Abstract: A device for radiofrequency ignition of an internal combustion engine, including a power supply circuit including a transformer with a secondary winding connected to at least one resonator that has a resonant frequency in excess of 1 MHz and including two electrodes configured to generate a spark to initiate combustion of a combustible mixture in a cylinder of the engine in response to an ignition command. A measuring capacitor is connected in series between the secondary winding and the resonator, a measurement circuit measures a current at terminals of the measuring capacitor, the current providing an electrical image of how combustion is progressing, and a protection circuit is connected between the capacitor and the measurement circuit and is configured to spare the current measurement acquisition time from electrical effects caused by the ignition command.

Abstract: An injection device for injecting pressurized fluid includes a housing, an actuator, and an energizing unit. The housing includes at least one axial cavity filled with pressurized fluid. The actuator includes a stack with a first transverse face extended axially by a penetrating member and a second transverse face axially opposite the first. The stack includes at least one electroactive part including an electroactive material. The member includes a piston engaged in the cavity and forming a fluidic connection between the actuator and the housing. The energizing unit sets the electroactive part of the actuator in vibration with a set period ?. The penetrating member includes an axial length such that the propagation time T of the acoustic waves produced by the vibrations of the electroactive part of the actuator and traveling along this length satisfies the following equation: T=[2n+1]*[?/4], where n is a positive integer coefficient.

Abstract: A device for controlling a power supply of a radio frequency ignition of a combustion engine, including: an interface that receives measurement signals of operating parameters of a combustion engine; an interface that outputs a control signal; a module that stores relationships between measurement signals and the frequency of a control signal to be generated; a module that determines the frequency of a control signal to be generated on the basis of measurement signals received on the reception interface and of the relationships stored; and a module that applies the control signal at the determined frequency.

Abstract: A radiofrequency plasma generating device, including: a control module generating a control signal at a control frequency, a power supply circuit including a breaker switch controlled by the control signal, the breaker switch applying an excitation signal to an output of the power supply circuit at the control frequency defined by the control signal, a resonator exhibiting a resonant frequency of greater than 1 MHz, connected to the output of the power supply circuit and adapted to generate a voltage for making a spark when it is excited by the excitation signal, and a mechanism monitoring the control module and configured to modify the frequency of the resonator excitation signal in a manner synchronous with the control signal, during application of the excitation signal.

Abstract: An internal combustion engine radio frequency spark plug including two plasma-generating electrodes, separated by an insulator, that constitute respectively an outer shell enclosing the insulator and a central electrode housed in a central bore of the insulator. The spark plug includes a deep opening over the entire circumference of the shell, forming a heat-exchanger chamber inside the spark plug shell, opening outwards.

Abstract: A generator of a pseudoperiodic logic signal of mean period Tmean includes: a reference clock of period Tref, a logic memory, changing state on receipt of a pulse, a first mechanism producing a normal pulse on completion of a base time interval Tsec=K×T ref, with K an integer, a second mechanism producing a shifted pulse on completion of a modified time interval T?sec=(K±1)×Tref, and a selector capable of selecting the mechanism that produces the pulse, in such a way as to regularly include a shifted pulse so as to correct the mean period, to generate a pseudoperiodic signal. Such a generator may find application, as an example, to driving a resonator for producing a plasma spark for radiofrequency ignition.

Abstract: A radio frequency plasma generator power supply, including: an interface that receives a request to determine an optimal control frequency; an output interface configured to be connected to a plasma generation resonator; a power supply module configured to apply a voltage at a set point frequency to the output interface, the voltage, depending on its frequency, selectively unable to allow generation of plasma of the resonator on receipt of a request during a phase optimizing power supply frequency of the generator and able to allow generation of plasma of the resonator during an operating phase; an interface that receives an electrical measurement of power supply of the resonator; a module that determines optimal control frequency, successively provides various set point frequencies to the power supply module on receipt of a request, and determines an optimal control frequency depending on electrical measurements received by the reception interface.

Abstract: An internal combustion engine radio frequency spark plug including two plasma-generating electrodes, separated by an insulator, that constitute respectively an outer shell enclosing the insulator and a central electrode housed in a central bore of the insulator. The spark plug includes a deep opening over the entire circumference of the shell, forming a heat-exchanger chamber inside the spark plug shell, opening outwards.

Abstract: An injector including a nozzle that includes an opening and a seat, a needle movably mounted in the nozzle and having an end defining a valve in a contact area with the seat, a mechanism for vibrating the valve, a first acoustic-impedance breaking area at a first distance from the valve along the nozzle, and another first acoustic-impedance breaking area at a second distance from the valve along the needle. Each of the first and second distances is such that the respective propagation time of acoustic waves along the distance is: Ti=ni*[?/2], where ni is a positive integer coefficient different from zero with i=3 for the first distance and i=4 for the second distance, ? being a period of the vibrations.

Abstract: A plasma generating device including: a supply circuit including a switch controlled by a control signal for applying an intermediate voltage on an output of the control circuit at a frequency defined by the control signal; a plurality of plasma-generating plug coils arranged in parallel on the output via connectors, each connector being adapted to be removably connected to a corresponding plug coil and including a mechanism adapted to offset the resonance frequency of the plug coil so that each plug coil has a distinct resonance frequency; a control device of the supply circuit, that determines the control frequency from the resonance frequencies of the plug coils to selectively control the plug coils according to the control frequency used.

Abstract: The invention relates to an injector including a needle mounted in a nozzle and having an end defining a valve, the needle being connected at the other end to an actuator including first, second and third portions, the first and third portions being provided on either side of the second portion, the three portions being tightened together in order to form a block having two axially opposite limits, the first portion being connected with the needle at one of said limits, and an excitation means for vibrating the second portion according to setpoint period ?. According to the invention, the length between the two limits of the block is such that the propagation time T of the acoustic waves generated by the vibrations of the second portion of the actuator and running along that length meets the equation: T=n*[?/2], where n is an integer positive multiplication coefficient different from zero.

Abstract: The invention relates to a plasma-generating spark plug which undergoes excitation in the radio frequency domain. The invention comprises at least one first metallic electrode (12, 14), an insulator (13), one of which is equipped with a housing (130) in which the other element (13, 14) is mounted with a gap (15, 16) therebetween. The surface of the insulator (13) opposite the first electrode (12, 14) is metalized.

Abstract: A radiofrequency ignition device for an internal combustion engine, including: a supply circuit, including a transformer, a secondary winding of which is connected to a resonator including two electrodes configured to generate a spark so as to initiate combustion in a cylinder of the engine upon an ignition command, a measurement capacitor, connected in series between the secondary winding of the transformer and the resonator, and a measurement circuit measuring ionization current of the combustion gases, connected to the measurement capacitor and including a voltage generator with low input impedance, to provide a polarization voltage of the measurement capacitor so as to generate the ionization current, a first amplifier amplifying the ionization current and a measuring mechanism measuring a voltage representative of the amplified ionization current and connected at an output of the first amplifier.

Abstract: A method for controlling a radio-frequency plasma generator including a supply circuit with a switch controlled by at least one control pulse train, for applying an intermediate voltage at a control frequency on an output to which is connected a resonator for generating a spark between two electrodes when a high voltage level is applied to the output. The method receives first and second measurement signals respectively representative of the operation of a combustion engine and of the type of spark generated; and real-time adjusts, based on the received measurement signals, at least one parameter selected from at least the intermediate voltage level, the control frequency, and the duration of the control train, to promote branching of the spark generated.

Abstract: A measuring device including: a supply circuit for radiofrequency ignition including a transformer including a secondary winding connected to at least one resonator having a resonance frequency higher than 1 MHz, and including two electrodes capable of generating a spark upon an ignition control; a measuring capacitor connected in series between the secondary winding and the resonator; a measuring circuit of ionization current of the combustion gases in a cylinder of the internal combustion engine associated with the resonator, the circuit being connected at terminals of the measuring capacitor; and/or a measuring circuit that measures a voltage at the resonator terminals upon an ignition control, the circuit being connected to terminals of the measuring capacitor.

Abstract: A fuel injecting device and method of controlling the fuel injection device. The fuel injection device includes a cylindrical body, a needle whose end includes with a head forming a valve on a seat supported by the end of the cylindrical body, an actuator made of an electroactive material, including a rod and that displaces the head such that the valve is opened, and a prestressing device holding the needle and a counterweight such that they are pressed against the rod opposite end. The needle extends coaxially to the cylindrical body in a form of a rigid bar and axially resonates when exposed to axial pulses at a determined excitation frequency by the actuator.

Abstract: An internal combustion engine including: a pulse current generator; at least one electrode including at least one tip; a mechanism controlling the electrical supply to the electrode by the generator; and a combustion chamber in which the tip of the electrode is positioned, the tip being separated from the inner wall of the chamber by a minimum separation distance. The current generator and the electrode are configured such that the power density generated while the electrode is being supplied is less than 105 watts per cubic centimeter, this power density being equal to the electrical supply power of the electrode divided by the minimum separation distance cubed.

Abstract: An essentially-elongated spark plug for an internal combustion engine of a motor vehicle, including: an essentially-capacitive lower part including two coaxial electrodes; an essentially-inductive upper part including a central mandrel, a coaxial winding around the mandrel, and an external tubular casing that serves as electromagnetic armor; and an insulant disposed radially between the casing and the winding. The essentially-inductive upper part includes a second internal casing of electromagnetic armor, which is disposed radially between the insulant and the external casing.

Abstract: A control device including: an input terminal for receiving a logic control signal; an output terminal for delivering an output control signal from the high-voltage MOS transistor; a first NMOS control transistor with low internal impedance, which is connected between ground and the output terminal and the gate of which is connected to the input terminal; and a second PMOS control transistor, which is connected between a supply terminal and the output terminal and the gate of which is connected to the input terminal by a bipolar transistor mounted to a common base, and which is current controlled at the emitter thereof by a capacitive connecting circuit.

Abstract: A device including two plasma generation electrodes, a series resonator having a resonant frequency above 1 MHz and including a capacitor with two terminals, and an induction coil surrounded by a screen, the capacitor and the coil being placed in series, the electrodes being connected to the respective terminals of the capacitor. The ratio of the spark plug to the radius of the screen is equal to 0.56. The device can optimize the Q-factor of such a device by adjusting the radius of the coil to that of the screen.