EP2732149B1 - Laser spark plug and cleaning method for same - Google Patents

Laser spark plug and cleaning method for same Download PDF

Info

Publication number
EP2732149B1
EP2732149B1 EP12724610.6A EP12724610A EP2732149B1 EP 2732149 B1 EP2732149 B1 EP 2732149B1 EP 12724610 A EP12724610 A EP 12724610A EP 2732149 B1 EP2732149 B1 EP 2732149B1
Authority
EP
European Patent Office
Prior art keywords
spark plug
laser spark
region
channel
laser
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Not-in-force
Application number
EP12724610.6A
Other languages
German (de)
French (fr)
Other versions
EP2732149A1 (en
Inventor
Martin Weinrotter
Pascal Woerner
Joerg Engelhardt
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP2732149A1 publication Critical patent/EP2732149A1/en
Application granted granted Critical
Publication of EP2732149B1 publication Critical patent/EP2732149B1/en
Not-in-force legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
    • F02P23/00—Other ignition
    • F02P23/04—Other physical ignition means, e.g. using laser rays
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B5/00—Engines characterised by positive ignition
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
    • F02P13/00—Sparking plugs structurally combined with other parts of internal-combustion engines
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49229—Prime mover or fluid pump making

Definitions

  • the invention relates to a laser spark plug, in particular for an internal combustion engine, having a combustion chamber window through which laser radiation can be emitted from an interior of the laser spark plug into an external space, wherein the laser spark plug has a component which at least partially surrounds the beam path of the laser radiation in the region of the exterior space.
  • Such a laser spark plug is for example from the EP 2 072 803 A1 known.
  • the invention further relates to a cleaning method for such a laser spark plug.
  • the laser spark plug in the region of the component has at least one channel having at least two opening portions and a fluid communication between the opening portions allows a first opening portion in the region of an outer surface of the combustion chamber window and a second
  • Opening portion in a radially outer region of the laser spark plug, in particular the component is arranged.
  • the channel according to the invention particularly advantageously enables an efficient loading of the outer surface of the combustion chamber window with a fluid, for example a cleaning solution or the like.
  • a fluid for example a cleaning solution or the like.
  • the channel according to the invention advantageously also allows targeted introduction of the cleaning fluid into the region of the laser spark plug to be cleaned.
  • a longitudinal axis of at least one first longitudinal section of the channel arranged in the region of the first opening section essentially points to a radially inner region of an outer surface of the combustion chamber window, whereby a selective introduction is effected regardless of a spatial arrangement of the second opening section of the channel a cleaning fluid to the optically active region of the combustion chamber window is made possible.
  • a flow direction of a cleaning fluid introduced through the channel can advantageously be determined or influenced by the longitudinal axis of the first longitudinal section, in particular its orientation.
  • the longitudinal axis of the first longitudinal section is aligned such that an intersection of the longitudinal axis with the outer surface of the combustion chamber window is at a distance from the optical axis of the laser spark plug, which is at least approximately 20% of a radiation cross section of the laser radiation in the region the outer surface is preferably at least about 40%.
  • a particularly efficient cleaning of the outer surface of the combustion chamber window is made possible in that surface region through which laser radiation provided by the laser spark plug passes into the outer space.
  • At least a second longitudinal section of the channel has a diameter of 0.5 mm to about 4.0 mm, in particular from about 1.0 mm to about 2.0 mm.
  • This configuration of the channel allows optimal loading of the Combustion chamber window with pressurized cleaning fluid, wherein the cleaning fluid in particular with a comparatively high pulse (high pressure, high speed) is radiated to the combustion chamber window and thus cleans this.
  • the channel according to the invention can advantageously also be used for wetting with cleaning fluid which, for example, has a relatively low pressure.
  • a mechanical cleaning for example with a brush or a cotton swab or the like through the channel can be performed.
  • a first longitudinal section of the channel arranged in the region of the first opening section has a diameter of approximately 0.1 mm to approximately 2.0 mm, in particular from approximately 0.2 mm to approximately 1.0 mm ,
  • the channel according to the invention has different length sections, each with different cross-sectional openings or diameters, a nozzle effect can advantageously be achieved for a cleaning fluid flowing through the channel, whereby the momentum of the detergent flow directed onto the combustion chamber window can be advantageously influenced.
  • the channel is designed so that it can be temporarily locked so that no fluid communication between the first and the second opening portion is possible.
  • the channel advantageously has, at least in sections, an internal thread into which a grub screw can be screwed.
  • the channel can be formed at least in sections as a stepped bore, so that a particularly cost-effective production of the laser spark plug according to the invention is possible.
  • the channel according to the invention may also have a more complex geometry.
  • the channel does not necessarily have a substantially cylindrical shape but may for example also have one or more curved lengths, whereby a directional deflection of the cleaning fluid is possible.
  • the laser spark plug in a radially outer region fastening means for mechanical connection with a target system, namely an external thread, for example for screwing into a corresponding internal thread of a cylinder head of an internal combustion engine.
  • the second opening section lies in the region of the fastening means. It follows in particular that the second opening section is closed in an installed position of the laser spark plug in the target system. This advantageously ensures that the radially arranged on the outside of the laser spark plug second opening portion in the installed position of the laser spark plug has no direct connection to a combustion chamber of the internal combustion engine, in which the laser spark plug protrudes in its installed position.
  • the component which at least partially surrounds the beam path of the laser radiation in the region of the outer space can be formed, for example, as a diaphragm and / or as an antechamber.
  • the component in question complicates the accessibility to the outer surface of the combustion chamber window, so that the cleaning of the combustion chamber window using the channel according to the invention is particularly useful.
  • the channel can be at least partially integrated in the diaphragm or an antechamber wall.
  • FIG. 1 schematically shows a laser-based ignition system of an internal combustion engine, in which a laser spark plug 100 is arranged in the region of a cylinder head of the internal combustion engine, that a combustion chamber facing end portion of the laser spark plug 100 protrudes in a conventional manner into the combustion chamber 200 of the internal combustion engine.
  • the laser spark plug 100 is supplied with optical radiation via pumping radiation 22, which is provided by a pumping light source 20.
  • the laser spark plug 100 can, for example, have an integrated, passively Q-switched solid-state laser 102, which generates high-energy laser ignition pulses in a manner known per se when exposed to the pump light of the pump light source 20.
  • a focusing optics 104 for focusing the generated laser radiation onto an ignition point ZP located in the pre-chamber 120a.
  • the ignition point ZP directly in the combustion chamber.
  • an interior of the laser spark plug 100 is delimited by a combustion chamber window 106 toward the prechamber 120a, through which the laser radiation L is transmitted.
  • FIG. 2 shows a detail view of a combustion chamber-facing end portion of a laser spark plug according to an embodiment of the present invention.
  • the laser spark plug has similar to the schematic illustration according to FIG. 1 via an antechamber 120a into which laser radiation L for igniting an air / fuel mixture located in the prechamber 120a can be injected through the combustion chamber window 106.
  • the laser spark plug according to FIG. 2 an aperture 120b, also referred to as a "light path" element.
  • the diaphragm 120b by virtue of its presently approximately frusto-conical opening, on the one hand enables the prechamber 120a to be exposed to laser radiation L from the in FIG. 2
  • protection of the outer surface 106a of the combustion chamber window 106 from dirt particles from the antechamber 120a is provided because the aperture 120b shields the outer surface 106a of the combustion chamber window 106 at least in certain areas.
  • the pre-chamber 120a of in FIG. 2 The illustrated laser spark plug also has so-called transfer ports 120a 'which provide fluid communication between the pre-chamber 120a and the surrounding space 200, for example, the combustion chamber 200 of the internal combustion engine, allow.
  • the combustion chamber window 106 in particular the outer surface 106a, can only be cleaned by introducing a cleaning fluid through the overflow channels 120a 'into the interior of the prechamber 120a and through the opening of the aperture 120b onto the outer surface 106a of the Combustion window 106 occurs.
  • the cleaning of conventional laser spark plugs with prechamber or diaphragm is complex and has only a relatively small effect.
  • the laser spark plug has at least one channel 122 which has at least two opening sections 122a, 122b and permits fluid communication between the opening sections 122a, 122b.
  • a first opening section 122a of the channel 122 is arranged in the region of the outer surface 106a of the combustion chamber window 106, and a second opening section 122b of the channel 122 is located in a radially outer region of the laser spark plug 100, in particular the aperture 120b or the pre-chamber 120a , is arranged.
  • a cleaning fluid to be introduced into the channel 122 from the outside, which is conducted through the channel 122 directly to the surface area 106a of the combustion chamber window 106 to be cleaned.
  • a fluid transport of cleaning fluid from the outer space 200 or the radially outer region of the pre-chamber 120a through the channel 122 to the outer surface 106a of the combustion chamber window 106 takes place.
  • Cleaning fluid rebounding from the outer surface 106a can advantageously leave the laser spark plug or the prechamber 120a through the overflow passages 120a '.
  • At least two channels 122 according to the invention are provided, wherein at least one first channel 122 can be used to supply cleaning fluid to the combustion chamber window 106, while at least one further channel (not shown) thereto is used to remove the supplied cleaning fluid from the region of the prechamber 120 a in the outer space 200.
  • the channel 122 according to the invention may also have more than two opening portions and thus, for example, a Y-shaped branch (not shown) and the like, wherein at least two opening portions 122a, 122b are arranged as described above, for easy cleaning of the combustion chamber window 106 from outside the To enable laser spark plug 100.
  • a longitudinal axis of at least one arranged in the region of the first opening portion 122 a first length portion LA1 of the channel 122 substantially to a radially inner region B1 of the outer surface 106a of the combustion chamber window 106 indicates, so that an efficient loading of the combustion chamber window 106 with the cleaning fluid is possible.
  • the longitudinal axis of the first longitudinal section LA1 is aligned so that an intersection of the longitudinal axis with the outer surface 106a of the combustion chamber window 106 is a distance Y (FIG. FIG. 2 ) to the optical axis OA of the laser spark plug 100, which is at least about 20% of a beam cross section of the laser radiation L in the region of the outer surface 106a, preferably at least about 40%.
  • This essentially off-centering of the combustion chamber window 106 results in a particularly good cleaning effect.
  • At least a second length section LA2 of the channel 122 has a diameter Z2 of about 0.5 mm to about 4.0 mm, in particular from about 1.0 mm to about 2.0 mm.
  • the longitudinal section LA1 of the channel 122 arranged in the region of the first opening section 122a has a diameter Z1 of approximately 0.1 mm to approximately 2.0 mm, in particular from approximately 0.2 mm to approximately 1.0 mm, has.
  • FIG. 3 shows a further embodiment of the laser spark plug according to the invention, in which the laser spark plug is not provided with an antechamber 120a (FIG. FIG. 2 ), but only with an aperture 120b is equipped. Also in this variant of the invention, at least one channel 122 may be provided for impinging the outer surface 106a of the combustion chamber window 106 with cleaning fluid. How out FIG. 3 As can be seen, the diaphragm 120b may also be formed integrally with the housing 100 'of the laser spark plug.
  • FIG. 4 shows a laser spark plug 100 according to the invention with the channel 122 according to the invention, which is also referred to as flushing channel due to its suitability for cleaning the laser spark plug 100 and its combustion chamber window 106, and one around the combustion chamber facing end portion of the laser spark plug 100 arranged cleaning device 300.
  • the cleaning device 300 has an inflow Z for supplying cleaning fluid, which is passed via the inlet Z in an annular groove R.
  • the cleaning device 300 is mechanically connectable to the laser spark plug 100 such that fluid communication can also be established between the annular groove R and the flushing channel 122 according to the invention, cf. FIG. 4 , As a result, the cleaning fluid supplied to the cleaning device 300 can pass from the inflow Z via the annular groove R into the flushing channel 122 and thus onto the outer surface of the combustion chamber window 106.
  • a return flow of the cleaning fluid applied to the combustion chamber window 106 may occur at the in FIG. 4 imaged configuration through the overflow channels of the pre-chamber to the outflow A of the cleaning device 300 done.
  • the fluid used can be filtered, pressurized again and fed back to the inlet Z, so that advantageously results in a cycle for the cleaning fluid.
  • the cleaning device 300 may advantageously also comprise means for temperature control, in particular heating, of the cleaning fluid, as a result of which a cleaning time can be shortened.
  • the heating may advantageously be configured so that the cleaning fluid is not heated to its boiling point or even to a maximum of a predeterminable limit of about 50 ° C in order to avoid burns when handling the device 300.
  • FIG. 5 As already mentioned, a detailed view of a combustion chamber-facing end region of a laser spark plug 100 according to the invention is shown.
  • a first longitudinal section LA1 of the channel 122 according to the invention is as shown FIG. 5 can be seen aligned so that it is substantially on a radially inner, central region of the outer surface 106a of the combustion chamber window 106, whereby a precise loading of the optically active outer surface of the combustion chamber window 106 is possible with the cleaning fluid.
  • first longitudinal section LA1 has a smaller diameter than at least one further second longitudinal section LA2 adjoining it in the axial direction of the channel 122, a nozzle effect for fluid flowing through the channel 122 can be effected in a manner known per se, so that a speed of the can be influenced on the combustion chamber window 106 incoming cleaning fluid.
  • first longitudinal section LA1 has a first diameter Z1
  • second longitudinal section LA2 has a second diameter Z2> Z1.
  • FIG. 5 illustrated configuration of the channel 122 can be advantageously carried out as a stepped bore, whereby a particularly favorable production of the laser spark plug according to the invention or its housing 100 'is possible.
  • the outer opening or the outer opening section 122b of the channel 122 is arranged in the region of an external thread 108 with which the laser spark plug 100 can be screwed into a cylinder head. This advantageously ensures that the channel 122 is sealed to an environment while the laser spark plug 100 is screwed into the cylinder head.
  • an internal thread 122 c may be provided in the channel 122, in which a grub screw is screwed to seal the channel 122.
  • the angle ⁇ of the channel 122 or at least its combustion chamber window 106 facing end portion or its longitudinal axis LA1 is advantageously selected so that an intersection of the respective longitudinal axis with the outer surface 106a of the combustion chamber window 106 a distance Y to the optical axis OA and the Beam path S of the laser spark plug 100 occupies that is at least about 20% of a beam cross section of the laser radiation L in the region of the outer surface 106a, see. the reference symbol S 'in FIG FIG. 5 , preferably at least about 40%, whereby a particularly efficient cleaning is given.
  • the distance between an intersection of the outer edge of the channel 122 in the region 122a with the combustion chamber window 106 from the optical axis OA or the beam path S may be so large that corresponds to the laser beam radius on the outer surface 106a or at least about 75% thereof , see. the reference Y 'in FIG. 5 ,
  • the cleaning fluid can advantageously according to the invention with a hose or a lance, which can be screwed directly or with a flange into an internal thread of the flushing channel 122, are introduced. As already described, the cleaning fluid can then emerge from the "light path" element 120b or the overflow channels 120a 'from the laser spark plug or its prechamber.
  • the channel 122 having at least two different cross-sections, it can be advantageously ensured that when using a lance inserted into the channel 122 from the outside, the lance can not be inserted so deeply into the channel 122 that it contacts comes with the combustion chamber window 106. In addition, this allows an exact determination of the position of the lance can be achieved.
  • a weak, aqueous acid may be provided, for example an aqueous solution of acetic acid, in particular a 30% acetic acid solution.
  • the cleaning fluid may alternatively contain between about 10% and about 80%, preferably between about 15% and about 50% acetic acid (C 2 H 4 O 2 ) diluted in water (H 2 O).
  • aqueous acids which are so weak or diluted so that they do not attack the laser spark plug or the combustion chamber window 106 itself, are also possible, especially if they are oil pockets such as For example, calcium sulfate (anhydride) or calcium phosphate compounds can dissolve.
  • FIG. 6 shows a simplified flowchart of an embodiment of the method according to the invention.
  • a lance (not shown) is introduced from outside into the channel 122 (FIG. FIG. 1 ) to supply the channel 122 with a cleaning fluid.
  • the cleaning fluid is injected under pressure from the lance into the channel 122 and finally onto the combustion chamber window 106 and through the conical opening of the diaphragm 120b (FIG. FIG. 5 ) or the transfer ports 120a 'from the laser spark plug 100 and the interior I' of the prechamber 120a discharged.
  • step 410 may also be advantageously carried out at least one further step, for.
  • neutral liquid e.g. pure water, alcohol (ethanol), isopropanol to protect the candle from corrosion.
  • Advantageous is a fast-drying liquid that evaporates without residue.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Lasers (AREA)
  • Ignition Installations For Internal Combustion Engines (AREA)
  • Fuel-Injection Apparatus (AREA)

Description

Stand der TechnikState of the art

Die Erfindung betrifft eine Laserzündkerze, insbesondere für eine Brennkraftmaschine, mit einem Brennraumfenster, durch das Laserstrahlung aus einem Innenraum der Laserzündkerze hindurch in einen Außenraum abstrahlbar ist, wobei die Laserzündkerze eine den Strahlengang der Laserstrahlung im Bereich des Außenraums zumindest teilweise umgebende Komponente aufweist.The invention relates to a laser spark plug, in particular for an internal combustion engine, having a combustion chamber window through which laser radiation can be emitted from an interior of the laser spark plug into an external space, wherein the laser spark plug has a component which at least partially surrounds the beam path of the laser radiation in the region of the exterior space.

Eine solche Laserzündkerze ist beispielsweise aus der EP 2 072 803 A1 bekannt.Such a laser spark plug is for example from the EP 2 072 803 A1 known.

Die Erfindung betrifft ferner ein Reinigungsverfahren für eine derartige Laserzündkerze.The invention further relates to a cleaning method for such a laser spark plug.

Offenbarung der ErfindungDisclosure of the invention

Es ist Aufgabe der vorliegenden Erfindung, eine Laserzündkerze und ein Reinigungsverfahren der eingangs genannten Art dahingehend zu verbessern, dass eine effiziente Reinigung insbesondere des Brennraumfensters der Laserzündkerze möglich ist.It is an object of the present invention to improve a laser spark plug and a cleaning method of the type mentioned in that an efficient cleaning, in particular of the combustion chamber window of the laser spark plug is possible.

Diese Aufgabe wird bei einer Laserzündkerze der eingangs genannten Art erfindungsgemäß dadurch gelöst, dass die Laserzündkerze im Bereich der Komponente mindestens einen Kanal aufweist, der mindestens zwei Öffnungsabschnitte aufweist und eine Fluidkommunikation zwischen den Öffnungsabschnitten ermöglicht, wobei ein erster Öffnungsabschnitt im Bereich einer Außenoberfläche des Brennraumfensters und ein zweiterThis object is achieved in a laser spark plug of the aforementioned type according to the invention that the laser spark plug in the region of the component has at least one channel having at least two opening portions and a fluid communication between the opening portions allows a first opening portion in the region of an outer surface of the combustion chamber window and a second

Öffnungsabschnitt in einem radial äußeren Bereich der Laserzündkerze, insbesondere der Komponente, angeordnet ist.Opening portion in a radially outer region of the laser spark plug, in particular the component is arranged.

Der erfindungsgemäße Kanal ermöglicht besonders vorteilhaft eine effiziente Beaufschlagung der Außenoberfläche des Brennraumfensters mit einem Fluid, beispielsweise einer Reinigungslösung oder dergleichen. Der erfindungsgemäße Kanal ermöglicht vorteilhaft ferner eine gezielte Einbringung des Reinigungsfluids in den zu reinigenden Bereich der Laserzündkerze.The channel according to the invention particularly advantageously enables an efficient loading of the outer surface of the combustion chamber window with a fluid, for example a cleaning solution or the like. The channel according to the invention advantageously also allows targeted introduction of the cleaning fluid into the region of the laser spark plug to be cleaned.

Bei einer vorteilhaften Ausführungsform ist vorgesehen, dass eine Längsachse wenigstens eines im Bereich des ersten Öffnungsabschnitts angeordneten ersten Längenabschnitts des Kanals im Wesentlichen auf einen radial innen liegenden Bereich einer Außenoberfläche des Brennraumfensters deutet, wodurch unabhängig von einer räumlichen Anordnung des zweiten Öffnungsabschnitts des Kanals eine gezielte Einbringung eines Reinigungsfluids auf den optisch aktiven Bereich des Brennraumfensters ermöglicht ist. D.h., durch die Längsachse des ersten Längenabschnitts, insbesondere ihre Ausrichtung, kann vorteilhaft eine Strömungsrichtung eines durch den Kanal eingebrachten Reinigungsfluids festgelegt bzw. beeinflusst werden.In an advantageous embodiment, it is provided that a longitudinal axis of at least one first longitudinal section of the channel arranged in the region of the first opening section essentially points to a radially inner region of an outer surface of the combustion chamber window, whereby a selective introduction is effected regardless of a spatial arrangement of the second opening section of the channel a cleaning fluid to the optically active region of the combustion chamber window is made possible. In other words, a flow direction of a cleaning fluid introduced through the channel can advantageously be determined or influenced by the longitudinal axis of the first longitudinal section, in particular its orientation.

Besonders vorteilhaft kann einer weiteren Ausführungsform zufolge vorgesehen sein, dass die Längsachse des ersten Längenabschnitts so ausgerichtet ist, dass ein Schnittpunkt der Längsachse mit der Außenoberfläche des Brennraumfensters einen Abstand zur optischen Achse der Laserzündkerze aufweist, der mindestens etwa 20 % eines Strahlungsquerschnitts der Laserstrahlung im Bereich der Außenoberfläche beträgt, vorzugsweise mindestens etwa 40 %. Bei dieser Konfiguration ist Untersuchungen der Anmelderin zufolge eine besonders effiziente Reinigung der Außenoberfläche des Brennraumfensters in demjenigen Oberflächenbereich ermöglicht, durch den von der Laserzündkerze bereitgestellte Laserstrahlung in den Außenraum hindurchtritt.Particularly advantageously, according to a further embodiment, it can be provided that the longitudinal axis of the first longitudinal section is aligned such that an intersection of the longitudinal axis with the outer surface of the combustion chamber window is at a distance from the optical axis of the laser spark plug, which is at least approximately 20% of a radiation cross section of the laser radiation in the region the outer surface is preferably at least about 40%. In this configuration, according to the Applicant, a particularly efficient cleaning of the outer surface of the combustion chamber window is made possible in that surface region through which laser radiation provided by the laser spark plug passes into the outer space.

Bei einer weiteren vorteilhaften Ausführungsform ist vorgesehen, dass mindestens ein zweiter Längenabschnitt des Kanals einen Durchmesser von 0,5 mm bis etwa 4,0 mm, insbesondere von etwa 1,0 mm bis etwa 2,0 mm aufweist. Diese Konfiguration des Kanals ermöglicht eine optimale Beaufschlagung des Brennraumfensters mit unter Druck stehendem Reinigungsfluid, wobei das Reinigungsfluid insbesondere mit einem vergleichsweise hohen Impuls (hoher Druck, hohe Geschwindigkeit) auf das Brennraumfenster einstrahlbar ist und somit dieses reinigt. Neben einer Beaufschlagung des Brennraumfensters mit unter hohem Druck stehenden Reinigungsfluid kann durch den erfindungsgemäßen Kanal vorteilhaft auch eine Benetzung mit Reinigungsfluid erfolgen, das beispielsweise einen verhältnismäßig geringen Druck aufweist. Alternativ oder ergänzend kann eine mechanische Reinigung beispielsweise mit einem Pinsel oder einem Wattestäbchen oder dergleichen durch den Kanal hindurch ausgeführt werden.In a further advantageous embodiment, it is provided that at least a second longitudinal section of the channel has a diameter of 0.5 mm to about 4.0 mm, in particular from about 1.0 mm to about 2.0 mm. This configuration of the channel allows optimal loading of the Combustion chamber window with pressurized cleaning fluid, wherein the cleaning fluid in particular with a comparatively high pulse (high pressure, high speed) is radiated to the combustion chamber window and thus cleans this. In addition to pressurizing the combustion chamber window with cleaning fluid under high pressure, the channel according to the invention can advantageously also be used for wetting with cleaning fluid which, for example, has a relatively low pressure. Alternatively or additionally, a mechanical cleaning, for example with a brush or a cotton swab or the like through the channel can be performed.

Bei einer weiteren vorteilhaften Ausführungsform ist vorgesehen, dass ein im Bereich des ersten Öffnungsabschnitts angeordneter erster Längenabschnitt des Kanals einen Durchmesser von etwa 0,1 mm bis etwa 2,0 mm, insbesondere von etwa 0,2 mm bis etwa 1,0 mm, aufweist.In a further advantageous embodiment, it is provided that a first longitudinal section of the channel arranged in the region of the first opening section has a diameter of approximately 0.1 mm to approximately 2.0 mm, in particular from approximately 0.2 mm to approximately 1.0 mm ,

Sofern der erfindungsgemäße Kanal beispielsweise unterschiedliche Längenabschnitte mit jeweils unterschiedlichen Querschnittsöffnungen bzw. Durchmessern aufweist, kann hierdurch vorteilhaft eine Düsenwirkung für ein durch den Kanal strömendes Reinigungsfluid erzielt werden, wodurch der Impuls des auf das Brennraumfenster gerichteten Reinigungsmittelstroms vorteilhaft beeinflusst werden kann.If, for example, the channel according to the invention has different length sections, each with different cross-sectional openings or diameters, a nozzle effect can advantageously be achieved for a cleaning fluid flowing through the channel, whereby the momentum of the detergent flow directed onto the combustion chamber window can be advantageously influenced.

Bei einer weiteren vorteilhaften Ausführungsform ist der Kanal so ausgebildet, dass er zeitweise so verriegelt werden kann, dass keine Fluidkommunikation zwischen dem ersten und dem zweiten Öffnungsabschnitt möglich ist.In a further advantageous embodiment, the channel is designed so that it can be temporarily locked so that no fluid communication between the first and the second opening portion is possible.

In einer ersten Variante der Erfindung weist der Kanal vorteilhaft zumindest abschnittsweise ein Innengewinde auf, in das eine Madenschraube einschraubbar ist.In a first variant of the invention, the channel advantageously has, at least in sections, an internal thread into which a grub screw can be screwed.

Besonders vorteilhaft kann der Kanal zumindest abschnittsweise als Stufenbohrung ausgebildet sein, so dass eine besonders kostengünstige Fertigung der erfindungsgemäßen Laserzündkerze möglich ist. Generell kann der erfindungsgemäße Kanal jedoch auch eine komplexere Geometrie aufweisen. Insbesondere muss der Kanal nicht notwendig im Wesentlichen Zylinderform aufweisen, sondern kann beispielsweise auch einen oder mehrere gekrümmte Längenabschnitte aufweisen, wodurch eine Richtungsumlenkung des Reinigungsfluids möglich ist. Es ist beispielsweise auch denkbar, den zweiten Öffnungsabschnitt, in den das auf das Brennraumfenster aufzubringende Reinigungsfluid einbringbar ist, in einem brennraumabgewandten axialen Endbereich der Laserzündkerze vorzusehen, wodurch ein Reinigungsfluid beispielsweise auch in einem Einbauzustand der Laserzündkerze in einem Zylinderschacht einer Brennkraftmaschine einbringbar wäre.Particularly advantageously, the channel can be formed at least in sections as a stepped bore, so that a particularly cost-effective production of the laser spark plug according to the invention is possible. In general, however, the channel according to the invention may also have a more complex geometry. In particular, the channel does not necessarily have a substantially cylindrical shape but may for example also have one or more curved lengths, whereby a directional deflection of the cleaning fluid is possible. It is also conceivable, for example, to provide the second opening section into which the cleaning fluid to be applied to the combustion chamber window is provided in an axial end region of the laser spark plug facing away from the combustion chamber, whereby a cleaning fluid, for example, could also be introduced in an installed state of the laser spark plug in a cylinder shaft of an internal combustion engine.

In einer zweiten Variante der Erfindung weist die Laserzündkerze in einem radial äußeren Bereich Befestigungsmittel zur mechanischen Verbindung mit einem Zielsystem auf, nämlich ein Außengewinde, zum Beispiel zum Einschrauben in ein entsprechendes Innengewinde eines Zylinderkopfs einer Brennkraftmaschine. Hierbei liegt der zweite Öffnungsabschnitt im Bereich der Befestigungsmittel. Es folgt insbesondere, dass der zweite Öffnungsabschnitt in einer Einbaulage der Laserzündkerze in dem Zielsystem,verschlossen ist. Dadurch wird vorteilhaft sichergestellt, dass der radial außenseitig an der Laserzündkerze angeordnete zweite Öffnungsabschnitt in der Einbaulage der Laserzündkerze keine direkte Verbindung zu einem Brennraum der Brennkraftmaschine aufweist, in den die Laserzündkerze in ihrer Einbaulage hineinragt.In a second variant of the invention, the laser spark plug in a radially outer region fastening means for mechanical connection with a target system, namely an external thread, for example for screwing into a corresponding internal thread of a cylinder head of an internal combustion engine. In this case, the second opening section lies in the region of the fastening means. It follows in particular that the second opening section is closed in an installed position of the laser spark plug in the target system. This advantageously ensures that the radially arranged on the outside of the laser spark plug second opening portion in the installed position of the laser spark plug has no direct connection to a combustion chamber of the internal combustion engine, in which the laser spark plug protrudes in its installed position.

Einer weiteren vorteilhaften Ausführungsform zufolge kann die den Strahlengang der Laserstrahlung im Bereich des Außenraums zumindest teilweise umgebende Komponente beispielsweise als Blende und/oder als Vorkammer ausgebildet sein. In beiden Fällen erschwert die betreffende Komponente die Zugänglichkeit zu der Außenoberfläche des Brennraumfensters, so dass die Reinigung des Brennraumfensters unter Verwendung des erfindungsgemäßen Kanals besonders zweckmäßig ist. Vorteilhaft kann der Kanal zumindest teilweise in die Blende bzw. eine Vorkammerwand integriert sein.According to another advantageous embodiment, the component which at least partially surrounds the beam path of the laser radiation in the region of the outer space can be formed, for example, as a diaphragm and / or as an antechamber. In both cases, the component in question complicates the accessibility to the outer surface of the combustion chamber window, so that the cleaning of the combustion chamber window using the channel according to the invention is particularly useful. Advantageously, the channel can be at least partially integrated in the diaphragm or an antechamber wall.

Als eine weitere Lösung der Aufgabe der vorliegenden Erfindung ist ein Verfahren gemäß Patentanspruch 12 angegeben.As a further solution to the object of the present invention, a method according to claim 12 is given.

Weitere vorteilhafte Ausgestaltungen sind Gegenstand der Unteransprüche.Further advantageous embodiments are the subject of the dependent claims.

In der Zeichnung zeigt:

Figur 1
schematisch ein laserbasiertes Zündsystem für eine Brennkraftmaschine mit einer eine Vorkammer aufweisenden Laserzündkerze,
Figur 2
schematisch einen brennraumzugewandten Endbereich einer ersten Ausführungsform einer erfindungsgemäßen Laserzündkerze,
Figur 3
schematisch einen teilweisen Querschnitt einer weiteren Ausführungsform der Erfindung,
Figur 4
schematisch einen teilweisen Querschnitt einer erfindungsgemäßen Laserzündkerze mit einer daran angeordneten Reinigungsvorrichtung,
Figur 5
eine Detailansicht eines brennraumzugewandten Endabschnitts einer erfindungsgemäßen Laserzündkerze gemäß einer weiteren Ausführungsform, und
Figur 6
schematisch ein vereinfachtes Flussdiagramm einer Ausführungsform des erfindungsgemäßen Verfahrens.
In the drawing shows:
FIG. 1
1 schematically shows a laser-based ignition system for an internal combustion engine with a laser spark plug that has an antechamber;
FIG. 2
1 schematically shows a combustion chamber-facing end region of a first embodiment of a laser spark plug according to the invention,
FIG. 3
schematically a partial cross section of a further embodiment of the invention,
FIG. 4
FIG. 2 schematically a partial cross section of a laser spark plug according to the invention with a cleaning device arranged thereon, FIG.
FIG. 5
a detailed view of a combustion chamber facing end portion of a laser spark plug according to the invention according to another embodiment, and
FIG. 6
schematically a simplified flow diagram of an embodiment of the method according to the invention.

Figur 1 zeigt schematisch ein laserbasiertes Zündsystem einer Brennkraftmaschine, bei dem eine Laserzündkerze 100 so im Bereich eines Zylinderkopfs der Brennkraftmaschine angeordnet ist, dass ein brennraumzugewandter Endabschnitt der Laserzündkerze 100 in an sich bekannter Weise in den Brennraum 200 der Brennkraftmaschine hineinragt. FIG. 1 schematically shows a laser-based ignition system of an internal combustion engine, in which a laser spark plug 100 is arranged in the region of a cylinder head of the internal combustion engine, that a combustion chamber facing end portion of the laser spark plug 100 protrudes in a conventional manner into the combustion chamber 200 of the internal combustion engine.

Die Laserzündkerze 100 wird vorliegend über Lichtleitermittel 22 mit Pumpstrahlung versorgt, welche von einer Pumplichtquelle 20 bereitgestellt wird. Die Laserzündkerze 100 kann beispielsweise über einen integrierten, passiv gütegeschalteten Festkörperlaser 102 verfügen, der in an sich bekannter Weise unter Beaufschlagung mit dem Pumplicht der Pumplichtquelle 20 energiereiche Laserzündimpulse erzeugt.In the present case, the laser spark plug 100 is supplied with optical radiation via pumping radiation 22, which is provided by a pumping light source 20. The laser spark plug 100 can, for example, have an integrated, passively Q-switched solid-state laser 102, which generates high-energy laser ignition pulses in a manner known per se when exposed to the pump light of the pump light source 20.

Dem Festkörperlaser 102 optisch nachgeordnet ist eine Fokussieroptik 104 zur Bündelung der erzeugten Laserstrahlung auf einen in der Vorkammer 120a liegenden Zündpunkt ZP. Bei anderen Ausführungen (vgl. z. B. Figur 3) liegt der Zündpunkt ZP direkt im Brennraum. Ein Innenraum der Laserzündkerze 100 wird vorliegend durch ein Brennraumfenster 106 zu der Vorkammer 120a hin begrenzt, durch das die Laserstrahlung L hindurchgestrahlt wird.Optically downstream of the solid-state laser 102 is a focusing optics 104 for focusing the generated laser radiation onto an ignition point ZP located in the pre-chamber 120a. For other versions (cf. FIG. 3 ) is the ignition point ZP directly in the combustion chamber. In the present case, an interior of the laser spark plug 100 is delimited by a combustion chamber window 106 toward the prechamber 120a, through which the laser radiation L is transmitted.

Figur 2 zeigt eine Detailansicht eines brennraumzugewandten Endbereichs einer Laserzündkerze gemäß einer Ausführungsform der vorliegenden Erfindung. FIG. 2 shows a detail view of a combustion chamber-facing end portion of a laser spark plug according to an embodiment of the present invention.

Die Laserzündkerze verfügt ähnlich zu der schematischen Abbildung gemäß Figur 1 über eine Vorkammer 120a, in die durch das Brennraumfenster 106 hindurch Laserstrahlung L zur Zündung eines in der Vorkammer 120a befindlichen Luft-/Kraftstoffgemischs einstrahlbar ist.The laser spark plug has similar to the schematic illustration according to FIG. 1 via an antechamber 120a into which laser radiation L for igniting an air / fuel mixture located in the prechamber 120a can be injected through the combustion chamber window 106.

Zum Schutz einer Außenoberfläche 106a des Brennraumfensters 106 weist die Laserzündkerze gemäß Figur 2 eine Blende 120b auf, die auch als "light path" bzw. "light path"-Element bezeichnet wird. Die Blende 120b ermöglicht vermöge ihrer vorliegend etwa kegelstumpfförmigen Öffnung einerseits die Beaufschlagung der Vorkammer 120a mit Laserstrahlung L aus dem in Figur 2 links angeordneten Innenbereich I der Laserzündkerze, während gleichzeitig ein Schutz der Außenoberfläche 106a des Brennraumfensters 106 vor Schmutzpartikeln aus der Vorkammer 120a gegeben ist, weil die Blende 120b die Außenoberfläche 106a des Brennraumfensters 106 zumindest bereichsweise abschirmt.To protect an outer surface 106a of the combustion chamber window 106, the laser spark plug according to FIG. 2 an aperture 120b, also referred to as a "light path" element. The diaphragm 120b, by virtue of its presently approximately frusto-conical opening, on the one hand enables the prechamber 120a to be exposed to laser radiation L from the in FIG. 2 At the same time, protection of the outer surface 106a of the combustion chamber window 106 from dirt particles from the antechamber 120a is provided because the aperture 120b shields the outer surface 106a of the combustion chamber window 106 at least in certain areas.

Die Vorkammer 120a der in Figur 2 abgebildeten Laserzündkerze verfügt ferner über sogenannte Überströmkanäle 120a', die eine Fluidkommunikation zwischen der Vorkammer 120a und dem sie umgebenden Raum 200, beispielsweise dem Brennraum 200 der Brennkraftmaschine, ermöglichen.
Bei herkömmlichen Laserzündkerzen mit Vorkammer kann eine Reinigung des Brennraumfensters 106, insbesondere der Außenoberfläche 106a, nur dadurch erfolgen, dass ein Reinigungsfluid durch die Überströmkanäle 120a' in den Innenraum der Vorkammer 120a eingebracht wird und dort durch die Öffnung der Blende 120b auf die Außenoberfläche 106a des Brennraumfensters 106 tritt. Dadurch ist die Reinigung herkömmlicher Laserzündkerzen mit Vorkammer bzw. Blende aufwendig und hat nur einen verhältnismäßig geringen Effekt.The pre-chamber 120a of in FIG. 2 The illustrated laser spark plug also has so-called transfer ports 120a 'which provide fluid communication between the pre-chamber 120a and the surrounding space 200, for example, the combustion chamber 200 of the internal combustion engine, allow.
In conventional pre-chamber laser spark plugs, the combustion chamber window 106, in particular the outer surface 106a, can only be cleaned by introducing a cleaning fluid through the overflow channels 120a 'into the interior of the prechamber 120a and through the opening of the aperture 120b onto the outer surface 106a of the Combustion window 106 occurs. As a result, the cleaning of conventional laser spark plugs with prechamber or diaphragm is complex and has only a relatively small effect.

Erfindungsgemäß weist die Laserzündkerze daher mindestens einen Kanal 122 auf, der mindestens zwei Öffnungsabschnitte 122a, 122b aufweist und eine Fluidkommunikation zwischen den Öffnungsabschnitten 122a, 122b ermöglicht. Erfindungsgemäß ist vorgesehen, dass ein erster Öffnungsabschnitt 122a des Kanals 122 im Bereich der Außenoberfläche 106a des Brennraumfensters 106 angeordnet ist, und dass ein zweiter Öffnungsabschnitt 122b des Kanals 122 in einem radial äußeren Bereich der Laserzündkerze 100, insbesondere der Blende 120b bzw. der Vorkammer 120a, angeordnet ist.According to the invention, therefore, the laser spark plug has at least one channel 122 which has at least two opening sections 122a, 122b and permits fluid communication between the opening sections 122a, 122b. According to the invention, a first opening section 122a of the channel 122 is arranged in the region of the outer surface 106a of the combustion chamber window 106, and a second opening section 122b of the channel 122 is located in a radially outer region of the laser spark plug 100, in particular the aperture 120b or the pre-chamber 120a , is arranged.

Dadurch kann besonders vorteilhaft in dem radial äußeren Bereich der Laserzündkerze 100 ein Reinigungsfluid von außen in den Kanal 122 eingebracht werden, welches durch den Kanal 122 direkt zu dem zu reinigenden Oberflächenbereich 106a des Brennraumfensters 106 geleitet wird.As a result, it is particularly advantageous in the radially outer region of the laser spark plug 100 for a cleaning fluid to be introduced into the channel 122 from the outside, which is conducted through the channel 122 directly to the surface area 106a of the combustion chamber window 106 to be cleaned.

D. h., bei der Reinigung der erfindungsgemäßen Laserzündkerze 100 findet ein Fluidtransport von Reinigungsfluid aus dem Außenraum 200 bzw. dem radial äußeren Bereich der Vorkammer 120a durch den Kanal 122 hindurch auf die Außenoberfläche 106a des Brennraumfensters 106 statt. Von der Außenoberfläche 106a abprallendes Reinigungsfluid kann die Laserzündkerze bzw. die Vorkammer 120a vorteilhaft durch die Überströmkanäle 120a' verlassen.In other words, during the cleaning of the laser spark plug 100 according to the invention, a fluid transport of cleaning fluid from the outer space 200 or the radially outer region of the pre-chamber 120a through the channel 122 to the outer surface 106a of the combustion chamber window 106 takes place. Cleaning fluid rebounding from the outer surface 106a can advantageously leave the laser spark plug or the prechamber 120a through the overflow passages 120a '.

Bei einer weiteren vorteilhaften Ausführungsform sind mindestens zwei erfindungsgemäße Kanäle 122 vorgesehen, wobei mindestens ein erster Kanal 122 zur Zufuhr von Reinigungsfluid auf das Brennraumfenster 106 verwendet werden kann, während mindestens ein weiterer Kanal (nicht gezeigt) dazu verwendet wird, das zugeführte Reinigungsfluid aus dem Bereich der Vorkammer 120a in den Außenraum 200 abzuführen.
Der erfindungsgemäße Kanal 122 kann auch mehr als zwei Öffnungsabschnitte haben und somit beispielsweise eine Y-förmige Verzweigung (nicht gezeigt) und dergleichen aufweisen, wobei zumindest zwei Öffnungsabschnitte 122a, 122b wie vorstehend beschrieben anzuordnen sind, um eine einfache Reinigung des Brennraumfensters 106 von außerhalb der Laserzündkerze 100 zu ermöglichen.In a further advantageous embodiment, at least two channels 122 according to the invention are provided, wherein at least one first channel 122 can be used to supply cleaning fluid to the combustion chamber window 106, while at least one further channel (not shown) thereto is used to remove the supplied cleaning fluid from the region of the prechamber 120 a in the outer space 200.
The channel 122 according to the invention may also have more than two opening portions and thus, for example, a Y-shaped branch (not shown) and the like, wherein at least two opening portions 122a, 122b are arranged as described above, for easy cleaning of the combustion chamber window 106 from outside the To enable laser spark plug 100.

Bei einer weiteren besonders bevorzugten Ausführungsform der Erfindung, vgl. die Detailansicht aus Figur 5, ist vorgesehen, dass eine Längsachse wenigstens eines im Bereich des ersten Öffnungsabschnitts 122a angeordneten ersten Längenabschnitts LA1 des Kanals 122 im Wesentlichen auf einen radial innen liegenden Bereich B1 der Außenoberfläche 106a des Brennraumfensters 106 deutet, so dass eine effiziente Beaufschlagung des Brennraumfensters 106 mit dem Reinigungsfluid möglich ist.In a further particularly preferred embodiment of the invention, cf. the detail view FIG. 5 , It is provided that a longitudinal axis of at least one arranged in the region of the first opening portion 122 a first length portion LA1 of the channel 122 substantially to a radially inner region B1 of the outer surface 106a of the combustion chamber window 106 indicates, so that an efficient loading of the combustion chamber window 106 with the cleaning fluid is possible.

Bei einer besonders bevorzugten Ausführungsform ist vorgesehen, dass die Längsachse des ersten Längenabschnitts LA1 so ausgerichtet ist, dass ein Schnittpunkt der Längsachse mit der Außenoberfläche 106a des Brennraumfensters 106 einen Abstand Y (Figur 2) zur optischen Achse OA der Laserzündkerze 100 aufweist, der mindestens etwa 20 % eines Strahlquerschnitts der Laserstrahlung L im Bereich der Außenoberfläche 106a beträgt, vorzugsweise mindestens etwa 40 %. Durch diese im Wesentlichen außermittige Beaufschlagung des Brennraumfensters 106 ergibt sich eine besonders gute Reinigungswirkung.In a particularly preferred embodiment it is provided that the longitudinal axis of the first longitudinal section LA1 is aligned so that an intersection of the longitudinal axis with the outer surface 106a of the combustion chamber window 106 is a distance Y (FIG. FIG. 2 ) to the optical axis OA of the laser spark plug 100, which is at least about 20% of a beam cross section of the laser radiation L in the region of the outer surface 106a, preferably at least about 40%. This essentially off-centering of the combustion chamber window 106 results in a particularly good cleaning effect.

Bei einer weiteren vorteilhaften Ausführungsform, vgl. Figur 5, ist vorgesehen, dass mindestens ein zweiter Längenabschnitt LA2 des Kanals 122 einen Durchmesser Z2 von etwa 0,5 mm bis etwa 4,0 mm, insbesondere von etwa 1,0 mm bis etwa 2,0 mm aufweist.In a further advantageous embodiment, cf. FIG. 5 , it is provided that at least a second length section LA2 of the channel 122 has a diameter Z2 of about 0.5 mm to about 4.0 mm, in particular from about 1.0 mm to about 2.0 mm.

Bei einer weiteren vorteilhaften Ausführungsform ist vorgesehen, dass der im Bereich des ersten Öffnungsabschnitts 122a angeordnete Längenabschnitt LA1 des Kanals 122 einen Durchmesser Z1 von etwa 0,1 mm bis etwa 2,0 mm, insbesondere von etwa 0,2 mm bis etwa 1,0 mm, aufweist.In a further advantageous embodiment, it is provided that the longitudinal section LA1 of the channel 122 arranged in the region of the first opening section 122a has a diameter Z1 of approximately 0.1 mm to approximately 2.0 mm, in particular from approximately 0.2 mm to approximately 1.0 mm, has.

Figur 3 zeigt eine weitere Ausführungsform der erfindungsgemäßen Laserzündkerze, bei der die Laserzündkerze nicht mit einer Vorkammer 120a (Figur 2), sondern nur mit einer Blende 120b ausgestattet ist. Auch bei dieser Erfindungsvariante kann mindestens ein Kanal 122 zur Beaufschlagung der Außenoberfläche 106a des Brennraumfensters 106 mit Reinigungsfluid vorgesehen sein. Wie aus Figur 3 ersichtlich, kann die Blende 120b auch einstückig mit dem Gehäuse 100' der Laserzündkerze ausgebildet sein. FIG. 3 shows a further embodiment of the laser spark plug according to the invention, in which the laser spark plug is not provided with an antechamber 120a (FIG. FIG. 2 ), but only with an aperture 120b is equipped. Also in this variant of the invention, at least one channel 122 may be provided for impinging the outer surface 106a of the combustion chamber window 106 with cleaning fluid. How out FIG. 3 As can be seen, the diaphragm 120b may also be formed integrally with the housing 100 'of the laser spark plug.

Figur 4 zeigt eine erfindungsgemäße Laserzündkerze 100 mit dem erfindungsgemäßen Kanal 122, der aufgrund seiner Eignung zur Reinigung der Laserzündkerze 100 bzw. ihres Brennraumfensters 106 auch als Spülkanal bezeichnet wird, und einer um den brennraumzugewandten Endbereich der Laserzündkerze 100 angeordneten Reinigungsvorrichtung 300. Die Reinigungsvorrichtung 300 weist einen Zufluss Z zur Zuführung von Reinigungsfluid auf, das über den Zufluss Z in eine Ringnut R geleitet wird. Die Reinigungsvorrichtung 300 ist so mit der Laserzündkerze 100 mechanisch verbindbar, dass eine Fluidkommunikation auch zwischen der Ringnut R und dem erfindungsgemäßen Spülkanal 122 hergestellt werden kann, vgl. Figur 4. Dadurch kann das der Reinigungsvorrichtung 300 zugeführte Reinigungsfluid von dem Zufluss Z über die Ringnut R in den Spülkanal 122 und damit auf die Außenoberfläche des Brennraumfensters 106 gelangen. FIG. 4 shows a laser spark plug 100 according to the invention with the channel 122 according to the invention, which is also referred to as flushing channel due to its suitability for cleaning the laser spark plug 100 and its combustion chamber window 106, and one around the combustion chamber facing end portion of the laser spark plug 100 arranged cleaning device 300. The cleaning device 300 has an inflow Z for supplying cleaning fluid, which is passed via the inlet Z in an annular groove R. The cleaning device 300 is mechanically connectable to the laser spark plug 100 such that fluid communication can also be established between the annular groove R and the flushing channel 122 according to the invention, cf. FIG. 4 , As a result, the cleaning fluid supplied to the cleaning device 300 can pass from the inflow Z via the annular groove R into the flushing channel 122 and thus onto the outer surface of the combustion chamber window 106.

Ein Rückstrom des auf das Brennraumfenster 106 aufgebrachten Reinigungsfluids kann bei der in Figur 4 abgebildeten Konfiguration durch die Überströmkanäle der Vorkammer zu dem Abfluss A der Reinigungsvorrichtung 300 erfolgen. Das verwendete Fluid kann gefiltert, erneut unter Druck gesetzt und wieder dem Zufluss Z zugeführt werden, so dass sich vorteilhaft eine Kreislauf für das Reinigungsfluid ergibt.A return flow of the cleaning fluid applied to the combustion chamber window 106 may occur at the in FIG. 4 imaged configuration through the overflow channels of the pre-chamber to the outflow A of the cleaning device 300 done. The fluid used can be filtered, pressurized again and fed back to the inlet Z, so that advantageously results in a cycle for the cleaning fluid.

Die Reinigungsvorrichtung 300 kann vorteilhaft auch Mittel zur Temperierung, insbesondere Heizung, des Reinigungsfluids aufweisen, wodurch eine Reinigungsdauer verkürzt werden kann. Die Heizung kann vorteilhaft so konfiguriert sein, dass das Reinigungsfluid nicht bis zu seinem Siedepunkt oder auch bis maximal zu einer vorgebbaren Grenze von ca. 50° C erhitzt wird, um Verbrennungen bei der Handhabung der Vorrichtung 300 zu vermeiden.The cleaning device 300 may advantageously also comprise means for temperature control, in particular heating, of the cleaning fluid, as a result of which a cleaning time can be shortened. The heating may advantageously be configured so that the cleaning fluid is not heated to its boiling point or even to a maximum of a predeterminable limit of about 50 ° C in order to avoid burns when handling the device 300.

Figur 5 zeigt wie bereits erwähnt eine Detailansicht eines brennraumzugewandten Endbereichs einer erfindungsgemäßen Laserzündkerze 100. Ein erster Längenabschnitt LA1 des erfindungsgemäßen Kanals 122 ist wie aus Figur 5 ersichtlich so ausgerichtet, dass er im Wesentlichen auf einen radial inneren, mittleren Bereich der Außenoberfläche 106a des Brennraumfensters 106 weist, wodurch eine präzise Beaufschlagung der optisch aktiven Außenoberfläche des Brennraumfensters 106 mit dem Reinigungsfluid möglich ist. Sofern der erste Längenabschnitt LA1 einen geringeren Durchmesser aufweist als mindestens ein weiterer, sich in axialer Richtung des Kanals 122 daran anschließender zweiter Längenabschnitt LA2, kann in an sich bekannter Weise eine Düsenwirkung für durch den Kanal 122 hindurchströmendes Fluid bewirkt werden, so dass eine Geschwindigkeit des auf das Brennraumfenster 106 einströmenden Reinigungsfluids beeinflusst werden kann. Vorliegend weist der erste Längenabschnitt LA1 einen ersten Durchmesser Z1 auf, und der zweite Längenabschnitt LA2 weist einen zweiten Durchmesser Z2 > Z1 auf. Die in Figur 5 abgebildete Konfiguration des Kanals 122 kann vorteilhaft als Stufenbohrung ausgeführt werden, wodurch eine besonders günstige Fertigung der erfindungsgemäßen Laserzündkerze bzw. ihres Gehäuses 100' möglich ist. FIG. 5 As already mentioned, a detailed view of a combustion chamber-facing end region of a laser spark plug 100 according to the invention is shown. A first longitudinal section LA1 of the channel 122 according to the invention is as shown FIG. 5 can be seen aligned so that it is substantially on a radially inner, central region of the outer surface 106a of the combustion chamber window 106, whereby a precise loading of the optically active outer surface of the combustion chamber window 106 is possible with the cleaning fluid. If the first longitudinal section LA1 has a smaller diameter than at least one further second longitudinal section LA2 adjoining it in the axial direction of the channel 122, a nozzle effect for fluid flowing through the channel 122 can be effected in a manner known per se, so that a speed of the can be influenced on the combustion chamber window 106 incoming cleaning fluid. In the present case, the first longitudinal section LA1 has a first diameter Z1, and the second longitudinal section LA2 has a second diameter Z2> Z1. In the FIG. 5 illustrated configuration of the channel 122 can be advantageously carried out as a stepped bore, whereby a particularly favorable production of the laser spark plug according to the invention or its housing 100 'is possible.

Erfindungsgemäß ist die äußere Öffnung bzw. der äußere Öffnungsabschnitt 122b des Kanals 122 im Bereich eines Außengewindes 108 angeordnet, mit dem die Laserzündkerze 100 in einen Zylinderkopf eingeschraubt werden kann. Dadurch ist vorteilhaft sichergestellt, dass der Kanal 122 zu einer Umgebung hin abgedichtet ist, während die Laserzündkerze 100 in den Zylinderkopf eingeschraubt ist.According to the invention, the outer opening or the outer opening section 122b of the channel 122 is arranged in the region of an external thread 108 with which the laser spark plug 100 can be screwed into a cylinder head. This advantageously ensures that the channel 122 is sealed to an environment while the laser spark plug 100 is screwed into the cylinder head.

Alternativ hierzu kann auch ein Innengewinde 122c in dem Kanal 122 vorgesehen sein, in das eine Madenschraube einschraubbar ist, um den Kanal 122 abzudichten.
Der Winkel α des Kanals 122 oder zumindest seines dem Brennraumfenster 106 zugewandten Endabschnitts bzw. dessen Längsachse LA1 wird einer weiteren Ausführungsform vorteilhaft so gewählt, dass ein Schnittpunkt der entsprechenden Längsachse mit der Außenoberfläche 106a des Brennraumfensters 106 einen Abstand Y zur optischen Achse OA bzw. dem Strahlengang S der Laserzündkerze 100 einnimmt, der mindestens etwa 20 % eines Strahlquerschnitts der Laserstrahlung L im Bereich der Außenoberfläche 106a beträgt, vgl. das Bezugszeichen S' in Figur 5, vorzugsweise mindestens etwa 40 %, wodurch eine besonders effiziente Reinigung gegeben ist.Alternatively, an internal thread 122 c may be provided in the channel 122, in which a grub screw is screwed to seal the channel 122.
The angle α of the channel 122 or at least its combustion chamber window 106 facing end portion or its longitudinal axis LA1 is advantageously selected so that an intersection of the respective longitudinal axis with the outer surface 106a of the combustion chamber window 106 a distance Y to the optical axis OA and the Beam path S of the laser spark plug 100 occupies that is at least about 20% of a beam cross section of the laser radiation L in the region of the outer surface 106a, see. the reference symbol S 'in FIG FIG. 5 , preferably at least about 40%, whereby a particularly efficient cleaning is given.

Alternativ kann der Abstand zwischen einem Schnittpunkt der Außenkante des Kanals 122 im Bereich 122a mit dem Brennraumfenster 106 von der optischen Achse OA bzw. dem Strahlengang S so groß gewählt sein, dass der dem Laserstrahlradius an der Außenoberfläche 106a entspricht oder wenigstens etwa 75% hiervon beträgt, vgl. das Bezugszeichen Y' in Figur 5.Alternatively, the distance between an intersection of the outer edge of the channel 122 in the region 122a with the combustion chamber window 106 from the optical axis OA or the beam path S may be so large that corresponds to the laser beam radius on the outer surface 106a or at least about 75% thereof , see. the reference Y 'in FIG. 5 ,

Das Reinigungsfluid kann erfindungsgemäß vorteilhaft mit einem Schlauch oder einer Lanze, die direkt oder mit einem Flansch in ein Innengewinde des Spülkanals 122 eingeschraubt werden kann, eingebracht werden. Das Reinigungsfluid kann danach wie bereits beschrieben aus dem "light path"-Element 120b bzw. den Überströmkanälen 120a' aus der Laserzündkerze bzw. ihrer Vorkammer austreten.The cleaning fluid can advantageously according to the invention with a hose or a lance, which can be screwed directly or with a flange into an internal thread of the flushing channel 122, are introduced. As already described, the cleaning fluid can then emerge from the "light path" element 120b or the overflow channels 120a 'from the laser spark plug or its prechamber.

Bei der Ausbildung des Kanals 122 mit mindestens zwei unterschiedlichen Querschnitten kann vorteilhaft sichergestellt werden, dass bei der Verwendung einer Lanze, die von außen in den Kanal 122 eingeführt wird, die Lanze nicht so tief in den Kanal 122 eingeführt werden kann, dass sie in Kontakt mit dem Brennraumfenster 106 kommt. Darüber hinaus ist hierdurch eine exakte Festlegung der Position der Lanze erzielbar.In forming the channel 122 having at least two different cross-sections, it can be advantageously ensured that when using a lance inserted into the channel 122 from the outside, the lance can not be inserted so deeply into the channel 122 that it contacts comes with the combustion chamber window 106. In addition, this allows an exact determination of the position of the lance can be achieved.

Als Reinigungsfluid zur Verwendung mit dem mindestens einen erfindungsgemäßen Kanal 122 kann beispielsweise eine schwache, wässrige Säure vorgesehen sein, beispielsweise eine wässrige Lösung von Essigsäure, insbesondere eine 30 %-ige Essigsäurelösung. Das Reinigungsfluid kann alternativ auch zwischen etwa 10 % und etwa 80 %, vorzugsweise zwischen etwa 15 % und etwa 50 % Essigsäure (C2H402) verdünnt in Wasser (H20) enthalten.As a cleaning fluid for use with the at least one channel 122 according to the invention, for example, a weak, aqueous acid may be provided, for example an aqueous solution of acetic acid, in particular a 30% acetic acid solution. The cleaning fluid may alternatively contain between about 10% and about 80%, preferably between about 15% and about 50% acetic acid (C 2 H 4 O 2 ) diluted in water (H 2 O).

Alle anderen wässrigen Säuren, die so weit schwach oder verdünnt sind, so dass sie die Laserzündkerze bzw. das Brennraumfenster 106 selbst nicht angreifen, kommen ebenfalls in Betracht, insbesondere wenn sie Ölaschen wie beispielsweise Kalziumsulfat- (Anhydrid) bzw. Kalziumphosphatverbindungen anlösen können.All other aqueous acids, which are so weak or diluted so that they do not attack the laser spark plug or the combustion chamber window 106 itself, are also possible, especially if they are oil pockets such as For example, calcium sulfate (anhydride) or calcium phosphate compounds can dissolve.

Figur 6 zeigt ein vereinfachtes Flussdiagramm einer Ausführungsform des erfindungsgemäßen Verfahrens. In einem ersten Schritt 400 wird eine Lanze (nicht gezeigt) von außen in den Kanal 122 (Figur 1) eingeführt, um den Kanal 122 mit einem Reinigungsfluid zu versorgen. FIG. 6 shows a simplified flowchart of an embodiment of the method according to the invention. In a first step 400, a lance (not shown) is introduced from outside into the channel 122 (FIG. FIG. 1 ) to supply the channel 122 with a cleaning fluid.

In einem darauf folgenden Schritt 410 wird das Reinigungsfluid unter Druck aus der Lanze in den Kanal 122 und schließlich auf das Brennraumfenster 106 eingestrahlt und durch die kegelförmige Öffnung der Blende 120b (Figur 5) bzw. die Überströmkanäle 120a' aus der Laserzündkerze 100 bzw. dem Innenraum I' der Vorkammer 120a abgeführt.In a subsequent step 410, the cleaning fluid is injected under pressure from the lance into the channel 122 and finally onto the combustion chamber window 106 and through the conical opening of the diaphragm 120b (FIG. FIG. 5 ) or the transfer ports 120a 'from the laser spark plug 100 and the interior I' of the prechamber 120a discharged.

Bei einer weiteren Ausführungsform kann auf den Schritt 410 vorteilhaft auch mindestens ein weiterer Schritt erfolgen, z. B. das Nachspülen mit neutraler Flüssigkeit, z.B. reines Wasser, Spiritus (Ethanol), Isopropanol, um die Kerze vor Korrosion zu schützen. Vorteilhaft ist eine schnell trocknende Flüssigkeit, die rückstandsfrei verdunstet.In a further embodiment, step 410 may also be advantageously carried out at least one further step, for. For example, rinsing with neutral liquid, e.g. pure water, alcohol (ethanol), isopropanol to protect the candle from corrosion. Advantageous is a fast-drying liquid that evaporates without residue.

Claims (13)

  1. Laser spark plug (100), in particular for an internal combustion engine, having a combustion chamber window (106) through which laser radiation (L) can be irradiated from an interior space (I) of the laser spark plug (100) into an external space (A), wherein the laser spark plug (100) has a component (120a, 120b) which at least partially surrounds the beam path (S) of the laser radiation (L) in the region of the external space (A), characterized in that the laser spark plug (100) has, in the region of the component (120a, 120b), at least one channel (122) which has at least two opening sections (122a, 122b) and permits fluid communication between the opening sections (122a, 122b), wherein a first opening section (122a) is arranged in the region of an external surface (106a) of the combustion chamber window (106) and a second opening section (122b) is arranged in a radially outer region of the laser spark plug (100), in particular of the component (120a, 120b), and wherein the channel (122) has, at least in certain sections, an internal thread (122c) for receiving a grub screw.
  2. Laser spark plug (100), in particular for an internal combustion engine, having a combustion chamber window (106) through which laser radiation (L) can be irradiated from an interior space (I) of the laser spark plug (100) into an external space (A), wherein the laser spark plug (100) has a component (120a, 120b) which at least partially surrounds the beam path (S) of the laser radiation (L) in the region of the external space (A), characterized in that the laser spark plug (100) has, in the region of the component (120a, 120b), at least one channel (122) which has at least two opening sections (122a, 122b) and permits fluid communication between the opening sections (122a, 122b), wherein a first opening section (122a) is arranged in the region of an external surface (106a) of the combustion chamber window (106) and a second opening section (122b) is arranged in a radially outer region of the laser spark plug (100), in particular of the component (120a, 120b), and wherein the laser spark plug (100) has an external thread (108) in a radially outer region, and in that the second opening section (122b) lies in the region of the external thread.
  3. Laser spark plug (100) according to Claim 1 or 2, wherein a longitudinal axis of at least one first longitudinal section (LA1) of the channel (122), arranged in the region of the first opening section (122a), points essentially to a radially inner region (B1) of an external surface (106a) of the combustion chamber window (106).
  4. Laser spark plug (100) according to Claim 3, wherein the longitudinal axis of the first longitudinal section (LA1) is oriented in such a way that an intersection point of the longitudinal axis with the external surface (106a) of the combustion chamber window (106) is at a distance (Y) from the optical axis (OA) of the laser spark plug (100), which distance (Y) is at least approximately 20 percent of a beam cross section of the laser radiation (L) in the region of the external surface (106a).
  5. Laser spark plug (100) according to Claim 3, wherein the longitudinal axis of the first longitudinal section (LA1) is oriented in such a way that an intersection point of the longitudinal axis with the external surface (106a) of the combustion chamber window (106) is at a distance (Y) from the optical axis (OA) of the laser spark plug (100), which distance (Y) is at least approximately 40 percent of a beam cross section of the laser radiation (L) in the region of the external surface (106a).
  6. Laser spark plug (100) according to one of the preceding claims, wherein at least one second longitudinal section (LA2) of the channel (122) a diameter (Z2) of approximately 0.5 mm to approximately 4.0 mm.
  7. Laser spark plug (100) according to one of the preceding claims, wherein at least one second longitudinal section (LA2) of the channel (122) has a diameter (Z2) of approximately 1.0 mm to approximately 2.0 mm.
  8. Laser spark plug (100) according to one of the preceding claims, wherein a or the first longitudinal section (LA1) of the channel (122) which is arranged in the region of the first opening section (122a) has a diameter (Z2) of approximately 0.1 mm to approximately 2.0 mm.
  9. Laser spark plug (100) according to one of the preceding claims, wherein a or the first longitudinal section (LA1) of the channel (122) which is arranged in the region of the first opening section (122a) has a diameter (Z2) of approximately 0.2 mm to approximately 1.0 mm.
  10. Laser spark plug (100) according to one of the preceding claims, wherein the channel (122) is embodied at least in certain sections as a stepped borehole.
  11. Laser spark plug (100) according to one of the preceding claims, wherein the component (120a, 120b) is a diaphragm and/or an antechamber.
  12. Method for cleaning a laser spark plug (100) according to one of the preceding claims, characterized in that a cleaning fluid and/or ultrasound are/is applied to the second opening section (122b).
  13. Method according to Claim 12, wherein a lance is introduced at least partially into the second opening section (122b) in order to feed in the cleaning fluid and/or ultrasound.
EP12724610.6A 2011-07-13 2012-05-29 Laser spark plug and cleaning method for same Not-in-force EP2732149B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102011079043A DE102011079043A1 (en) 2011-07-13 2011-07-13 Laser spark plug and cleaning method therefor
PCT/EP2012/059957 WO2013007439A1 (en) 2011-07-13 2012-05-29 Laser spark plug and cleaning method for same

Publications (2)

Publication Number Publication Date
EP2732149A1 EP2732149A1 (en) 2014-05-21
EP2732149B1 true EP2732149B1 (en) 2017-03-01

Family

ID=46197252

Family Applications (1)

Application Number Title Priority Date Filing Date
EP12724610.6A Not-in-force EP2732149B1 (en) 2011-07-13 2012-05-29 Laser spark plug and cleaning method for same

Country Status (5)

Country Link
US (1) US9982651B2 (en)
EP (1) EP2732149B1 (en)
JP (1) JP6021907B2 (en)
DE (1) DE102011079043A1 (en)
WO (1) WO2013007439A1 (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010029398A1 (en) * 2010-05-27 2011-12-01 Robert Bosch Gmbh Laser-induced spark ignition for an internal combustion engine
DE102011079017A1 (en) * 2011-07-12 2013-01-17 Robert Bosch Gmbh Method and device for operating a laser spark plug
JP6457759B2 (en) * 2014-07-31 2019-01-23 三菱重工エンジン＆ターボチャージャ株式会社 Engine with laser spark plug
JP6478509B2 (en) * 2014-07-31 2019-03-06 株式会社Ｓｏｋｅｎ Laser igniter
EP3045715A1 (en) 2015-01-16 2016-07-20 Caterpillar Energy Solutions GmbH Laser ignited pre-combustion chamber assembly
EP3045713A1 (en) 2015-01-16 2016-07-20 Caterpillar Energy Solutions GmbH Laser ignited pre-combustion chamber assembly
RU2634301C2 (en) * 2015-12-29 2017-10-25 Николай Борисович Болотин Laser ignition system and laser ignition plug
RU2612188C1 (en) * 2016-01-29 2017-03-02 Николай Борисович Болотин Diesel engine ignition system and laser sparking plug
US11519378B2 (en) * 2020-05-19 2022-12-06 Wisconsin Alumni Research Foundation Internal combustion engine with laser-assisted, compression ignition

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5588074U (en) * 1978-12-14 1980-06-18
JP3137490B2 (en) 1993-02-26 2001-02-19 三菱重工業株式会社 Laser ignition device
JPH09250438A (en) * 1996-03-14 1997-09-22 Mitsubishi Heavy Ind Ltd Engine ignition device
DE102006028274A1 (en) * 2006-06-20 2007-12-27 Robert Bosch Gmbh Optical distributor and operating method therefor
DE102007015036B4 (en) * 2007-03-29 2008-11-20 Multitorch Gmbh Laser ignition for gas mixtures
DE102007046312A1 (en) * 2007-09-27 2009-04-02 Robert Bosch Gmbh Laser device for the ignition device of an internal combustion engine
US7770552B2 (en) * 2007-10-31 2010-08-10 Caterpillar Inc. Laser igniter having integral pre-combustion chamber
AT505766B1 (en) * 2007-12-19 2009-04-15 Ge Jenbacher Gmbh & Co Ohg DEVICE FOR COUPLING LASER LIGHT INTO A COMBUSTION CHAMBER OF AN INTERNAL COMBUSTION ENGINE
AT506200B1 (en) * 2007-12-19 2009-09-15 Ge Jenbacher Gmbh & Co Ohg DEVICE FOR IGNITING A FUEL / AIR MIXTURE IN THE COMBUSTION ENGINE OF AN INTERNAL COMBUSTION ENGINE
DE102008043961A1 (en) * 2008-11-21 2010-05-27 Robert Bosch Gmbh Laser-induced spark ignition for an internal combustion engine
US20100260454A1 (en) * 2009-04-10 2010-10-14 Raytheon Company Laser to optical fiber coupling device and method
AT508983B1 (en) * 2009-10-07 2012-12-15 Ge Jenbacher Gmbh & Co Ohg LASER SPARK PLUG FOR INTERNAL COMBUSTION ENGINE
AT508801B1 (en) * 2009-10-07 2011-09-15 Ge Jenbacher Gmbh & Co Ohg BRENNKRAFTMASCHINENZÜNDVORRICHTUNG
DE102009047019A1 (en) * 2009-11-23 2011-05-26 Robert Bosch Gmbh laser spark plug
JP5588074B2 (en) 2011-12-05 2014-09-10 インターナショナル・ビジネス・マシーンズ・コーポレーション Privacy information management apparatus, method and program
JP6249123B1 (en) 2017-04-12 2017-12-20 栗田工業株式会社 Scale inhibitor and scale prevention method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Also Published As

Publication number Publication date
JP6021907B2 (en) 2016-11-09
JP2014523995A (en) 2014-09-18
US20140305394A1 (en) 2014-10-16
EP2732149A1 (en) 2014-05-21
DE102011079043A1 (en) 2013-01-17
US9982651B2 (en) 2018-05-29
WO2013007439A1 (en) 2013-01-17

Similar Documents

Publication Publication Date Title
EP2732149B1 (en) Laser spark plug and cleaning method for same
DE102008040429A1 (en) Flow protection device on a laser spark plug to improve the ignition behavior
EP2577043B1 (en) Laser-induced spark ignition for an internal combustion engine
DE102008062574A1 (en) spark plug
DE102006018973A1 (en) Air/fuel mixture laser ignition method for internal combustion engine, involves igniting air/fuel mixture by using laser ignition in pre-chamber during approximation at upper dead center of piston
WO2011041807A2 (en) Laser spark plug for an internal combustion engine
DE102010029398A1 (en) Laser-induced spark ignition for an internal combustion engine
DE102010029385A1 (en) Laser-induced spark ignition for an internal combustion engine
DE102010029347A1 (en) Laser-induced spark ignition for an internal combustion engine
WO2011060987A1 (en) Laser spark plug
WO2012152471A1 (en) Laser spark plug
DE102011075385A1 (en) Laser spark plug and operating method therefor
WO2011138087A2 (en) Laser ignition device for an internal combustion engine
DE4244400C2 (en) Burners for hot gas generation
DE102016101922B3 (en) Fuel Einspritzinjektor
DE102010029402A1 (en) Laser spark plug for combustion engine of motor car, has cover plate whose inner contour includes edge in region, which is spaced from cover plate end facing toward chamber and from another cover plate end facing away from chamber
EP4431710A1 (en) Mounting component for a pre-chamber component of a combustion engine
DE102013212065A1 (en) Method for mounting a laser spark plug
DE102011083450A1 (en) Rotary piston combustion engine e.g. Wankel engine has laser ignition system that is provided to irradiate laser light on ignition dot formed in combustion chamber
DE102010029353A1 (en) Laser-induced spark ignition for an internal combustion engine
DE102010029412A1 (en) Laser spark plug for internal combustion engine, has unit for guiding, shaping or generating laser radiation, combustion chamber window and housing
WO2011147619A1 (en) Laser-induced spark ignition unit for an internal combustion engine
DE102010029415A1 (en) Laser spark plug for combustion engine of motor car, has overflow duct designed such that fluid flow enters into interior of diaphragm, and vortex rotating around vortex axis and comprising component along longitudinal axis of plug
DE102010029351A1 (en) Laser spark plug for combustion engine of motor car, has housing including cover plate for passing laser radiation into combustion chamber, where cover plate completely or partially made of material with specific range of heat conductivity
DE102010029406A1 (en) Laser ignition plug for use in internal combustion engine of motor vehicle, has housing comprising cover for guiding laser radiation into combustion chamber, where distance between cover and laser radiation is less than specific mm

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20140213

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
17Q First examination report despatched

Effective date: 20150414

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

INTG Intention to grant announced

Effective date: 20161207

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

Ref country code: AT

Ref legal event code: REF

Ref document number: 871687

Country of ref document: AT

Kind code of ref document: T

Effective date: 20170315

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: LANGUAGE OF EP DOCUMENT: GERMAN

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 502012009645

Country of ref document: DE

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 6

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20170301

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG4D

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170602

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: NO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170601

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170601

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170531

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170701

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170703

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 502012009645

Country of ref document: DE

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: MC

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

26N No opposition filed

Effective date: 20171204

REG Reference to a national code

Ref country code: IE

Ref legal event code: MM4A

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170531

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170531

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170529

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20170531

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170529

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 7

REG Reference to a national code

Ref country code: AT

Ref legal event code: MM01

Ref document number: 871687

Country of ref document: AT

Kind code of ref document: T

Effective date: 20170529

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170529

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170531

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: HU

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO

Effective date: 20120529

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20190521

Year of fee payment: 8

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CY

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170301

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20190716

Year of fee payment: 8

Ref country code: GB

Payment date: 20190523

Year of fee payment: 8

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: TR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20170301

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 502012009645

Country of ref document: DE

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20200529

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20200529

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20200531

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20201201