An ignition coil for internal combustion engines is provided which includes a primary coil, a secondary coil, a case, a high-voltage terminal, a resistor, and a filled resin. The case has a case body and a high-voltage terminal extending downward from the case body. The high-voltage terminal is press-fit in the high-voltage tower to close the inside thereof. The resistor is fit in the high-voltage terminal. The high-voltage terminal includes a pressed wall and a non-pressed wall. The pressed wall is pressed against the high-voltage tower. The non-pressed wall is not pressed against the high-voltage tower. The resistor is fit in the non-pressed wall. This structure minimizes pressure exerted on the resistor and the high-voltage tower to secure a desired degree of durability of the resistor and the high-voltage tower.

An ignition coil for an internal combustion engine is provided which includes a case, a connector, a resinous member, and a retainer. The case is equipped with an opening portion and has component parts mounted therein. The connector is electrically connected to an external device. The resinous member is disposed in the case. The retainer firmly hold an external connecting member joined to the connector. The retainer is mechanically discrete from the case and secured to an attachment wall of the case. The attachment wall is defined by at least one of a wall of the case which constitutes the opening portion and a wall secured to the opening portion. The retainer has a portion embedded in the resinous member. This structure minimizes fretting wear between terminals of the connector and the external connecting member such as a wire harness.

An ignition device includes: a high frequency power source; a first device having inductance; a second device having capacitance; a discharge GAP; and a shield device which covers a connection portion between the first device and the second device, and is connected to the ground. The high frequency power source supplies AC power to the discharge GAP by using a resonance circuit composed of the first device and the second device, and ignites fuel by discharge plasma generated in the discharge GAP. In the ignition device, the first device, the second device, the connection portion, and the shield device are arranged in the same package and are sealed with an insulating substance.

Provided is an igniter capable of reducing occurrence of malfunction due to noise. An igniter (100) includes a switch element (111) having a first end, a temperature sensor (112) including at least one diode and having a cathode end (112B), a switch element control device (12) configured to control the switch element, and a switch element electrode (Pe) connected to the first end of the switch element and to the cathode end, and the switch element control device has a ground electrode (Pgnd) electrically isolated from the cathode end.

A plug connector capable of increasing the sealing between a rubber member and an outer circumferential surface of a spark plug insulator for improvement in current leakage resistance. The plug connector includes a conductive part that electrically connects a spark plug and a power supply member for power supply to the spark plug; and a rubber member that covers the conductive part. The spark plug has an insulator and a terminal electrode protruding toward the rear from a rear end of the insulator. The plug connector further includes a ring member arranged on an outer circumference of the rubber member.

An ignition coil for internal combustion engines is provided which includes a primary and a secondary coils magnetically coupled with each other, a case, a resistor, and a resinous filler. The case includes a case body in which the primary and secondary coils are disposed and a tubular high-voltage tower extending from the case body toward a head of the ignition coil. The resistor 3 is press-fitted into the high-voltage tower and electrically connected to the secondary coil. The resinous filler is packed in the case body to hermetically seal the primary coil and the secondary coil. The resistor includes a resinous coating which covers an outer circumference of the resistor and is press-fit in the high-voltage tower through the resinous coating. This facilitates hermetically sealing a gap between the resistor body and the case and ensures the stability of the sealing.

A corona ignition system for igniting fuel in a combustion chamber of an internal combustion engine, comprising a oscillating circuit, which contains an ignition electrode, a high-frequency generator, which is connected to the oscillating circuit, in order to produce an AC voltage to excite the oscillating circuit, a converter in order to produce an input voltage for the high-frequency generator from an on-board supply voltage, a voltage controller to stabilize the input voltage produced by the converter for the high-frequency generator, and a control unit for controlling the high-frequency generator, wherein the control unit communicates an imminent load change of the converter to the voltage regulator, before the load change occurs as a result of activation or deactivation of the high-frequency generator. A method for controlling a corona ignition system is also described.

To reduce the amount of exhausted unburned fuel and further improve fuel efficiency of an internal combustion engine 10 provided with an ignition device 12 that ignites fuel air mixture more forcefully than a spark discharge in a combustion chamber 20. The internal combustion engine 10 includes an internal combustion engine main body 11 formed with the combustion chamber 20 and the ignition device 12 that ignites the fuel air mixture more forcefully than the spark discharge in the combustion chamber 20. In addition, the internal combustion engine 10 includes an electromagnetic wave emission device 13 that emits an electromagnetic wave supplied from an electromagnetic wave oscillator 32 from an antenna 41. The electromagnetic wave emission device 13 emits the electromagnetic wave from the antenna 41, thereby creating an electric field for accelerating a propagation speed of a flame.

An apparatus operates at least one light-emitting diode in the form of a laser diode. The light-emitting diode is interconnected in series with the load section of a controllable semiconductor element and a current measuring resistor between a first supply voltage terminal and a second supply voltage terminal. The supply voltage terminals are the output connections of a voltage-regulating circuit in the form of a DC voltage boost converter which provides a supply voltage), and wherein a current-regulating circuit is provided for the current through the at least one light-emitting diode, whose actuator is the controllable semiconductor element.

A plug connector capable of increasing the sealing between a rubber member and an outer circumferential surface of a spark plug insulator for improvement in current leakage resistance. The plug connector includes a conductive part that electrically connects a spark plug and a power supply member for power supply to the spark plug; and a rubber member that covers the conductive part. The spark plug has an insulator and a terminal electrode protruding toward the rear from a rear end of the insulator. The plug connector further includes a ring member arranged on an outer circumference of the rubber member.