EP2477286B1 - Bougie d'allumage - Google Patents

Bougie d'allumage Download PDF

Info

Publication number
EP2477286B1
EP2477286B1 EP12151260.2A EP12151260A EP2477286B1 EP 2477286 B1 EP2477286 B1 EP 2477286B1 EP 12151260 A EP12151260 A EP 12151260A EP 2477286 B1 EP2477286 B1 EP 2477286B1
Authority
EP
European Patent Office
Prior art keywords
ground electrode
side tip
electrode side
face
center electrode
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.)
Active
Application number
EP12151260.2A
Other languages
German (de)
English (en)
Other versions
EP2477286A2 (fr
EP2477286A3 (fr
Inventor
Kenji Ban
Tomoaki Kato
Yoshikazu Kataoka
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.)
Niterra Co Ltd
Original Assignee
NGK Spark Plug Co Ltd
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 NGK Spark Plug Co Ltd filed Critical NGK Spark Plug Co Ltd
Publication of EP2477286A2 publication Critical patent/EP2477286A2/fr
Publication of EP2477286A3 publication Critical patent/EP2477286A3/fr
Application granted granted Critical
Publication of EP2477286B1 publication Critical patent/EP2477286B1/fr
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T13/00—Sparking plugs
    • H01T13/20—Sparking plugs characterised by features of the electrodes or insulation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T13/00—Sparking plugs
    • H01T13/02—Details
    • H01T13/16—Means for dissipating heat
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T13/00—Sparking plugs
    • H01T13/20—Sparking plugs characterised by features of the electrodes or insulation
    • H01T13/39—Selection of materials for electrodes

Definitions

  • the present invention relates to a spark plug used in an internal combustion engine, or the like.
  • a spark plug used in a combustion device such as an internal combustion engine includes, for example, a center electrode extending in a direction of the axis, an insulating body provided on the outer periphery of the center electrode, a hollow cylindrical metal shell provided on the outer periphery of the insulating body, and a bar-like ground electrode of which one end portion is joined to the leading end portion of the metal shell.
  • the ground electrode is disposed with an approximately intermediate portion thereof bent back in such a way that the leading end portion thereof is opposed to the leading end portion of the center electrode, thereby forming a spark discharge gap between the leading end portion of the center electrode and the other end portion of the ground electrode.
  • a technology is known whereby a noble metal tip is provided in a region of the other end portion of the ground electrode which forms the spark discharge gap, thus achieving an improvement in wear resistance and ignitability.
  • the ground electrode is disposed protruding toward the central side of a combustion chamber. For this reason, there is a danger that the ground electrode is overheated, and that preignition (premature ignition) occurs due to the high temperature ground electrode, or erosion or breakage occurs in the ground electrode.
  • a technique (a so-called transverse discharge type of spark plug) whereby the ground electrode is made comparatively short, and the leading end face of the ground electrode (a noble metal tip) is opposed to the side surface of the leading end portion of the center electrode, thus generating a spark discharge in a direction approximately perpendicular to the axis (for example, refer to Patent Document 1 or the like).
  • the technique as it is possible to reduce the amount of heat received by the ground electrode, and it becomes easier to transfer the heat in the ground electrode to the metal shell side, it is possible to improve thermal resistance. Also, as it is possible to cause a flame kernel to grow smoothly toward the central side of the combustion chamber without the growth being inhibited by the ground electrode, it is possible to sufficiently maintain ignitability.
  • JP-A-2009-151984 JP 2009 200002 A describes a spark plug.
  • JP 2009 151984 describes a spark plug.
  • the invention having been contrived bearing in mind the heretofore described circumstances, has an object of providing a spark plug having a ground electrode or noble metal tip opposed to the side surface of the leading end portion of a center electrode, wherein it is possible to realize performance superior in both ignitability and wear resistance.
  • a spark plug of this configuration includes:
  • first tangent line and second tangent line mean two tangent lines which do not intersect with each other between the side corresponding to the other end face of the ground electrode side tip and the projection region corresponding to the leading end face of the center electrode side tip.
  • a configuration is adopted such that the relative positions of the ground electrode side tip and center electrode side tip satisfy 0.12 ⁇ SA1 ⁇ SA2/G. Consequently, it is possible to suppress an increase in discharge voltage, and it is possible to more reliably prevent a spark discharge being generated between only small portions of the ground electrode side tip and center electrode side tip, and the ground electrode side tip and the like wearing out locally. As a result of this, it is possible to effectively improve wear resistance.
  • a configuration is adopted such that SA1 ⁇ SA2/G ⁇ 0.49 is satisfied. Consequently, it is possible to more reliably prevent a flame kernel growth inhibition due to the existence of the ground electrode side tip or center electrode side tip, and it is possible to prevent a situation in which a discharge position varies in the extreme. As a result of this, it is possible to realize superior ignitability while sufficiently maintaining the wear resistance improvement effect.
  • a configuration is adopted such that the distance B is set to 0.3mm or more, and the ground electrode side tip has a sufficient thickness. Consequently, it is possible to suppress an overheating in the ground electrode side tip, and it is possible to secure a sufficient wear volume in the ground electrode side tip.
  • a configuration is adopted such that the distance A is set to 0.05mm or more, and the area in which the center electrode side tip and ground electrode side tip are opposed to each other is not reduced to an extreme. Because of this, it is possible to more reliably prevent a situation in which spark discharges with an edge portion of each of the center electrode side tip and ground electrode side tip as a base point are concentrically generated, and the edge portions wear out unevenly.
  • the working effect achieved by setting the distance B to 0.3mm or more and the working effect achieved by setting the distance A to 0.05mm or more act synergetically, and it is thus possible to achieve a further improvement in wear resistance.
  • a configuration is adopted such that the distance B is set to 0.7mm or less, and the thickness of the ground electrode side tip is not excessively increased. Consequently, it is possible to more reliably prevent a situation in which a flame kernel growth is inhibited, or heat is removed from a flame kernel, by the ground electrode side tip.
  • the distance A is set to "B+0.2mm" or less, and the amount by which the center electrode side tip protrudes toward the leading end side in the direction of the axis thereof with respect to the other end face of the ground electrode side tip is not excessively increased. Consequently, it is possible to cause a flame kernel to grow toward the central side of a combustion chamber without the growth being inhibited by the center electrode side tip.
  • the center electrode side tip is joined to a base material of the center electrode via a welded junction formed by a laser welding or the like, it is possible, by setting the distance A to "B+0.2mm" or less, to space the other end face of the ground electrode side tip from the welded junction. Because of this, it is possible to more reliably prevent a spark discharge being generated between the ground electrode side tip and welded junction (that is, at a position away from the center of the combustion chamber).
  • the working effect achieved by setting the distance B to 0.7mm or less and the working effect achieved by setting the distance A to "B+0.2mm” or less act synergetically, and it is thus possible to still further improve ignitability.
  • the spark discharge gap size G is set to 1.0mm or less, it is possible to more reliably suppress an increase in discharge voltage, and furthermore, as the area SX is set to 0.3mm 2 or more, it is possible to secure a still larger wear volume of the ground electrode side tip. Because of this, it is possible to achieve a further improvement in wear resistance.
  • the spark discharge gap size G is set to 0.4mm or more, and the area SX is set to 0.6mm 2 or less, it is possible to more effectively suppress a flame kernel growth inhibition due to the ground electrode side tip or the like. As a result of this, it is possible to further improve ignitability.
  • a spark plug of this configuration includes:
  • third tangent line and “fourth tangent line” mean two tangent lines which do not intersect with each other between the side corresponding to the other end face of the ground electrode and the projection region corresponding to the leading end face of the center electrode.
  • the center electrode side tip is provided at the leading end portion of the center electrode, or it may be arranged that the center electrode side tip is not provided at the leading end portion of the center electrode.
  • the spark plug according to the configuration 1 or 2 is characterized in that when a cross-sectional area of the ground electrode is taken to be SY (mm 2 ), and the width of the ground electrode is taken to be W (mm), on any cross section, of a portion from the longitudinal center to the one end of the ground electrode, in a direction perpendicular to a central axis of the ground electrode, 2.3 ⁇ SY ⁇ 3.5 and 1.8 ⁇ W ⁇ 2.2 are satisfied.
  • the cross-sectional area SY on one end side (the side on which the ground electrode is fixed to the metal shell) of the ground electrode is set to 2.3mm 2 or more, it is possible to efficiently transfer heat from the other end portion to the one end side (metal shell side) of the ground electrode.
  • the thickness of the ground electrode is excessively increased when the width of the ground electrode is reduced to an extreme, meaning that the ground electrode takes a form in which it protrudes toward the central side of the combustion chamber, and there is concern that the ground electrode is overheated, but as the width W is set to 1.8mm or more, it is possible to dispel the concern. That is, by setting the width W to 1.8mm or more while setting the cross-sectional area SY to 2.3mm 2 or less, it is possible to achieve a further improvement in thermal resistance with a transverse discharge type of spark plug commonly superior in thermal resistance.
  • the cross-sectional area SY is set to 3.5mm 2 or less, it is possible to more reliably prevent heat being removed from a flame kernel by the ground electrode, and as the width W is set to 2.2mm or less, it is possible to effectively suppress a flame kernel growth inhibition due to the ground electrode. As a result of this, it is possible to achieve a still further improvement in ignitability.
  • the spark plug according to any one of the configurations 1 to 3 is characterized in that the ground electrode includes an outer layer and an inner layer, provided inside the outer layer, which is formed from a metal with better thermal conductivity than the outer layer, and when a cross-sectional area of the inner layer is taken to be SI (mm 2 ), and the cross-sectional area of the ground electrode is taken to be SZ (mm 2 ), on a cross section on which the cross-sectional area of the inner layer is largest in a direction perpendicular to the central axis of the ground electrode, 0.2 ⁇ SI/SZ ⁇ 0.5 is satisfied.
  • a configuration is adopted such that the inner layer superior in thermal conductivity is provided inside the ground electrode, and 0.2 ⁇ SI/SZ is satisfied (that is, the inner layer has a sufficient volume with respect to the ground electrode). Consequently, it is possible to dramatically enhance the thermal conductivity of the ground electrode, and it is possible to very effectively improve thermal resistance.
  • the spark plug according to any one of the configurations 1 to 4 is characterized in that both side surfaces of the ground electrode adjacent to an opposite surface of the ground electrode opposed to the center electrode form a curved shape convex outward, and when the curvature radii of the external lines of the two side surfaces are taken to be R (mm) on a cross section perpendicular to the central axis of the ground electrode, R ⁇ 1.5 is satisfied.
  • each “curvature radius R” refers to the curvature radius of a virtual circle, on a cross section perpendicular to the central axis of the ground electrode, passing through three points, one end point and the other end point of the external line of each corresponding side surface, and the midpoint between the two points.
  • both side surfaces of the ground electrode are formed into a convexly curved surface, it becomes easier for a fuel gas to infiltrate into the gap, and it is thus possible to further improve ignitability.
  • Fig. 1 is a partially sectioned front view showing a spark plug 1.
  • a description will be given with a direction of an axis CL1 of the spark plug 1 as an up-down direction in the drawing, the lower side as the leading end side of the spark plug 1, and the upper side as the rear end side.
  • the spark plug 1 is configured of a hollow cylindrical insulator 2 acting as an insulating body, a hollow cylindrical metal shell 3 which holds the insulator 2, and the like.
  • the insulator 2 being formed by sintering alumina or the like, as is well known, includes in the external portion thereof a rear end side barrel portion 10 formed on the rear end side, a large diameter portion 11 formed closer to the leading end side than the rear end side barrel portion 10 so as to protrude outward in a radial direction, a middle barrel portion 12 formed closer to the leading end side than the large diameter portion 11 so as to be smaller in diameter than the large diameter portion 11, and an insulator nose length portion 13 formed closer to the leading end side than the middle barrel portion 12 so as to be smaller in diameter than the middle barrel portion 12.
  • the large diameter portion 11, the middle barrel portion 12, and the larger proportion of the insulator nose length portion 13, of the insulator 2 are housed inside the metal shell 3.
  • a tapered shoulder 14 is formed at the junction of the middle barrel portion 12 and insulator nose length portion 13, and the insulator 2 is retained on the metal shell 3 by the shoulder 14.
  • an axial hole 4 extending along the axis CL1 is formed in the insulator 2 so as to pass through the insulator 2, and a center electrode 5 is inserted and fixed on the leading end side of the axial hole 4.
  • the center electrode 5 has a bar-like (cylindrical) shape as a whole, and a leading end portion thereof protrudes from the leading end of the insulator 2.
  • the center electrode 5 includes an inner layer 5A formed from copper or a copper alloy and an outer layer 5B formed from an Ni alloy with nickel (Ni) as a primary component.
  • a noble metal for example, platinum or iridium
  • a terminal electrode 6 is inserted and fixed on the rear end side of the axial hole 4 in a condition in which it protrudes from the rear end of the insulator 2.
  • a cylindrical resistor 7 is disposed between the center electrode 5 and terminal electrode 6 in the axial hole 4. Both end portions of the resistor 7 are electrically connected to the center electrode 5 and terminal electrode 6 via electrically conductive glass seal layers 8 and 9 respectively.
  • the metal shell 3 is formed in a hollow cylindrical shape from a metal such as a low carbon steel, and a thread portion (a male thread portion) 15 for mounting the spark plug 1 on a combustion device such as an internal combustion engine or a fuel cell reformer is formed on the outer peripheral surface of the metal shell 3.
  • a seat 16 is formed on the rear end side of the thread portion 15 so as to protrude toward the outer peripheral side, and a ring-like gasket 18 is fitted over a thread neck 17 at the rear end of the thread portion 15.
  • a tool engagement portion 19 of hexagonal cross section for engaging a tool such as a wrench when mounting the metal shell 3 in the combustion device is provided on the rear end side of the metal shell 3.
  • a caulked portion 20 bent inward in the radial direction is provided on the rear end side of the metal shell 3.
  • a tapered shoulder 21 for retaining the insulator 2 is provided on the inner peripheral surface of the metal shell 3. Then, the insulator 2 is inserted from the rear end side toward the leading end side of the metal shell 3, and fixed to the metal shell 3 by caulking a rear end side opening portion of the metal shell 3 inward in the radial direction, that is, forming the caulked portion 20, in a condition in which the shoulder 14 of the insulator 2 is retained by the shoulder 21 of the metal shell 3.
  • An annular plate packing 22 is interposed between the shoulders 14 and 21 of both the insulator 2 and the metal shell 3.
  • annular ring members 23 and 24 are interposed between the metal shell 3 and the insulator 2 on the rear end side of the metal shell 3, and a space between the ring members 23 and 24 is filled with talc 25 powder. That is, the metal shell 3 holds the insulator 2 across the plate packing 22, ring members 23 and 24, and talc 25.
  • a ground electrode 27 having a bar-like shape is joined to a leading end portion 26 of the metal shell 3.
  • a configuration is adopted such that the distance between the leading end of the inner layer 27I and the other end of the ground electrode 27 is sufficiently small (for example, 2mm or less).
  • both side surfaces 27S1 and 27S2 adjacent to an opposite surface 27T opposed to the center electrode side tip 31 (positioned on the center electrode 5 side) have a curved shape convex outward, on any cross section in a direction perpendicular to a central axis CL2 of the ground electrode 27, as shown in Fig. 3 .
  • the curvature radii of the external lines of both side surfaces 27S 1 and 27S2 are taken to be R1 (mm) and R2 (mm) respectively on a cross section perpendicular to the central axis CL2 of the ground electrode 27, a configuration is adopted such that R1 ⁇ 1.5 and R2 ⁇ 1.5 are satisfied.
  • each "curvature radius R1 and R2" refers to the curvature radius of a virtual circle passing through three points, one end point and the other end point of the external line of each corresponding side surface 27S1 and 27S2, and the midpoint between the two points.
  • the ground electrode 27 is configured in such a way as to have an approximately constant width and cross-sectional area in its longitudinal direction, and when the cross-sectional area of the ground electrode 27 is taken to be SY (mm 2 ), and the width of the ground electrode 27 is taken to be W (mm), on any cross section in a direction perpendicular to the central axis CL2 of the ground electrode 27, a configuration is adopted such that 2.3 ⁇ SY ⁇ 3.5 and 1.8 ⁇ W ⁇ 2.2 are satisfied.
  • a configuration is adopted such that the cross-sectional area SY and the like satisfy the heretofore mentioned expressions on any cross section in a direction perpendicular to the central axis CL2, but it is sufficient that a configuration is adopted such that the cross-sectional area SY and the like satisfy the heretofore mentioned expressions on any cross section, in a direction perpendicular to the central axis CL2, of a portion from the longitudinal center of the ground electrode 27 to the one end of the ground electrode 27.
  • SI and SZ are set so as to satisfy 0.2 ⁇ SI/SZ ⁇ 0.5.
  • the cross-sectional area of the inner layer 27I in a direction perpendicular to the central axis CL2 of the ground electrode 27 is set to 0.2 times or more the cross-sectional area of the ground electrode 27.
  • a ground electrode side tip 32 formed from a metal containing a noble metal is joined to the leading end side of the opposite surface 27T of the ground electrode 27 in such a way as to protrude from another end face 27F of the ground electrode 27.
  • the ground electrode side tip 32 has a rectangular cross-sectional shape (refer to Fig. 4 ), and one end portion thereof is joined to the ground electrode 27 in a condition in which one portion of the one end portion is buried into the ground electrode 27.
  • another end face 32F of the ground electrode side tip 32 is opposed to the side surface of the leading end portion of the center electrode side tip 31.
  • a spark discharge gap 33 acting as a gap is formed between the side surface of the center electrode side tip 31 and the other end face 32F of the ground electrode side tip 32, and an arrangement is such that, in the spark discharge gap 33, a spark discharge is carried out in a direction approximately parallel to a direction perpendicular to the axis CL1.
  • a distance along the axis CL1 between a point, on the other end face 32F of the ground electrode side tip 32, positioned closest to the rear end side in the direction of the axis CL1 and a point, on a surface of the center electrode side tip 31 opposed to the other end face 32F of the ground electrode side tip 32, positioned closest to the leading end side along the axis CL1 is taken to be A (mm)
  • a length of the other end face 32F of the ground electrode side tip 32 along the axis CL1 is taken to be B (mm)
  • a configuration is adopted such that 0.05 ⁇ A ⁇ B+0.2 and 0.3 ⁇ B ⁇ 0.7 are satisfied.
  • the distance between the center electrode side tip 31 and ground electrode side tip 32 is set so as to satisfy 0.4 ⁇ G ⁇ 1.0.
  • the area of the other end face 32F of the ground electrode side tip 32 is taken to be SX (mm 2 )
  • each of the width and thickness of the ground electrode side tip 32 is set so as to satisfy 0.3 ⁇ SX ⁇ 0.6 (for example, the ground electrode side tip 32 is such that the width thereof is set to 0.75mm or more and 0.85 or less, and the thickness thereof is set to 0.4mm or more and 0.7 or less).
  • an area SA1 (mm 2 ; in Fig. 5 , the region patterned with scattered points) to be described hereafter, shown in Fig. 5
  • an area SA2 (mm 2 ; in Fig. 6 , the region patterned with scattered points) to be described hereafter, shown in Fig.
  • the area SA1 refers to the area of a region AR1 bounded by a first tangent line TL1 drawn from one end of a side corresponding to the other end face 32F of the ground electrode side tip 32 to a projection region corresponding to the leading end face of the center electrode side tip 31, a second tangent line TL2 drawn from the other end of the side corresponding to the other end face 32F of the ground electrode side tip 32 to the projection region corresponding to the leading end face of the center electrode side tip 31, a projection line (the side) corresponding to the other end face 32F of the ground electrode side tip 32, and a projection line corresponding to the outer periphery of the leading end face of the center electrode side tip 31, as shown in Fig. 5 .
  • the area SA2 refers to the area of a region AR2 in which a projection region of the center electrode side tip 31 and a projection region of the ground electrode side tip 32 overlap, as shown in Fig. 6 .
  • a configuration is adopted such that the relative positions of the ground electrode side tip 32 and center electrode side tip 31 satisfy 0.12 ⁇ SA1 ⁇ SA2/G. Consequently, it is possible to suppress an increase in discharge voltage, and it is possible to more reliably prevent a spark discharge being generated between only small portions of the ground electrode side tip 32 and center electrode side tip 31, and the ground electrode side tip 32 and the like wearing out locally. As a result of this, it is possible to effectively improve wear resistance.
  • the distance B is set to 0.3mm or more, it is possible to achieve a suppression of overheating in the ground electrode side tip 32, or the like, and as the distance A is set to 0.05mm or more, it is possible to more reliably prevent uneven wear in an edge portion of the center electrode side tip 31 or ground electrode side tip 32. As a result of this, it is possible to achieve a further improvement in wear resistance.
  • the distance B is set to 0.7mm or less, it is possible to effectively suppress heat being removed from a flame kernel by the ground electrode side tip 32, or the like, and as the distance A is set to "B+0.2mm" or less, it is possible to cause a flame kernel to grow smoothly toward the central side of the combustion chamber. Because of this, it is possible to further improve ignitability.
  • the size G of the spark discharge gap 33 is set to 0.1mm or less, it is possible to more reliably suppress an increase in discharge voltage, and furthermore, as the area SX is set to 0.3mm 2 or more, it is possible to secure a still larger wear volume of the ground electrode side tip 32. Because of this, it is possible to achieve a further improvement in wear resistance.
  • the size G of the spark discharge gap 33 is set to 0.4mm or more, and the area SX is set to 0.6mm 2 or less, it is possible to more effectively suppress a flame kernel growth inhibition due to the ground electrode side tip 32 or the like, and it is possible to further improve ignitability.
  • the cross-sectional area SY is set to 3.5mm 2 or less, it is possible to more reliably prevent heat being removed from a flame kernel by the ground electrode 27, and as the width W is set to 2.2mm or less, it is possible to effectively suppress a flame kernel growth inhibition due to the ground electrode 27. Because of this, it is possible to achieve a further improvement in ignitability.
  • SI/SZ ⁇ 0.5 it is possible to secure a sufficient thickness of the outer layer 27Z, and it is possible to more reliably prevent damage to the outer layer 27Z induced by a thermal expansion of the inner layer 27I.
  • both side surfaces 27S1 and 27S2 of the ground electrode 27 are formed into a convexly curved surface, it becomes easier for a fuel gas becomes infiltrate into the spark discharge gap 33, and it is thus possible to further improve ignitability.
  • the ground electrode side tip 32 is joined to the leading end portion of the ground electrode 27, and the other end face 32F of the ground electrode side tip 32 is opposed to the side surface of the center electrode side tip 31.
  • a configuration is adopted such that the ground electrode side tip 32 is not provided, and another end face 37F of a ground electrode 37 is opposed to the side surface of the leading end portion of the center electrode 5 (the side surface of the center electrode side tip 31), as shown in Fig. 7 .
  • a spark discharge gap 43 is formed between the other end face 37F of the ground electrode 37 and the side surface of the leading end portion of the center electrode 5 (the side surface of the center electrode side tip 31).
  • a configuration is adopted such that an area SB1 (mm 2 ; in Fig. 8 , the region patterned with scattered points) to be described hereafter, shown in Fig. 8 , when the ground electrode 37 and the leading end face of the center electrode 5 (center electrode side tip 31) are projected, along the axis CL1, onto a virtual plane perpendicular to the axis CL1, an area SB2 (mm 2 ; in Fig. 9 , the region patterned with scattered points) to be described hereafter, shown in Fig.
  • the area SB1 refers to the area of a region AR3 bounded by a third tangent line TL3 drawn from one end of a side corresponding to the other end face 37F of the ground electrode 37 to a projection region corresponding to the leading end face of the center electrode 5 (center electrode side tip 31), a fourth tangent line TL4 drawn from the other end of the side corresponding to the other end face 37F of the ground electrode 37 to the projection region corresponding to the leading end face of the center electrode 5 (center electrode side tip 31), a projection line (the side) corresponding to the other end face 37F of the ground electrode 37, and a projection line corresponding to the outer periphery of the leading end face of the center electrode 5 (center electrode side tip 31), as shown in Fig. 8 .
  • the area SB2 refers to the area of a region AR4 in which a projection region of the center electrode 5 (center electrode side tip 31) and a projection region of the other end face 37F of the ground electrode 37 overlap, as shown in Fig. 9 .
  • spark plug samples wherein the ground electrode side tip is provided on the ground electrode, and the value of the expression SA1 ⁇ SA2/G (mm 3 ) is variously changed, are fabricated, and a desktop spark endurance test and flame kernel growth evaluation test are carried out on each sample. Then, test results of the individual samples are compared with test results when the tests are carried out on spark plug samples (samples in a comparison example; refer to Fig.
  • a ground electrode side tip (0.8mm in length) formed from an iridium alloy is provided on the opposite surface of the other end portion of the ground electrode, and the other end face of the ground electrode side tip is opposed to the leading end face of a center electrode side tip (0.5mm in length).
  • the outline of the desktop spark endurance test is as follows. That is, after mounting samples in a predetermined chamber, the pressure in the chamber is set to 1.6MPa, and each sample is discharged over 300 hours with the frequency of an applied voltage set to 100Hz (that is, at the rate of 6000 times per minute). Then, a spark plug gap size is measured after an elapse of 300 hours, and an increment (a gap increment) with respect to a spark discharge gap size (an initial gap size G) before the test (in an initial condition) is measured. It can be said that the smaller the gap increment, the more superior in terms of wear resistance.
  • the outline of the flame kernel growth evaluation test is as follows. That is, after mounting samples in a predetermined chamber, a predetermined voltage is applied to each sample, generating a spark discharge. Then, after an elapse of a predetermined time after the spark discharge, as well as a schlieren image in the center of the spark discharge gap and in the vicinity thereof being obtained, the obtained schlieren image is binarized using a predetermined threshold, and the area of a high-density portion (that is, the area of a postgrowth flame kernel) is measured. It can be said that the larger the area, the more superior in terms of ignitability.
  • Results of the two tests are shown in Table 1.
  • the outside diameter of the leading end face of the center electrode side tip, the width of the ground electrode side tip, the distance A, the length B, and the initial gap size G, in each sample are shown in Table 1 as reference. Also, each sample is such that the ground electrode is formed into a rectangular cross-sectional shape.
  • the outline of the ignitability evaluation test is as follows. That is, after mounting each sample on a four cylinder engine (N/A) of 1.6L displacement, an ignition timing is set to 60° BTDC, and the engine is operated at a rotation speed of 1600rpm. Then, while air/fuel ratios are being gradually increased (a fuel is being made thinner), an engine torque variation rate is measured for each air/fuel ratio, and an air/fuel ratio when the engine torque variation rate exceeds 5% is specified as a critical air/fuel ratio. This means that the higher the critical air/fuel ratio, the more superior in ignitability.
  • Results of the desktop spark endurance test are shown in Fig. 11
  • results of the ignitability evaluation test are shown in Fig. 12 .
  • test results of the samples with the distance B set to 0.1mm are indicated by circles
  • test results of the samples with the distance B set to 0.3mm are indicated by triangles
  • test results of the samples with the distance B set to 0.5mm are indicated by squares
  • test results of the samples with the distance B set to 0.7mm are indicated by diamonds.
  • test results of the samples with the distance B set to 0.9mm are indicated by cross marks.
  • each sample is such that 0.12 ⁇ SA1 ⁇ SA2/G(mm 3 ) ⁇ 0.49, 0.3 ⁇ SX(mm) ⁇ 0.6, and 0.4 ⁇ G(mm) ⁇ 1.0 are satisfied, and the ground electrode is formed into a rectangular cross-sectional shape.
  • the samples with the distance B set to less than 0.3mm are slightly inferior in wear resistance as the spark discharge gap is liable to increase. It is conceivable that this is because wear of the ground electrode side tip progresses quickly because the ground electrode side tip is overheated, or a sufficient wear volume cannot be secured. Also, it is confirmed that the samples with the distance A set to less than 0.05mm are also slightly inferior in wear resistance. It is conceivable that this is because spark discharges with the edge portion of each of the center electrode side tip and ground electrode side tip as a base point are concentrically generated.
  • the samples with the distance A set to 0.05mm or more and the distance B set to 0.3mm or more have superior wear resistance as the gap increment is less than 0.10mm. Furthermore, it is found that the samples with the distance A set to "B+0.2mm" or less and the distance B set to 0.7mm or less are superior in ignitability as the critical air/fuel ratio exceeds 20.
  • spark plug samples wherein the area SX(mm 2 ) of the other end face of the ground electrode side tip and the spark discharge gap size G are variously changed are fabricated, and the desktop spark endurance test and ignitability evaluation test are carried out on each sample. Results of the desktop spark endurance test are shown in Fig. 13 , and results of the ignitability evaluation test are shown in Fig. 14 . In Figs.
  • test results of the samples with the area SX set to 0.1mm 2 are indicated by circles
  • test results of the samples with the area SX set to 0.3mm 2 are indicated by triangles
  • test results of the samples with the area SX set to 0.6mm 2 are indicated by squares
  • test results of the samples with the area SX set to 0.9mm 2 are indicated by diamonds.
  • each sample is such that the distance A is set to 0.05mm, and the distance B is set to 0.3mm
  • each sample is such that the distance A is set to 0.9mm, and the distance B is set to 0.7mm.
  • each sample is configured in such a way as to satisfy 0.12 ⁇ SA1 ⁇ SA2/G(mm 3 ) ⁇ 0.49, and is such that the ground electrode is formed into a rectangular cross-sectional shape.
  • spark plug samples wherein a configuration is adopted such that the ground electrode side tip is not provided, and the other end face of the ground electrode is opposed to the side surface of the leading end portion of the center electrode, and the value of the expression SB1 ⁇ SB2/G is variously changed, are fabricated, and the desktop spark endurance test and flame kernel growth evaluation test are carried out on each sample. Results of both tests are shown in Table 2. The outside diameter of the leading end face of the center electrode side tip, the width of the ground electrode leading end, the distance A, and the initial gap size G, in each sample are shown in Table 2 as reference.
  • the outline of the thermal resistance test is as follows. That is, after mounting samples on an engine of SC17.6 (SAE J2203) of which the compression ratio is set to 5.6 and the ignition timing is set to 30° BTDC, a certain amount of supercharging is carried out while the engine is being operated at 2700rpm using a benzene-based fuel, and a fuel injection amount at which the temperature in the combustion chamber is highest is specified. Then, it is confirmed whether or not preignition occurs when the engine is operated at the specified fuel injection amount.
  • Results of the thermal resistance evaluation test are shown in Tables 3 and 4, and results of the ignitability evaluation test are shown in Fig. 15 .
  • Test results of samples wherein the cross-sectional area SY is changed after setting the width W to 1.8mm are shown in Table 3, and test results of samples wherein the width W is changed after setting the cross-sectional area SY to 2.3mm 2 are shown in Table 4. Also, in Fig.
  • test results of the samples with the cross-sectional area SY set to 2.1mm 2 are indicated by circles
  • test results of the samples with the cross-sectional area SY set to 2.3mm 2 are indicated by triangles
  • test results of the samples with the cross-sectional area SY set to 2.9mm 2 are indicated by squares
  • test results of the samples with the cross-sectional area SY set to 3.5mm 2 are indicated by diamonds
  • test results of the samples with the cross-sectional area SY set to 4.0mm 2 are indicated by cross marks.
  • Each sample is configured in such a way as to satisfy 0.12 ⁇ SA1 ⁇ SA2/G ⁇ 0.49, and is such that the ground electrode is formed into a rectangular cross-sectional shape.
  • the thickness of the ground electrode increases eventually by reducing the width, as a result of which the ground electrode takes a form in which it protrudes toward the combustion chamber center side which is higher in temperature, and the amount of heat received by the ground electrode increases.
  • the samples with the cross-sectional area SY set to 2.3mm 2 or more and 3.5mm 2 or less, and the width W set to 1.8mm or more and 2.2mm or less, are more superior in both ignitability and thermal resistance.
  • spark plug samples wherein SI/SZ is variously changed by increasing and reducing the cross-sectional area SI(mm 2 ) of the inner layer of the ground electrode and the cross-sectional area SZ (mm 2 ) of the ground electrode, on a cross section on which the cross-sectional area of the inner layer is largest in a direction perpendicular to the central axis of the ground electrode, are fabricated, and a desktop burner test and thermal resistance improvement value measurement test are carried out on each sample.
  • the outline of the desktop burner test is as follows. That is, each sample, after being heated by a burner for one minute in such a way that the temperature of the ground electrode reaches 1050°C in an ambient air atmosphere, is slowly cooled for one minute, and with this treatment as one cycle, 3000 cycles are implemented. Then, by observing the ground electrode after 3000 cycles are finished, the presence or absence of a crack in the outer layer induced by an expansion of the inner layer is confirmed. Results of the test are shown in Table 5.
  • the outline of the thermal resistance improvement value measurement test is as follows. That is, thermal values of spark plug samples wherein, after setting the cross-sectional area SY of the ground electrode to 2.3mm 2 , 2.6mm 2 , or 2.9mm 2 , the ground electrode is formed from an Ni alloy, without the inner layer being provided therein, are measured one for each of the cross-sectional areas SY. Then, each of thermal values of spark plug samples wherein, after setting the cross-sectional area SY of the ground electrode to 2.3mm 2 , 2.6mm 2 , or 2.9mm 2 , SI/SZ is variously changed, is measured, and improvement values of the thermal values with respect to thermal values of compared samples with the same cross-sectional area SY are measured.
  • test results of the samples with the cross-sectional area SY set to 2.3mm 2 are indicated by circles
  • test results of the samples with the cross-sectional area SY set to 2.6mm 2 are indicated by triangles
  • test results of the samples with the cross-sectional area SY set to 2.9mm 2 are indicated by squares.
  • thermal values are measured in the following way. That is, after mounting samples on an engine of SC17.6 (SAE J2203) of which the compression ratio is set to 5.6, and the ignition timing is set to 30° BTDC, a certain amount of supercharging is carried out while the engine is being operated at a rotation speed of 2700rpm using a benzene-based fuel, and a fuel injection amount is adjusted to one at which the temperature of the combustion chamber is highest at the supercharging amount. An increase of the supercharging amount and the adjustment of the fuel injection amount are repeatedly carried out, and a supercharging pressure immediately before preignition (premature ignition) occurs is specified.
  • spark plug samples wherein the ground electrode is formed into a rectangular cross-sectional shape, and spark plug samples wherein the side surface of the ground electrode is formed into a curved shape convex outward, and a curvature radius R of the side surface is set to 1.2mm, 1.5mm, or 1.8mm, are fabricated.
  • the ignitability evaluation test (the ignition timing is changed from 60° BTDC to 70° BTDC) is carried out, and a critical air/fuel ratio in each relative position is measured.
  • a range in which the critical air/fuel ratio fluctuates accompanying a change of the relative position in each sample is shown in Fig. 17 .

Landscapes

  • Spark Plugs (AREA)
  • Ignition Installations For Internal Combustion Engines (AREA)

Claims (4)

  1. Bougie (1) comprenant : un corps isolant (2) comportant un trou axial (4) passant à travers celui-ci dans une direction d'un axe (CL1) ; une électrode centrale (5) insérée dans le trou axial (4) ; une enveloppe métallique (3) prévue sur une périphérie extérieure du corps isolant (2) ; une électrode de masse (27) fixée à une partie d'extrémité avant de l'enveloppe métallique (3) ; et une extrémité côté électrode de masse (32), formée à partir d'un métal contenant un métal noble, dont au moins une partie d'extrémité est jointe à une partie d'extrémité avant de l'électrode de masse (27), l'électrode centrale (5) comportant, au niveau de sa partie d'extrémité avant, une extrémité côté électrode centrale (31) formée à partir d'un métal contenant un métal noble, une autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32) étant face à une surface latérale de l'extrémité côté électrode centrale (31), et un espace (33) étant formé entre l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32) et la surface latérale de l'extrémité côté électrode centrale (31),
    caractérisée en ce que
    lorsqu'une aire d'une région, dans un plan de projection dans lequel l'extrémité côté électrode de masse (32) et une face d'extrémité avant de l'extrémité côté électrode centrale (31) sont projetées dans un plan virtuel perpendiculaire à l'axe (CL1), délimité par une première tangente (TL1) tracée à partir d'une extrémité d'un côté correspondant à l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32) jusqu'à une région de projection correspondant à la face d'extrémité avant de l'extrémité côté électrode centrale (31), une deuxième tangente (TL2) tracée à partir de l'autre extrémité du côté correspondant à l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32) jusqu'à la région de projection correspondant à la face d'extrémité avant de l'extrémité côté électrode centrale (31), une droite de projection correspondant à l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32), et une droite de projection correspondant à la périphérie extérieure de la face d'extrémité avant de l'extrémité côté électrode centrale (31), est désignée par SA1 (mm2),
    lorsqu'une aire d'une région, dans laquelle une région de projection de l'extrémité côté électrode centrale (31) et une région de projection de l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32) se superposent lorsque l'extrémité côté électrode centrale (31) et l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32) sont projetées dans un plan virtuel parallèle à l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32), est désignée par SA2 (mm2), et
    lorsque la taille de l'espace (33) est désignée par G (mm),
    0,12 ≤ SA1 x SA2/G (mm3) ≤ 0,49 est satisfait,
    lorsqu'une distance le long de l'axe (CL1) entre un point, sur l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32), positionné le plus près d'un côté d'extrémité arrière dans la direction de l'axe (CL1), et un point, sur une surface de l'extrémité côté électrode centrale (31) face à l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32), positionné le plus près du côté d'extrémité avant le long de l'axe (CL1), est désignée par A (mm), et
    lorsqu'une longueur le long de l'axe (CL1) de l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32) est désignée par B (mm),
    0,05 ≤ A ≤ B + 0,2 et 0,3 ≤ B ≤ 0,7 sont satisfaits, et
    lorsque l'aire de l'autre face d'extrémité (32F) de l'extrémité côté électrode de masse (32) est désignée par SX (mm2),
    0,3 ≤ SX ≤ 0,6 et 0,4 ≤ G ≤ 1,0 sont satisfaits.
  2. Bougie (1) selon la revendication 1, caractérisée en ce que lorsqu'une section transversale de l'électrode de masse (27) est désignée par SY (mm2), et lorsque la largeur de l'électrode de masse (27) est désignée par W (mm), sur n'importe quelle section transversale, d'une partie du centre longitudinal à ladite extrémité de l'électrode de masse (27), dans une direction perpendiculaire à un axe central (CL2) de l'électrode de masse (27),
    2,3 ≤ SY ≤ 3,5 et 1,8 ≤ W ≤ 2,2 sont satisfaits.
  3. Bougie (1) selon l'une quelconque des revendications 1 et 2, caractérisée en ce que
    l'électrode de masse (27) comprend une couche extérieure (27Z) et une couche intérieure (271), prévue à l'intérieur de la couche extérieure (27Z), qui est formée à partir d'un métal avec une meilleure conductivité thermique que la couche extérieure (27Z), et
    lorsqu'une section transversale de la couche intérieure (271) est désignée par SI (mm2), et lorsque la section transversale de l'électrode de masse (27) est désignée par SZ (mm2), sur une section transversale sur laquelle la section transversale de la couche intérieure (271) est la plus grande dans une direction perpendiculaire à l'axe central (CL2) de l'électrode de masse (27),
    0,2 ≤ SI/SZ ≤ 0,5 est satisfait.
  4. Bougie (1) selon l'une quelconque des revendications 1 à 3, caractérisée en ce que
    les deux surfaces latérales (27S1 et 27S2) de l'électrode de masse (27) adjacentes à une surface (27T) opposée de l'électrode de masse (27) face à l'électrode centrale (5) réalisent une forme incurvée convexe vers l'extérieur, et
    lorsque les rayons de courbure des lignes externes des deux surfaces latérales (27S1 et 27S2) sont désignés par R (mm) sur une section transversale perpendiculaire à l'axe central (CL2) de l'électrode de masse (27),
    R ≤ 1,5 est satisfait.
EP12151260.2A 2011-01-17 2012-01-16 Bougie d'allumage Active EP2477286B1 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2011006987 2011-01-17

Publications (3)

Publication Number Publication Date
EP2477286A2 EP2477286A2 (fr) 2012-07-18
EP2477286A3 EP2477286A3 (fr) 2014-04-30
EP2477286B1 true EP2477286B1 (fr) 2017-10-18

Family

ID=45655147

Family Applications (1)

Application Number Title Priority Date Filing Date
EP12151260.2A Active EP2477286B1 (fr) 2011-01-17 2012-01-16 Bougie d'allumage

Country Status (2)

Country Link
EP (1) EP2477286B1 (fr)
JP (1) JP5622991B2 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5789276B2 (ja) * 2013-02-14 2015-10-07 日本特殊陶業株式会社 点火システム
JP6230348B2 (ja) * 2013-09-13 2017-11-15 日本特殊陶業株式会社 スパークプラグ
US10666023B2 (en) * 2018-07-03 2020-05-26 Ngk Spark Plug Co., Ltd. Spark plug
DE112020002185T5 (de) 2019-04-30 2022-04-07 Federal-Mogul Ignition Llc Zündkerzenelektrode und verfahren zur herstellung derselben
CN115064938B (zh) * 2022-05-19 2023-05-23 重庆长安汽车股份有限公司 一种火花塞性能的测试系统及测试的方法

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61171080A (ja) * 1985-01-24 1986-08-01 日本特殊陶業株式会社 点火プラグ
JPH11121142A (ja) * 1997-10-20 1999-04-30 Ngk Spark Plug Co Ltd 多極スパークプラグ
JP2000208234A (ja) * 1998-11-09 2000-07-28 Ngk Spark Plug Co Ltd スパ―クプラグ及びそのスパ―クプラグを用いた点火システム
JP2006236906A (ja) 2005-02-28 2006-09-07 Ngk Spark Plug Co Ltd スパークプラグの製造方法
JP4913716B2 (ja) 2007-12-19 2012-04-11 日本特殊陶業株式会社 スパークプラグ
JP5028299B2 (ja) * 2008-02-25 2012-09-19 日本特殊陶業株式会社 スパークプラグ
JP4864065B2 (ja) * 2008-11-05 2012-01-25 日本特殊陶業株式会社 スパークプラグ

Non-Patent Citations (1)

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

Also Published As

Publication number Publication date
JP5622991B2 (ja) 2014-11-12
EP2477286A2 (fr) 2012-07-18
EP2477286A3 (fr) 2014-04-30
JP2012164644A (ja) 2012-08-30

Similar Documents

Publication Publication Date Title
EP2214274B1 (fr) Bougie d'allumage pour moteur à combustion interne et procédé de fabrication de bougie d'allumage
EP2234226B1 (fr) Bougie d'allumage pour moteur à combustion interne et son procédé de fabrication
EP2333918B1 (fr) Bougie pour moteur a combustion interne
EP2477286B1 (fr) Bougie d'allumage
EP2133967B1 (fr) Bougie d'allumage
EP2192661B1 (fr) Bougie d'allumage
EP2020713B1 (fr) Bougie pour moteur à combustion interne et son procédé de fabrication
EP2597737B1 (fr) Bougie d'allumage
EP2381547A1 (fr) Bougie d'allumage à jet de plasma
JP2007287667A (ja) 内燃機関用スパークプラグ
KR101508784B1 (ko) 내연 엔진용 스파크 플러그
EP1837964B1 (fr) Bougie d'allumage à utiliser dans un moteur à combustion interne
CN104253377B (zh) 火花塞
EP2264844B1 (fr) Bougie d'allumage pour un moteur a combustion interne
EP2405542B1 (fr) Bougie d'allumage de jet de plasma
US10530132B2 (en) Spark plug for internal combustion engine and method for manufacturing the same
EP2493037A2 (fr) Bougie d'allumage de jet de plasma
EP3252891B1 (fr) Bougie d'allumage
US8704434B2 (en) Spark plug and method of manufacturing the same
JP2007134319A (ja) スパークプラグ
CN104242060B (zh) 火花塞
EP3065238B1 (fr) Bougie d'allumage
EP3001520B1 (fr) Bougie d'allumage
US9660424B2 (en) Spark plug
JP2009151996A (ja) 内燃機関用スパークプラグ

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

AK Designated contracting states

Kind code of ref document: A2

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

AX Request for extension of the european patent

Extension state: BA ME

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: NGK SPARK PLUG CO., LTD.

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

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

AX Request for extension of the european patent

Extension state: BA ME

RIC1 Information provided on ipc code assigned before grant

Ipc: H01T 13/39 20060101ALI20140324BHEP

Ipc: H01T 13/20 20060101AFI20140324BHEP

Ipc: H01T 13/16 20060101ALI20140324BHEP

17P Request for examination filed

Effective date: 20141015

RBV Designated contracting states (corrected)

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

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

INTG Intention to grant announced

Effective date: 20170621

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

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 938717

Country of ref document: AT

Kind code of ref document: T

Effective date: 20171115

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602012038582

Country of ref document: DE

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: NL

Ref legal event code: MP

Effective date: 20171018

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG4D

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 938717

Country of ref document: AT

Kind code of ref document: T

Effective date: 20171018

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: 20171018

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

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: 20171018

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: 20171018

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: 20180118

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: 20171018

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: 20171018

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

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: 20171018

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: 20180119

Ref country code: AT

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: 20171018

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: 20171018

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: 20171018

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: 20180218

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: 20180118

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602012038582

Country of ref document: DE

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

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: 20171018

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: 20171018

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: 20171018

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: 20171018

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: 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: 20171018

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: 20171018

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: 20171018

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: 20171018

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

26N No opposition filed

Effective date: 20180719

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

Effective date: 20180118

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: 20180116

REG Reference to a national code

Ref country code: IE

Ref legal event code: MM4A

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20180131

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: 20180118

Ref country code: LI

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

Effective date: 20180131

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: 20171018

Ref country code: CH

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

Effective date: 20180131

Ref country code: BE

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

Effective date: 20180131

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: 20180116

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

Ref country code: FR

Payment date: 20181213

Year of fee payment: 8

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

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: 20171018

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 NON-PAYMENT OF DUE FEES

Effective date: 20180116

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: 20171018

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: 20120116

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: 20171018

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 FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20171018

Ref country code: MK

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

Effective date: 20171018

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: 20171018

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

Ref country code: FR

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

Effective date: 20200131

P01 Opt-out of the competence of the unified patent court (upc) registered

Effective date: 20230512

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 602012038582

Country of ref document: DE

Owner name: NITERRA CO., LTD., NAGOYA-SHI, JP

Free format text: FORMER OWNER: NGK SPARK PLUG CO., LTD., NAGOYA-SHI, AICHI, JP

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

Ref country code: DE

Payment date: 20231128

Year of fee payment: 13