Ignition apparatus including spark plug that generates plasma

    公开(公告)号:US11129268B2

    公开(公告)日:2021-09-21

    申请号:US15914101

    申请日:2018-03-07

    摘要: An ignition apparatus is provided which ignites a mixture of air and fuel gas by plasma to generate an initial flame. The apparatus includes: a spark plug that includes an inner conductor, a cylindrical outer conductor that holds the inner conductor thereinside, and a dielectric that is provided between the inner conductor and the outer conductor, and that generates plasma in a plasma formation space between the inner conductor and the outer conductor; an electromagnetic wave power supply that generates an electromagnetic wave to apply electromagnetic wave power to the spark plug; an evaluation section that evaluates a state of formation of the plasma; a determination section that determines a matching object of the electromagnetic wave based on an evaluation result by the evaluation section; and a coupled state control section that controls a matching condition of the electromagnetic wave so that the electromagnetic wave matches the matching object.

    Ignition device
    2.
    发明授权

    公开(公告)号:US10772184B2

    公开(公告)日:2020-09-08

    申请号:US16565910

    申请日:2019-09-10

    摘要: An ignition device ignites a mixture of air and fuel gas by plasma to generate an initial flame. The ignition device includes a spark plug having an inner conductor, a cylindrical outer conductor that holds the inner conductor inside, and a dielectric provided between the inner conductor and the outer conductor, and the spark plug configured to emit an electromagnetic wave to a plasma formation space between the inner conductor and the outer conductor to generate a plasma. The ignition device includes an electromagnetic wave power supply that generates the electromagnetic wave by inputting the electromagnetic wave power Ps to the spark plug and a power supply control unit that controls the electromagnetic wave power supply. The electromagnetic wave power supply is configured to generate high frequency power at a number of different frequencies. The power supply control unit outputs at least one of the plurality of high frequency powers generated by the electromagnetic wave power supply as the electromagnetic wave power.

    Ignition apparatus
    3.
    发明授权

    公开(公告)号:US11181090B2

    公开(公告)日:2021-11-23

    申请号:US16007174

    申请日:2018-06-13

    摘要: In an ignition apparatus, an ignition plug is provided. In the ignition plug, a tubular outer conductor surrounds an inner conductor, and a dielectric member is disposed in the tubular outer conductor to define a plasma formation region between the inner conductor and the dielectric member. The plasma formation region has opposing first and second ends in the axial direction of the tubular outer conductor, and the first end of the plasma formation region communicates with the combustion chamber. A power source is connected between the inner and tubular outer conductors. A controller causes a power source to apply electromagnetic power pulses with intervals therebetween across the inner and tubular outer conductors during an ignition cycle of an engine. Each of the electromagnetic power pulses forms at least a corresponding plasma in the plasma formation region.

    IGNITION APPARATUS
    4.
    发明申请
    IGNITION APPARATUS 审中-公开

    公开(公告)号:US20180363618A1

    公开(公告)日:2018-12-20

    申请号:US16007174

    申请日:2018-06-13

    IPC分类号: F02P9/00 F02P23/04

    摘要: In an ignition apparatus, an ignition plug is provided. In the ignition plug, a tubular outer conductor surrounds an inner conductor, and a dielectric member is disposed in the tubular outer conductor to define a plasma formation region between the inner conductor and the dielectric member. The plasma formation region has opposing first and second ends in the axial direction of the tubular outer conductor, and the first end of the plasma formation region communicates with the combustion chamber. A power source is connected between the inner and tubular outer conductors. A controller causes a power source to apply electromagnetic power pulses with intervals therebetween across the inner and tubular outer conductors during an ignition cycle of an engine. Each of the electromagnetic power pulses forms at least a corresponding plasma in the plasma formation region.

    Spark plug for internal combustion engine

    公开(公告)号:US10886708B2

    公开(公告)日:2021-01-05

    申请号:US16584998

    申请日:2019-09-27

    申请人: DENSO CORPORATION

    IPC分类号: H01T13/32 H01T13/52

    摘要: A spark plug has a tubular ground electrode, an insulator, and a center electrode. The insulator has an insulator protruding portion protruding to a tip end side in a plug axial direction with respect to the ground electrode. The center electrode 4 has an exposed portion exposed through a tip end of the insulator protruding portion. The exposed portion of the center electrode has a first part covering the insulator protruding portion from the tip end side in the plug axial direction, and a second part extending from the first part to a base end side in the plug axial direction and covering the entire circumference of an outer peripheral surface of the insulator protruding portion from an outer peripheral side in a plug radial direction.

    Ignition control apparatus
    6.
    发明授权

    公开(公告)号:US10697419B2

    公开(公告)日:2020-06-30

    申请号:US16079120

    申请日:2017-02-13

    申请人: DENSO CORPORATION

    摘要: An ignition control apparatus applied to an internal combustion engine including a spark plug includes an in-cylinder pressure acquisition section, a frequency signal transmitting section which transmits a frequency signal having a predetermined frequency to a switching element, and a weak discharge generating section which causes the frequency signal to be transmitted during an intake stroke and controls the frequency signal such that a weak discharge is generated at the spark plug a plurality of times. The weak discharge generating section controls the frequency signal so as to cause a duty ratio of the switching element to be changed in accordance with the in-cylinder pressure, such that the frequency of generating weak discharges during a time period in which the frequency signal is transmitted becomes higher than a predetermined frequency.

    Ignition apparatus for internal combustion engine

    公开(公告)号:US10833487B2

    公开(公告)日:2020-11-10

    申请号:US16454510

    申请日:2019-06-27

    申请人: DENSO CORPORATION

    IPC分类号: H01T13/34 H01T13/08

    摘要: An ignition apparatus for an internal combustion engine includes a center electrode, a ground electrode, an insulator, a housing, and an insulator protective wall portion. The ground electrode is disposed such that a discharge gap is formed between the ground electrode and the center electrode. The insulator holds the center electrode on an inner side of the insulator. The housing holds the insulator on an inner side of the housing. The insulator protective wall portion is arranged to surround an outer circumference side of a distal end portion of the insulator. A distal end of the insulator protective wall portion is positioned further towards a distal end side than a distal end of the insulator is and further towards a proximal end side than a distal end of the center electrode is. The insulator protective wall portion includes an inward protruding portion that protrudes towards a side surface of the center electrode.

    Spark plug for internal combustion engine

    公开(公告)号:US10454252B2

    公开(公告)日:2019-10-22

    申请号:US16143857

    申请日:2018-09-27

    申请人: DENSO CORPORATION

    IPC分类号: H01T13/32 H01T13/04 H01T13/38

    摘要: A spark plug for an internal combustion engine is provided which has a center electrode and a ground electrode. The ground electrode includes an upright portion extending in a lengthwise direction of the spark plug and an extension bent from the upright portion in a radial direction of the spark plug. The extension has a slant surface which is shaped to be inclined away from the center electrode downstream in a flow of air-fuel mixture within a combustion chamber when the spark plug is mounted in the engine. This results in an increase in in distance by which a starting point on the ground electrode where a spark is created is moved on the slant surface, thereby increasing a length of time the spark is moved downstream and then blown out to increase the probability of successful ignition of the air-fuel mixture.

    Spark plug for internal combustion engines

    公开(公告)号:US10951011B2

    公开(公告)日:2021-03-16

    申请号:US16912751

    申请日:2020-06-26

    申请人: DENSO CORPORATION

    IPC分类号: H01T13/32

    摘要: A spark plug includes a housing, an insulator, a center electrode, and an earth electrode. The earth electrode has a gap-forming surface which forms a discharge gap between the gap-forming surface and a tip surface of the center electrode. The insulator includes an insulator protrusion protruding on the tip side of the housing in a plug axial direction. At least one of cross-sections passing through a plug center axis and parallel to the plug axial direction is referred to as an axial parallel cross-section. The outer peripheral surface of the insulator protrusion includes an insulator inclined surface extending inward toward the tip in the plug axial direction, in a straight line or a curve that is convex inward, in the axial parallel cross-section. In the axial parallel cross-section, a virtual straight line passing through both ends of the insulator inclined surface passes through the gap-forming surface.