolated from the contact plate, and

a power state in which the contact plate provides an electrical connection between the two terminals,

the control unit being able to control the transition from the state of rest to the state of engagement when the driving member moves from the rest position to the active position, and

the control unit being able to control the transition from the state of engagement to the power state when said control unit detects a start request of the heat engine linked for example to a request for acceleration of the driver's share.

[022] In one embodiment, the control unit is pressed against the face of the contact plate opposite the face facing the contact terminals.

[023] The invention furthermore relates to a method for controlling a starting device comprising a starter of a combustion engine of a motor vehicle, the starter comprising a driving member. movable in translation from a rest position in which the drive member is disengaged from the drive element of the heat engine to an active position in which the drive member cooperates with a drive element of the heat engine, and a contactor adapted to move the drive member,

characterized in that it comprises the following steps:

- measure a voltage of the battery, and

a detection step by means of the voltage measuring system, measured voltage variations corresponding to predetermined voltages, and in that these voltage variations at predetermined voltages correspond to a range of rotational speeds of the adapted thermal engine. at the change of position of the drive member,

a step of controlling a starter contactor moving the drive member from the rest position to the active position when a voltage variation is detected from the voltage measurements corresponding to a range of speeds; of rotation of the heat engine adapted this change of position of the drive member.

[024] According to one implementation, the method comprises the step of controlling a starter contactor to move the drive member from the rest position to the active position when a voltage change is detected at from the voltage measurements corresponding to a range of speeds of rotation of the heat engine adapted this change of position of the drive member. [025] According to one implementation, the method comprises a stop phase detection phase of the thermal engine by comparing the measured voltage values, a delay step from the detection of the stop phase and a step for controlling a starter switch to move the drive member from the home position to the active position after a period of time for the thermal engine to be in a rotational speed range adapted for position change of the drive member. [026] According to one embodiment, the range of rotation speeds adapted is between 50 and 300 revolutions / min, and preferably between 50 and 100 rev / min.

[027] According to one embodiment, the contactor comprises a contact plate displaceable by a movable core, the contact plate comprising a face opposite two terminals, one of which is connected to the power supply of the electric motor and the other is connected to at least one broom belonging to the electric motor of the starter,

said contactor being able to present:

the starter comprising the following steps:

- control the transition from the state of rest to the state of engagement when the drive member moves from the rest position to the active position, and - control the transition from the commitment state to the power state when a start request of the heat engine is detected.

[028] The invention furthermore relates to a method of controlling a heat engine equipped with a starting device according to the invention, characterized in that, when the heat engine enters a stopping phase, it comprises the following steps:

determination by the control unit of the battery voltage variations and a comparison of these voltage variations with predetermined voltage variations corresponding to a rotation speed of the heat engine, and in that

when the determined battery voltage variations are within a predetermined voltage variation range corresponding to a speed greater than a first speed threshold, a start request step of the heat engine is detected, an injection control step to restart the engine, when the determined battery voltage variations are in a predetermined voltage variation range corresponding to a predetermined thermal engine rotational speed is located in a first speed range having as the upper limit the first speed threshold and as the lower limit a second speed threshold, a step of preventing activation of the starter,

when the battery voltage variations the battery voltage variations determined are in a predetermined range of voltage variations corresponding to a rotation speed of the thermal engine in a second range of rotational speeds having as upper limit the second threshold a third speed threshold, a step of controlling the switch in the state of engagement to move the drive member from the rest position to the active position, the switch then passing from the state of rest in the state of engagement, and

when the starter device detects a start request of the heat engine linked for example to pressing the accelerator pedal and the driving member is in the active position, a step of controlling the passage of the contactor of the state commitment to the power state to power the electric motor of the starter.

[029] According to one implementation, the first speed threshold is of the order of 500 revolutions / min, the second speed threshold is of the order of 300 revolutions / min, and the third speed threshold is of the order of order of 50 turns / min.

[030] BRIEF DESCRIPTION OF THE FIGURES [031] The invention will be better understood on reading the description which follows and on examining the figures which accompany it. These figures are given for illustrative but not limiting of the invention.

[032] Figure 1 already described shows a graphical representation of the evolution, as a function of time, the speed of rotation of the engine during a stopping phase of the latter;

[033] Figure 2 shows a longitudinal sectional view of a starter device according to the invention; [034] Figures 3a-3c show the different states that can take the switch of the starter according to the invention;

FIG. 4 represents steps of a control method of a heat engine equipped with the starting device according to the invention as a function of the different ranges of speeds of rotation of the heat engine in its stopping phase.

[036] The identical, similar or similar elements retain the same reference from one figure to another.

[037] DESCRIPTION OF AN EXEMPLARY EMBODIMENT OF THE INVENTION

[038] Figure 2 shows an example of a starter 1 according to the invention in a rest position. The starter 1 is of the "launcher" type. The starter 1 comprises an electric motor comprising firstly a rotor 3, also called armature, mounted on a rotor shaft 5 rotatable about its longitudinal axis X and secondly a stator 7, also called inductor around the rotor 3. The rotor shaft 5 has its rear end mounted in a bearing 5a of a bearing 1 1b at the rear of the starter 1 (called rear bearing).

Behind the rotor 3, is mounted on the shaft of the rotor 5, a collector 9 comprising contact parts electrically connected to the rotor 5.

[040] The stator 7 is carried by a carcass January 1, also called starter frame. The stator 7 may comprise a plurality of permanent magnets. Alternatively, these magnets are replaced by electromagnets.

[041] The starter 1 further comprises a pinion 13 mounted idly on a drive shaft 15. The drive shaft 15 has one of its ends mounted on the bearing 1 1 a front comprising one or more needle bearings 15a on the front part of the starter 1.

[042] In the remainder of the description, the terms "front" and "rear" are, in the longitudinal direction of the X axis of the drive shaft 15 or rotor shaft 5, such as a front face of an organ is the face looking to a front bearing 1 1 a and the rear face is the side facing the rear bearing 1 1 b.

[043] The pinion 13 is mounted on the drive shaft 15 by means of one or more bearings, in this case two needle bearings 151. The pinion 13 is mounted to translate along the X axis with respect to the drive shaft 15 a rest position which corresponds to the position shown in Figure 2 at an active position. In the active position, the pinion 13 is intended to drive in rotation a toothed wheel 100 driving in rotation a crankshaft of a heat engine (not shown). In this case, the X axis of the drive shaft 15 is substantially the same as the X axis of the rotor shaft 5 but could be different, as in the examples described below.

[044] The starter 1 further comprises a pinion movement system 13 from its rest position to its active position and vice versa. This displacement system comprises a contactor 23 and a fork-shaped lever described hereinafter.

[045] The starter 1 further comprises a reduction system 17 mounted between the rotor shaft 5 and the drive shaft 15, one end of which is connected to the rotor shaft 5 and the other end is connected to the driving shaft 15. The reducing system 17 is in this case an epicyclic gear train but can be any other type of gearbox. For example, the reduction system 17 could comprise two gears, one of which is secured to the shaft of the rotor 5 and the other of the drive shaft 15. In this example, the two axes of the rotor shaft 5 and the drive shaft 15 are offset in parallel. According to another example, the reduction system 17 may be geared left or gear concurrent. In these two types of reduction system 17, the axis of the drive shaft 15 and the axis of the rotor shaft 5 are respectively concurrent or neither parallel nor concurrent. [046] A freewheel referenced 16 is connected on the one hand mechanically to the pinion 13 and on the other hand to the drive shaft to avoid damaging the starter when the pinion 13 is driven at high speeds by the engine. Alternatively, the freewheel 16 is replaced by a coupling system that can move from a uncoupled state to a coupled state and vice versa. In the coupled state, the rotor shaft 5 is secured in the direction of starting rotation to the pinion 13. In the uncoupled state, the pinion 13 is disengaged in both directions of rotation of the rotor shaft 5. In other words the pinion is crazy relative to the drive shaft when in the uncoupled position also called rest position. In this case, this coupling system makes it possible to couple the pinion 13 to the drive shaft 15 when the pinion 13 moves from the rest position to the active position. [047] A group of brushes 19a and 19b is provided for the power supply of the rotor winding 3. At least one of the brushes 19b is electrically connected to the starter 1, for example the carcass January 1, and at least one Another of the brushes 19a is electrically connected to an electrical terminal 21a of the contactor 23, for example via a wire 22. The brushes 19a and 19b are rubbing on the collector 9 when the rotor 3 is rotating. The starter 1 may comprise a plurality of brushes.

[048] The switch 23 comprises, in addition to the terminal 21a connected to the brush 19a, a terminal 21b positive to be connected via an electrical connection element to a positive power supply V + of the vehicle, including a battery, not shown. This battery charged by an alternator driven by the engine of the vehicle provides power to various electrical elements of the vehicle, such as air conditioning, headlights, power windows, etc.

[049] The switch 23 comprises a movable contact plate 25 for electrically connecting the terminals 21b and 21a to supply the electric motor. The contactor 23 is also able to actuate a fork 27 to move the pinion 13 along the X axis of the drive shaft 15 relative to the drive shaft 15 from the rest position to the active position and vice versa . For this purpose, the contactor 23 also comprises a movable core 29, a fixed core 28, a fixed coil 26, a movable control rod 24 and a movable rod 241.

[050] The control rod 24 passes through the fixed core 28 which serves as a guide. This control rod 24 has its front end in support on the fixed core 28 and its rear end attached to the contact plate 25. The control rod 24 is subjected to the action of a compressed contact spring (not referenced) between a shoulder of the control rod 24 and the contact plate 25 to move the latter to the disconnected position. This spring is compressed when the movable core 29 is in a so-called magnetized position to ensure electrical contact of the contact plate with the terminals 21a and 21b.

[051] The movable rod 241 is fixed at its front end to the fork 27. When the coil 26 is energized, the movable core 29 is attracted to the fixed core 28 to be in magnetized position. Its displacement simultaneously drives the movable rod 241, the contact plate 25 and the control rod 24 towards the rear. The movable rod 241 is further subjected to a tooth against tooth spring 291 housed inside the movable core 29 and surrounding the movable rod 241. This tooth against tooth spring 291 is supported on a front shoulder of the movable rod 241 and a rear shoulder of the movable core 29. This tooth against tooth spring 291 compresses when the movable core moves towards the fixed core and when the fork 27 can no longer advance the pinion 13. The fork 27 can not advance when the pinion 13 is blocked in translation along the X axis in the direction of the toothed wheel 100 by one or more teeth of the toothed wheel 100. This blocked state is called "tooth against tooth position". The compression of the tooth against tooth spring 291 absorbs shocks while applying a force on the fork 27 transmitted to the pinion 13 to the engagement position. In addition, this makes it possible to advance the contact plate towards terminals 21a and 21b.

[052] The switch 23 further comprises a return spring 290, bearing on the fixed coil 26 and the movable core 29 to urge it forward to its rest position and simultaneously move the fork 27 to the pinion 13 is in the rest position. [053] The contactor 23 may have the following states:

a state of rest in which the contact plate 25 is electrically and mechanically isolated from the two terminals 21a, 21b (cf FIG. 3a), a state of engagement in which the plate 25 is in mechanical and electrical contact with one of the terminals 21a, 21b, the other terminal 21a, 21b being electrically isolated from the contact plate 25 (see FIG. ), and

- A power state in which the contact plate 25 provides an electrical connection between the two terminals 21a and 21b (see Figure 3c).

The different states are obtained by means of a controlled connection establishment system 41 comprising a micro-coil whose operation is more fully detailed in the French patent application number FR1162255. Alternatively, the system 41 may have any other electrical or mechanical configuration to operate the switch 23 in the various states described below.

[054] A control unit 44 is able to control the contactor 23 in particular according to the measurements returned by a system 46 for measuring a voltage delivered by the battery. This control unit 44 is pressed against the front face of the contact plate 25 opposite the face of the contact plate facing in contact with the terminals in the connected position.

[055] The voltage measurement system 46 makes it possible to detect voltage variations VAR of the positive voltage V + of the battery. These variations VAR of detected voltage are detected when the starter is in phase of stop. The control unit can therefore control the displacement in translation along the X axis of the drive shaft of the drive member (13) when the rotational speed of the heat engine in the stop phase is in a speed range adapted to the engagement of the drive pinion 13 during the stopping phase of the motor. The system 46 takes for example the form of a voltmeter.

[056] The positive electric potential of the battery V + being applied to the terminal 21a, the voltage measurement system 46 can be integrated into the control unit 44. Preferably, the voltage measuring system 46 is integrated in the the micro-coil of the system 41. Alternatively, the voltage measurement system 46 may be installed in any other location of the starter 1. [057] Hereinafter described, with reference to FIG. 4, during the stopping phase of the heat engine, a first embodiment of a control method of the starting device according to the invention as a function of the different ranges of rotational speeds of the engine. [058] When the control unit 44 detects, by means of the voltage measuring system 46, during a stopping phase, voltage variations of the potential V + corresponding to a speed of rotation of the thermal engine greater than a first threshold S1 for example of the order of 500 revolutions / min, and that the control unit 44 detects a request for starting the engine, for example by detecting a pressure on the accelerator pedal, no appeal is made to the starter 1 to restart the engine. Indeed, in this case, the control of the injection in a step 1 10 is enough to restart the engine.

[059] When the control unit 44 detects, by means of the voltage measuring system 46, voltage variations of the potential V + corresponding to a speed of rotation of the heat engine lying in a range P1 having as an upper limit the first threshold S1 and as the lower limit a second threshold S2 of the order of 300 rpm, the control unit goes into standby mode and measures the voltage variations until it is in a range of voltages variations corresponding to a speed range P2 adapted to the engagement of the pinion 13. The step 1 1 1 according to which the control unit 44 waits to reach the range P2 is implemented that the control unit 44 detects or not, in the range P1, a request to start the engine.

[060] When the control unit 44 detects, by means of the voltage measuring system 46, voltage variations of the potential V + corresponding to a rotation speed of the heat engine lying in a range P2 adapted, the unit of control 44 controls, in an engagement step 1 12, the switch 23 so as to move the pinion 13 from the rest position to the active position. The switch 23 then goes from the state of rest to the state of engagement. The range P2 has as upper limit the second speed threshold S2 (300rpm) and as the lower limit one third speed threshold S3 for which we are sure that the engine is not in the swing phase. This third threshold S3 speed is of the order of 50rpm. Preferably, the range P2 is between 100 and 50rpm. [061] Then, when said control unit 44 detects a start request of the engine linked for example to a pressure on the accelerator pedal, the control unit 44 controls the passage of the contactor 23 of the state of the engine. commitment to the power state to activate the electric motor of the starter to drive in rotation the drive pinion 13. In the case where the request to start the engine is performed before the engagement of the pinion 13, the control unit 44 controls the passage of the switch from the engagement state to the power state just after engagement of the teeth of the pinion 13 between the teeth of the wheel 100. [062] The invention thus enables to avoid damaging the starter 1 by prohibiting the engagement of the pinion at too high speeds or in the swinging phase of the engine during which the direction of rotation of said engine can be reversed.

[063] In addition, the starting system according to the invention is autonomous insofar as said starting system itself identifies, with the aid of the voltage measuring system 46, the speed range adapted to the engagement. drive pinion 13, without having to resort to an external sensor that may require a calibration of the control unit 44 of the starter 1. [064] A second method of controlling the starting device according to the invention will now be described according to the different ranges of rotation speeds of the heat engine.

[065] When the heat engine goes into the off phase, there are voltage variations across the battery. When the control unit 44 detects, by means of the voltage measuring system 46, a stopping phase, by measuring voltage variations of the potential V + which are in a range of voltage variations corresponding to a stopping phase, it triggers a delay T1.

[066] During this delay, if during a first period P1 corresponding to a decrease in the speed of rotation of the engine but which is greater than a first threshold S1 for example of the order of 500 revolutions / min, and that the control unit 44 detects a request to start the engine, for example by detecting a pressure on the accelerator pedal, the control unit remains in delay and compares the measured voltages until the voltage variations measured correspond to a re-start the engine.

[067] Indeed, in this case, the control of the injection of fuel into the engine in a step 1 10 is sufficient to restart the engine.

[068] During the time delay T1, during a second successive period P2 of the period P1, and that the voltage variations are not in a range of voltage variation corresponding to a restart of the heat engine, the control unit 44 compares the measured voltages, by means of the voltage measuring system 46, until the delay T1 reaches a second threshold S2 (greater than S1) corresponding to the time for the heat engine in the stopping phase to have its speed rotation of the order of 300 rpm. If the control unit detects a request to start the engine, for example by detecting a press on the accelerator pedal, it stores the status.

[069] During the delay T1, during a third period P3 successive period P2, the control unit 44 controls, in an engagement step 1 12, the switch 23 so as to pass the pinion 13 of the position rest at the active position. The switch 23 then goes from the state of rest to the state of engagement. The period P3 corresponds to a period during which the thermal engine in the stopping phase has a rotation speed between a speed threshold upper limit S2 (300rpm) and a lower limit a third speed threshold S3 for which one is sure that the engine is not in phase swinging. This third threshold S3 speed is of the order of 50rpm. Preferably, the range P3 is between 100 and 50rpm.

[070] Then, when said control unit 44 detects a request for starting the heat engine linked for example to pressing the accelerator pedal, the control unit 44 controls the passage of the contactor 23 of the state of the engine. commitment to the power state to activate the electric motor of the starter to drive in rotation the drive pinion 13. In one embodiment, in the case where the start request of the engine is performed before the 13, the control unit 44 memorizes it and controls the passage of the switch from the engagement state to the power state just after engagement of the teeth of the pinion 13 between the teeth of the wheel 100.

[071] The invention thus avoids damaging the starter 1 by prohibiting the engagement of the pinion at too high speeds or in the swing phase of the engine during which the direction of rotation of said engine can be reversed .

[072] In addition, the starting system according to the invention is autonomous insofar as said starting system itself identifies, with the aid of the voltage measuring system 46, the speed range adapted to the engagement. drive pinion 13, without having to resort to an external sensor that may require a calibration of the control unit 44 of the starter 1.

[073] Note that the various thresholds and rotational speed ranges of the heat engine are indicated in the description above as an indication and could vary in a range of about 5 to 10 percent of their indicated value.

[074] It is also noted that the drive pinion 13 may be at a variable distance from the drive wheel 100, for example between 1 and 6 mm. Having knowledge of the speed of displacement of the drive gear 13 and the duration of the stopping phase of the motor, it is possible to determine the moment when it is necessary to control the passage of the current in the fixed coil 26 to allow pinion engagement 13 at the rotational speed adapted to the wheel 100 within the speed range P2.

Claims

1. Starter device comprising

a starter (1) of a thermal engine of a motor vehicle, the vehicle being provided with a battery providing power for various electrical elements of the vehicle, the starter comprising a drive member (13) movable in translation; from a rest position to an active position in which the driving member cooperates with a driving element of the motor, characterized in that the starting device further comprises

a system (46) for measuring the voltage of the battery,

a control unit (44) arranged to detect, by means of the voltage measuring system, measured voltage variations corresponding to predetermined voltages, and in that these voltage variations at predetermined voltages correspond to a range (P2 ) rotational speeds of the heat engine adapted to the change of position of the driving member (13),

a switch for moving the drive member, and

wherein the control unit (44) is arranged to control the switch (23) to move the drive member (13) from the home position to the active position when the control unit (44) detects by through the voltage measuring system, the measured voltage variations corresponding to predetermined voltages. 2. Starting device according to claim 1, characterized in that the voltage measuring system (46) is able to measure voltages on the positive terminal (V +) of the battery applied to a terminal (21b) of the starter ( 1) and in that the control unit is able to determine variations of the measured voltages.

3. Device according to claim 1 or 2, characterized in that the system (46) for measuring voltage is integrated in the control unit (44).

4. Device according to claim 1 or 2, characterized in that the voltage measuring system (46) is integrated in a micro-coil of the contactor (23).

6. Device according to claim 5, characterized in that the range of rotational speeds (P2) is between 50 and 300 revolutions / min, and preferably between 50 and 100 revolutions / min. 7. Device according to one of the preceding claims, characterized in that the control unit compares the measured voltages and detects a swing phase when the measured voltages corresponds to a stopping phase of the engine, and in that it time delay during a predetermined time delay (T1) from the stop phase detection and in that it controls to move the drive member after a period (P1 and P2) starting at the stop phase detection and terminating at a threshold S3 corresponding to the time for the engine to have a rotational speed of the engine adapted to the change of position of the drive member (13).

8. Device according to one of claims 5 to 7, characterized in that the contactor (23) comprises a contact plate (25) movable by a movable core (29), the contact plate (25) being opposite two terminals (21 a, 21 b) one of which (21 a) is connected to the power supply of the electric motor and the other (21 b) is connected to at least one broom belonging to the electric motor of the starter (1),

said contactor (23) can present:

a state of rest, in which the contact plate (25) is electrically and mechanically isolated from the two terminals (21 a, 21 b),

a state of engagement in which the contact plate (25) is in mechanical and electrical contact with one of the terminals (21a) while the other terminal is isolated from the contact plate (25), and

a supply state in which the contact plate (25) provides an electrical connection between the two terminals (21 a, 21 b), the control unit (44) being able to control the transition from the state of rest to the state of engagement when the drive member (13) moves from the rest position to the active position, and

the control unit (44) being able to control the transition from the state of engagement to the supply state when said control unit

(44) detects a start request of the heat engine related for example to an acceleration request from the driver.

9. Device according to claim 8, characterized in that the control unit (44) is pressed against the face of the contact plate (25) opposite the face facing the contact terminals.

10. A method of controlling a starting device comprising a starter (1) of a thermal engine of a motor vehicle, the starter comprising a drive member (13) movable in translation from a rest position in which the drive member is disengaged from the drive element of the heat engine to an active position in which the drive member cooperates with a drive element of the heat engine,

characterized in that it comprises the following steps

- measure a voltage of the battery,

a detection step by means of the voltage measuring system, measured voltage variations corresponding to predetermined voltages, and in that these voltage variations at predetermined voltages correspond to a range (P2) of rotation speeds of the a heat engine adapted to the change of position of the driving member (13), and

a step of controlling a contactor (23) of the starter moving the driving member (13) from the rest position to the active position when detecting a voltage variation from the voltage measurements. corresponding to a range of rotational speeds of the heat engine adapted this change of position of the drive member (13). - Controlling the displacement of the drive member (13) in translation as a function of the voltage measurements of the battery.

1 1. A method according to claim 10, characterized in that it comprises the step of controlling a contactor (23) of the starter to move the drive member (13) from the rest position to the active position during a detection a variation of voltage from the voltage measurements corresponding to a range of rotational speeds of the heat engine adapted this change of position of the drive member (13).

12 Process according to claim 10, characterized in that it comprises a step of stopping phase detection of the thermal engine by comparing the measured voltage values, a delay step from the detection of the stopping phase and a step of controlling a contactor (23) of the starter to move the drive member (13) from the rest position to the active position after a period (P1 and P2) corresponding to the time for the engine to be in a rotational speed range adapted for the change of position of the drive member (13).

12. The method of claim 1 1, characterized in that the range of rotational speeds adapted is between 50 and 300 revolutions / min, and preferably between 50 and 100 rev / min.

13. The method of claim 1 1 or 12, characterized in that the contactor (23) having a contact plate (25) movable by a movable core (29), the contact plate (25) comprising a face opposite two terminals (21 a, 21 b) one of which (21 a) is connected to the power supply of the electric motor and the other (21 b) is connected to at least one broom belonging to the electric motor of the starter (1),

said contactor (23) being able to present:

a state of rest in which the contact plate (25) is electrically and mechanically isolated from the two terminals (21 a, 21 b), a state of engagement in which the contact plate (25) is in mechanical and electrical contact with one of the terminals (21a) while the other terminal is isolated from the contact plate (25), and

a supply state in which the contact plate (25) provides an electrical connection between the two terminals (21 a, 21 b),

the starter comprising the following steps:

- control the transition from the state of rest to the state of engagement when the drive member (13) moves from the rest position to the active position, and

- control the transition from the commitment state to the power state when a start request of the engine is detected.

14. A method of controlling a heat engine equipped with a starting device according to one of claims 1 to 9, characterized in that, when the heat engine enters a stop phase, it comprises the following steps:

when the determined battery voltage variations are within a predetermined voltage variation range corresponding to a speed greater than a first speed threshold, a start request step of the heat engine is detected, an injection control step to restart the engine,

when the determined battery voltage variations are in a predetermined voltage variation range corresponding to a predetermined thermal engine rotational speed is located in a first speed range having as the upper limit the first speed threshold and as the lower limit a second speed threshold, a step of preventing activation of the starter,

when the battery voltage variations the battery voltage variations determined are in a predetermined range of voltage variations corresponding to a rotational speed of the thermal engine in a second range of rotational speeds having as the upper limit the second speed threshold and as the lower limit a third speed threshold, a step of controlling the switch in the engaged state to move the drive member from the rest position to the active position, the contactor then passing from the state of rest to the state of engagement, and

15. Method according to claim 14, characterized in that the first speed threshold is of the order of 500 revolutions / min, the second speed threshold is of the order of 300 rpm, and the third speed threshold. is of the order of 50rpm.