Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
  • F01L9/20—Valve-gear or valve arrangements actuated non-mechanically by electric means
  • F01L9/26—Driving circuits therefor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
  • F01L9/20—Valve-gear or valve arrangements actuated non-mechanically by electric means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
  • F01L9/20—Valve-gear or valve arrangements actuated non-mechanically by electric means
  • F01L9/21—Valve-gear or valve arrangements actuated non-mechanically by electric means actuated by solenoids
  • F01L2009/2103—Valve-gear or valve arrangements actuated non-mechanically by electric means actuated by solenoids comprising one coil
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
  • F01L9/20—Valve-gear or valve arrangements actuated non-mechanically by electric means
  • F01L9/21—Valve-gear or valve arrangements actuated non-mechanically by electric means actuated by solenoids
  • F01L2009/2115—Moving coil actuators

Definitions

• the invention relates to the control of the valves in an internal combustion engine. It relates, more specifically, a valve actuation system for such an engine.
• An internal combustion engine is supplied during each cycle with a mixture comprising air and fuel (or fuel mixture).
• Such an engine comprises at least one cylinder defining a combustion chamber, this combustion chamber being delimited, in an upper part, by a cylinder head, and in a lower part, by a piston movable within the cylinder.
• the engine comprises, for each cylinder, at least one intake valve and an exhaust valve.
• a valve 5 comprises a rod at the end of which is formed a head.
• Each valve is movable in translation relative to the cylinder head of the engine between a closed position in which the head of the valve rests against a seat to close an intake duct (or, respectively, an exhaust duct) and a position open0 in which the head is spaced from the seat for communicating the combustion chamber with the intake duct (or respectively with the exhaust duct).
• the control of the valves must meet the following constraints. First, the movement of the valves must be fast and accurate, to facilitate admission or evacuation of gases respectively.
• valve stroke must be sufficient to ensure a high flow of gas, whether admission or evacuation.
• forces transmitted to the valves must be important (especially evacuation) to overcome the pressure prevailing0 in the combustion chamber.
• control system must be reliable to avoid any loss of power due to a malfunction thereof.
• valves in the internal combustion engines
• an actuating system comprising one or more camshaft (s) which drive the valves, either directly or indirectly through through rockers.
• a camshaft is rotatably coupled to the crankshaft by a timing belt or chain.
• An alternative valve control technique is electromagnetic actuation.
• each valve is driven by means of an electromagnetic actuator.
• Each actuator thus comprises one or more magnets that generate a magnetic field in which there is a coil carrying an electric current, the valve thus being able to move vertically in one direction, by the force of Laplace, when the coil is energized. by a positive current, and respectively in the opposite direction when it is supplied by a negative current.
• Each electromagnetic actuator is controlled electrically by a control device which is itself controlled by a computer (also called engine control).
• the computer is connected to different sensors that provide real-time data on the engine and in particular on the position of the crankshaft and the position of each valve relative to the cylinder head.
• the controller and the computer are used to synchronize the valves with other engine components such as pistons.
• a second phase in which the power supply of the coil is cut, upstream of the open position, to generate a negative current from the inertia stored by the valve, the negative current for braking the valve; a third phase in which the coil of the actuator is supplied with a negative current to allow the acceleration of the valve towards the closed position;
• a fourth phase in which the power supply of the coil is cut, upstream of the closed position, to generate a positive current from the inertia stored by the valve, the positive current for braking the valve.
• the electromagnetic actuator comprises a coil fixed with respect to the yoke, this coil being electrically powered during the first and third phases, and surrounding a movable magnet on which the valve is fixed.
• this document also proposes, during the second and fourth phases, storing the energy of the currents induced in a capacitor. The stored energy is then reinjected during the first phases and fourth phases, thereby reducing the energy supplied by the power supply during these phases.
• Such an architecture requires for each electromagnetic actuator the use of a capacitor for storing energy.
• Such capacitors have a non-negligible bulk, typically of the order of 10 cm 3 per capacitor, this space increasing in proportion to the number of electromagnetic actuators.
• the use of a capacitor by electromagnetic actuator also implies a non-negligible mass additional cost to manufacture.
• such capacitors must be integrated near the actuators and therefore the engine, the latter being subject to significant thermal variations. From a thermal point of view, such components can therefore also be subject to strong temperature variations, which can damage them.
• An objective is to provide a valve actuating system to overcome all the aforementioned drawbacks while optimizing the energy consumption of this system.
• valve actuation system for an internal combustion engine, this system comprising
• a first valve this first valve being actuated by a first electromagnetic actuator, said first electromagnetic actuator comprising a magnet generating a magnetic field and an electrically energized coil immersed in said magnetic field, the electrical power supply of the coil allowing alternately managing phases of accelerating and deceleration phases of the first valve, this power supply being carried out by a control device connected to the first electromagnetic actuator, said control device comprising
• control device electrically supplies the coil to provide an acceleration phase to the first valve
• control device does not electrically power the coil to provide a deceleration phase to the first valve, and collects during this phase an induced electrical energy generated by the coil;
• this second valve being actuated by a second electromagnetic actuator, said second electromagnetic actuator, comprising at least one magnet generating a magnetic field and an electrically powered coil immersed in said magnetic field, the power supply of the coil for managing alternatively acceleration phases and deceleration phases of the second valve;
• the induced electrical energy generated by the coil of the first electromagnetic actuator and collected by the control device is transmitted by this device to the coil of the second electromagnetic actuator, so as to use this electrical energy for the acceleration phase of the second valve.
• this system comprises a computer configured for
• control device is made from an H bridge comprising electronic switching components, the H bridge being electrically connected to the terminals of the coil of the first electromagnetic actuator so as to control the flow direction of the electric current in the coil.
• the computer is configured to control the state of the electronic switching components of the H bridge, via pulse width modulated signals, these signals being provided by the computer according to the identification of the acceleration and deceleration phases of each valve.
• control device is electrically connected to a voltage source for its supply voltage and current.
• this system comprises between the voltage source and the control device a voltage chopper device, configured to control the power supply and voltage of the control device.
• the voltage chopper device is produced by electronic switching components, the computer being further configured to control the state of these electronic switching components via pulse width modulated signals, these signals being supplied by the computer according to the identification of the acceleration and deceleration phases of each valve.
• the coil of an electromagnetic actuator is integral with the valve and the magnet is fixed relative to a cylinder head of the internal combustion engine.
• a motor vehicle comprising such an internal combustion engine.
• Figure 1 is a schematic view illustrating a vehicle (dashed) equipped with an internal combustion engine (solid line);
• Figure 2 is a graph illustrating the evolution of the position of a valve of the internal combustion engine during a lift cycle
• FIG. 3 is a schematic partial sectional view illustrating the engine, equipped with valves controlled by an actuating system
• FIGS. 4a, 4b, 4c are electrical representations of an electromagnetic actuator control device, and electrical current flow direction in this device, according to one embodiment
• FIGS. 5a, 5b and 5c are curves of energies and electric currents present in an electromagnetic actuator control device according to one embodiment;
• Figures 6a and 6b illustrate the flow direction of electric currents in an electromagnetic actuator control device according to one embodiment.
• Figure 1 is shown a vehicle 1 automobile - here a particular vehicle but it could be any other type of vehicle: utility, truck, construction equipment or helicopter.
• the vehicle 1 is equipped with an internal combustion engine 2 provided with cylinders 3 defining combustion chambers 4 and in which are slidably mounted pistons 5 linked, by connecting rods 6, to a crankshaft 7 whose rotation drives the wheels 8 of the vehicle 1 via a transmission (not shown).
• an internal combustion engine 2 provided with cylinders 3 defining combustion chambers 4 and in which are slidably mounted pistons 5 linked, by connecting rods 6, to a crankshaft 7 whose rotation drives the wheels 8 of the vehicle 1 via a transmission (not shown).
• FIG. 3 is a schematic partial sectional view.
• the engine 2 comprises, for each cylinder 3, at least one intake valve 9 and an exhaust valve 10.
• Each valve 9, 10 comprises a rod 11 which extends along a central axis X which defines an axial direction. At one end of the rod 11 is formed a head 12.
• Each valve 9, 10 is movable in translation relative to a cylinder head 13 of the engine 2 between a closed position in which the head 12 of the valve 9, 10 is supported against a seat 14 for closing an intake duct 15 (or, respectively, an exhaust duct 16) and an open position in which the head 12 is spaced from the seat 14 to put the cylinder 3 in communication with the duct 15 of admission (or, respectively, the exhaust duct 16).
• the engine 2 is of the diesel direct injection type and comprises, for this purpose, an injector 17 which opens directly into the combustion chamber 4, but it could be any other type of internal combustion engine: gasoline, indirect injection, hybrid.
• an actuating system 18 controls all of the valves 9, 10 of the internal combustion engine 2.
• This actuating system 18 comprises, for each valve 9, 10, an electromagnetic actuator 19 actuating the valve 9, 10 and a control device 20 controlling this actuator 19.
• the various control devices 20 associated with the valves 9, 10 of the motor 2 being themselves under control of a computer 21, also called engine control.
• a single control device 20 can control the electromagnetic actuators 19 associated, each, with a valve 9, 10.
• the computer 21 is connected to different sensors (not shown) which provide real-time data on the engine 2 and in particular on the position of the crankshaft 7 (via for example a position sensor) and the position of each valve 9, 10 with respect to the yoke 13 (for example via a dynamic valve lift sensor).
• the computer 21 independently controls each electromagnetic actuator 19 via the control device 20 with which it is associated in order to synchronize the valves 9, 10 with the other elements of the engine 2 such as the pistons 5 .
• Pistons 5 of an internal combustion engine 2 are generally out of phase with each other.
• an internal combustion engine 2 comprising four cylinders 3 may have two external pistons set at 180 ° with the two internal pistons, this setting making it possible to optimize the operation of the engine 2.
• the computer 21 makes it possible, in this case, thanks to feedback from the various sensors, to drive the electromagnetic actuators 19 via the control devices 20 in a time-shifted manner according to the architecture of the motor 2 chosen.
• each electromagnetic actuator 19 comprises at least one magnet 22 generating a magnetic field, and a coil 23 immersed in this field and electrically connected to the control device 20.
• the magnet 22 is integral with the valve 9,
• the coil 23 is integral with the valve 9, 10 and the magnet 22 is fixed relative to the cylinder head 13.
• the second embodiment is preferred, because it allows vis-à-vis the previous a better control of the displacement of each valve 9 10.
• a valve 9, 10 integral with a magnet 22 has a larger mass. The setting in motion of such a valve 9, 10 therefore requires a larger amount of energy and makes its braking more difficult, particularly at high engine speed, the inertial forces then being higher.
• the second embodiment is therefore considered in the remainder of this description. Nevertheless, the first embodiment is also applicable to the embodiments described below.
• each electromagnetic actuator 19 is immersed in a magnetic field, the presence of an electric current in this coil 23 then allows it to move it via a Laplace force and therefore to communicate a movement to each valve 9, 10. It is then possible to control the position of each valve 9, 10 in four time phases.
• FIG. 2 provides a better understanding of how such a control is performed.
• This figure illustrates the different positions P of a valve 9, 10 during the time T during a lifting cycle. It is assumed here, by convention, that the supply of the coil 23 with a positive current allows the displacement of the valve 9, 10 from a closed position PF to an open position PO, and vice versa, that the supply of the coil 23 with a negative current allows the displacement of the valve 9, 10 from the open position PO to the closed position PF.
• the positions PU and PI2 are intermediate positions between the closed position PF and the open position PO of the valve 9, 10. In the course of a valve lift cycle 9, the following four phases are distinguished:
• a first phase PH1 during which the coil 23 of the electromagnetic actuator 19 is supplied with a positive current, to provide an acceleration to the valve 9, 10 from the closed position PF to an intermediate position PU towards the open position PO ;
• a second phase PH2 during which the power supply of the coil 23 is cut off, starting from the intermediate position PU, to generate a negative current resulting from the inertia stored by the valve 9, 10, this negative current for decelerating the valve 9, 10 to the open position PO;
• a third phase PH3 during which the coil 23 of the actuator is supplied with a negative current, to provide an acceleration to the valve 9, 10 from the open position PO to an intermediate position PI2 towards the closed position PF;
• a fourth phase PH4 in which the power supply of the coil 23, from the intermediate position PI2, is cut to generate a positive current from the inertia stored by the valve 23, this positive current for decelerating the valve 9 , 10 to the open position PF.
• the acceleration of the valve 9, 10 during the first phase PH1 and the third phase PH3 is made possible by the creation of a force according to the Laplace principle.
• the deceleration of the valve 9, 10 during the second phase PH2 and the fourth phase PH4 results in turn from the Lenz-Faraday principle: after its acceleration, the coil 23 is made mobile in the magnetic field under the effect of the forces of 'inertia. It then appears in accordance with this principle, an electromotive force across the coil 23. This electromotive force then induces in the coil 23 the flow of a current opposite to that of the acceleration. The appearance of such a current then generates a Laplace force opposing the inertial movement of the coil 23, causing its deceleration and thus the deceleration of the valve 9, 10 actuated by the electromagnetic actuator 19.
• the electric current for accelerating the valve 9, 10 during the first phase PH1 and the third phase PH3, is provided by the control device 20 associated with each electromagnetic actuator 19.
• this control device 20 can, if necessary, provide a reverse current to the current allowing the acceleration of the valve 9, 10 to facilitate its deceleration.
• control device 20 associated with each electromagnetic actuator 19 is designed to have at least two configurations: an active configuration in which the control device supplies the coil 23 of the electromagnetic actuator electrically via a current to provide an acceleration (and possibly deceleration) phase for the valve 9, 10;
• FIG. 4a illustrates an embodiment of a control device 20 electrically connected to the coil 23 of an electromagnetic actuator 19 according to one embodiment.
• the coil 23 of the electromagnetic actuator 19 is modeled by an inductance Lbob, a function of the number of turns of this coil 23, and an internal resistance Rint.
• the electromotive force induced by this coil 23 during the acceleration and deceleration phases of the valve 9, 10 is symbolized here by the voltage generator Vbob.
• the dashed rectangles delimit the coil 23 of the electromagnetic actuator 19 and the control device 20.
• control device 20 comprises an H-bridge structure, connected to the terminals of the coil 23 of the electromagnetic actuator 19, the H-bridge being configured to control the flow direction of the currents. electric through this coil 23.
• the H bridge is made from four switching electronic components T1, T2, T3, T4.
• the electronic switching components are field effect transistors with metal-oxide-semiconductor structure MOSFET.
• any other type of transistor, and more generally, any other electronic switching component T1, T2, T3, T4 can be used: for example bipolar transistors, JFET type transistors, relays or switches.
• the manner in which the electronic switching components T1, T2, T3, T4 constituting the H-bridge are connected to the coil 23 is thus given by way of purely illustrative example.
• the states of the electronic switching components T1, T2, T3, T4 of the H bridge are controlled by pulse width modulated signals PWM (acronym for "Pulse Width Modulation") provided by the computer 21 of the vehicle 1.
• PWM pulse width modulated signals
• the transistors T1 and T4 are connected by their gate to be controlled by the same PWM2 signal (respectively PWM1).
• the signals PWM1 and PWM2 are pulse width modulated signals controlled by the computer 21 of the vehicle 1.
• each transistor T1, T2, T3, T4 is controlled individually via its gate, by a modulated pulse width signal from the computer 21.
• each transistor T1, T2, T3, T4 further comprises, respectively at its terminals a diode D1, D2, D3, D4 connected in parallel and in reverse.
• each of these diodes D1, D2, D3, D4 acts as a non-return diode, making it possible to protect the transistor T1, T2, T3, T4 from the inverse currents in the forward direction of these transistors, these inverse currents being from the coil 23 of the electromagnetic actuator 19 during the deceleration phases of the valve 9, 10.
• the control device 20 is electrically connected to a source for its supply of current and voltage.
• the H-bridge is electrically powered in voltage with respect to a ground GND, and in current, by the battery of the vehicle 1, symbolized here by the voltage generator Vbat.
• a filter can be made between the battery and the H-bridge, so as to filter the resonant frequencies in the control device, these frequencies being likely to appear for high engine speeds.
• An example of an LC type filter is illustrated in FIG. 4a, this filter being made by an inductance L arranged in series after the voltage source Vbat and a capacitor C arranged in parallel between the input of the H bridge and the GND mass. .
• a voltage chopper device is formed at the output of the battery, so as to control the voltage resulting from the latter as required.
• Such a device is produced using electronic switching components T5, T6.
• This device therefore makes it possible to connect or disconnect the power supply supplied by the battery to the H-bridge, and thus to control the possible power supply of the coil of the electromagnetic actuator 19, allowing the acceleration of the valve 9,
• these electronic switching components T5, T6 are also controlled simultaneously or individually by a pulse width modulated signal from the computer 21.
• transistor T6 MOSFET connected between the inductance L and the capacitance C
• transistor T7 MOSFET connected between the inductor L and the ground GND
• the transistors T6, T7 being respectively controlled by a signal PWM3, PWM4 applied on their grid via the computer 21 of the vehicle 1.
• control device 20 allows via a suitable control states of the switching electronic components T1, T2, T3, T4, T5, T6 by the computer 21, the management of the acceleration phases. (phase PH1 or PH3) or deceleration (phase PH2 or PH4) of a first valve 9, 10.
• Figures 4b and 4c illustrate flow directions of electric currents in a control device 20 similar to that of Figure 4a.
• an acceleration phase relating to
• the phase PH1 is obtained via the control of the signals PWM1, PWM2, PWM3, PWM4 by the computer, so as to render the transistors T2, T3, T5, T6 in an on state (ie conductors) and the transistors T1 , T4 in an open state (i.e., locked).
• Such a configuration then allows the circulation of a positive current il in the coil thus allowing the acceleration of the valve 9, 10 in a first direction.
• the circulation of the current is here symbolized in Figure 4b, in the form of dotted arrows;
• phase PH2 is obtained by controlling the signals PWM1, PWM2, PWM3, PWM4 by the computer, so as to render transistors T1, T4, T5, T6 in an on state and transistors T2, T3 in an open state.
• Such a configuration then allows the circulation of a negative current i2 in the coil thus allowing the acceleration of the valve 9, 10 in a second direction.
• the circulation of the current i2 is here symbolized in FIG. 4c,
• the control device 20 described above further comprises an interconnection with at least one second electromagnetic actuator control device 19 for a second valve 9, 10.
• a second control device can be similarly realized. or differently from the control device described above.
• FIGS. 4a, 4b, 4c such an interconnection to a second control device is symbolized via the conductive wires 24, 25 shown in dotted lines.
• control device is configured to
• control devices similar to that described above are interconnected. According to one embodiment, these devices can then transmit during a deceleration phase of their valves 9, 10, the electrical energy induced by the coils 23 of their respective electromagnetic actuators 19, towards the same coil of another electromagnetic actuator 19. associated with a valve 9, 10 in the deceleration phase. According to another embodiment, a control device 20 sends the electrical energy induced by the coil 23 of its respective electromagnetic actuator 19 via the interconnection to a plurality of coils 23 electromagnetic actuators 19 including their respective valve 9, 10 in the deceleration phase.
• control of the acceleration and deceleration phases of a valve 9, 10 as well as the use of the interconnection of the control device 20 are controlled by the computer 21 of the vehicle 1, via the control of the states of the switching electronic components T1, T2, T3, T4, T5, T6.
• the control of the state of the switching electronic components T1, T2, T3, T4, T5, T6 is determined by the computer 21 as a function of the phase in which each valve 9, 10 is located.
• the acceleration and deceleration phases of each valve 9, 10 are determined from information returned to the computer 21 by sensors determining the position of each valve 9, 10 relative to the cylinder head.
• these phases are determined by the computer 21 as a function of the angular position of the crankshaft 7.
• one or more voltage sensors and / or current sensors are further arranged in the 20 control device and their measurements to the computer 21, so that it determines the acceleration or deceleration phases of each valve 9, 10. These phases are, by way of examples, determined in comparison with modelizations theoretical or sets of measurements prerecorded in the calculator 21.
• curve 5a illustrates the Joule variation (J) of the kinetic energy (ordinate) present in the control device, resulting from the movement of the valve 9, 10, as a function of the angular position in degree of the crankshaft. 7 (as abscissa);
• curve 5b illustrates the variation in Joule (J) of the inductive energy (ordinate), that is to say the energy stored by the coil of the electromagnetic actuator 19, as a function of the angular position in degrees crankshaft 7 (as abscissa);
• curve 5c illustrates the electric current (A) in amperes (ordinate) flowing in the coil of the electromagnetic actuator 19, as a function of the angular position in degree of the crankshaft 7 (in the abscissa).
• phase i and ii correspond to deceleration phases of the valve 9, 10. More specifically, the phase i corresponds to a deceleration phase of the valve 9, 10 before its maximum lifting in an open position PO, while the phase ii corresponds to a deceleration phase of the valve 9, 10 before its docking against the seat 14 in the closed position PF. As stated previously, during these phases an electromotive force appears at the terminals of the coil 23 of the actuator
• phase iii corresponds to an acceleration phase of the valve 9, 10 during the first phase
• the iv and v phases correspond to a deceleration phase of the valve 9, 10 before its docking against the seat 14 in a closed position PF.
• the inductive energy peaks observed, are explained by the large variations in the electric current flowing through the coil 23 of the electromagnetic actuator 19, here between -50 and 80 amperes. These currents variations then allow storage in electromagnetic form of an inductive energy in the coil 23 of the electromagnetic actuator 19.
• the battery (voltage source Vbat) does not electrically supply the control device 20 during the deceleration phases. coil 23 to which is connected this device thus becomes for it a source of electrical power in voltage and current.
• a suitable control by the computer 21 of the electronic switching components T1, T2, T3, T4, T5, T6 during the phases iii, iv, v then makes it possible to recover this energy and to transmit it via the interconnection to another valve 9 , 10 in the acceleration phase.
• the computer 1 is then able to identify each of the phases i, ii, iii, iv, v depending on the angular position of the crankshaft 7, 1 information concerning this position being raised by a sensor to the computer 1.
• the computer 1 is therefore capable as a function of information raised by sensors (eg crankshaft angle 7, position of the valves 9, 10).
• the switching electronic components T1, T2, T3, T4, T5, T6 can be controlled in order to recover the kinetic or inductive energy associated with these phases and to send these energies to at least one other valve 9, 10 identified as being in an acceleration phase.
• Figures 6a and 6b show the notations introduced for Figures 4a, 4b, 4c.
• the computer 21 identifies a phase i, ii, iii, iv, v for a valve 9, 10 with respect to the angular position of the crankshaft 7 and switches the electronic switching components T1, T2, T3 , T4, T5, T6 as follows:
• the computer controls the signals PWM1, PWM2, PWM3, PWM4 so as to render the transistors T2, T3 in an on state and the transistors T1, T4, T5, T6 in one open state.
• the dashed arrows illustrate the flow direction of the electric currents relating to the phases i or iii.
• the currents circulating during the phases i, iii are respectively symbolized by the dotted arrows iph1, iph3, above the voltage source Vbob modeling the induced electromotive force and inductance Lbob modeling the coil 23 of the electromagnetic actuator 19.
• such a command therefore makes it possible to recover the kinetic / inductive energy of the phases i / iii via the currents iph1 / iph3, and their transmission to another valve 9, identified by the computer 21 as being in the acceleration phase. ;
• the computer 21 controls the signals PWM1, PWM2, PWM3, PWM4 so as to render the transistors T1, T4 in an on state and the transistors T1, T4, T5 , T6 in an open state.
• the dashed arrows illustrate the flow direction of the electric currents relating to the phases ii, iv or v.
• the currents flowing during the phases ii, iv, v are respectively symbolized by the dotted arrows iph2, iph4, iph5 above the voltage source Vbob and the inductance Lbob.
• such a command therefore makes it possible to recover the kinetic / inductive energy of the phases ii / iv, v via the currents iph2 / iph3, iph4, iph5 and their transmission to another valve 9, identified by the computer 1 as being in the acceleration phase.
• control device 20 is designed to adapt to the different speeds of rotation of the motor 2.
• Various curves making it possible to identify the variations of the kinetic energy and of the inductive energy in this device can therefore be determined according to different engine speeds.
• These energy variation curves are, by way of example, simulated or measured according to data such as the crankshaft angle 7 and / or voltages / currents present in the control device, for a fixed engine speed. .
• the values associated with these curves can then be recorded in the computer 21 so that it can determine the deceleration periods allowing the recovery and the sending of kinetic energy and / or inductive, to the coil 23 of the electromagnetic actuator 19 of another valve 9, 10 in the acceleration phase.
• the electrical currents through the coil 23 are high: of the order of ten amperes.
• the inductive energy induced in the control device 20 then makes it possible to provide voltages much higher than the voltage of the battery.
• Such a control device 20 therefore makes it possible to increase the power. It is thus possible to transmit the electrical energy present in the control device 20 to one or more valves 9, 10 in acceleration phases, thus facilitating their actuation. This also makes it possible to increase the electric current more quickly in the valve actuating system 18, 9 and thus to improve the reactivity time of this system. It is thus possible to reduce the power consumption for the actuation of these valves 9, 10 and thus reduce the power consumption in the actuating system 18, this reduction being of the order of 40% compared to existing systems .
• valve 9, 10 in the deceleration phase, the fact of transferring its kinetic energy, allows better control of its braking. This also makes it possible to ensure that the docking of the valve 9, against the seat 14 when it is closed, takes place with a kinetic energy that is almost zero.
• the valve 9, 10 thus impacts the seat 9, 10, with a very low speed compared to the usual distribution systems: for a revolutions of 6000 revolutions per minute we obtain a speed of 0.1m / s to 0.1mm of the docking, while a mechanical system has a speed of 1 m / s at the same distance. This allows an acoustic point of view a control of its noise unlike existing systems.
• the system 18 for actuating valves 9, 10, via its control device 20, allows a better control of the overall control of the valves 9, 10 vis-à-vis the existing models.
• the proposed control device 20 directly transfers the energy recovered during the deceleration phases of each valve 9, 10. Compared to control devices storing the recovered energy, the control device 20 has the advantages of reduce losses by Joule effect, and thus reduce the average temperature of the actuator 19 electromagnetic. This therefore allows an increase in the life of this type of device.
• such a valve actuating system 18, 10 has the advantage of adaptability to the different speeds of rotation of the engine 2, unlike systems using mechanical control devices.

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