Abstract: An ignition system includes a primary coil, a secondary coil, a first switch, a second switch, a third switch, a diode, and a switch control section. In the primary coil, a power supply is connected to a contact point between a first winding and a second winding. The secondary coil is magnetically coupled to the primary coil. The first switch is connected in series with the first winding. The second switch is connected in series with the second winding on the opposite side from the contact point. The third switch is connected in series with the second switch. The diode includes an anode connected between the second switch and the third switch and a cathode connected to the contact point. The switch control section controls opening and closing of each switch.

Abstract: An ignition device includes: a primary coil including a first winding and a second winding connected in series to the first winding; a secondary coil connected to a spark plug and magnetically coupled to the primary coil; a first switch that opens or closes the electrical path between the first terminal and the ground; a second switch that opens or closes the electrical path between the power source and the second terminal; a third switch that opens or closes the electrical path between the power source and the connection point; a fourth switch that opens or closes the electrical path between the second terminal and the ground; and a switch control unit that controls the opening and closing of each switch to open or close each electrical path.

Abstract: An ignition device includes: a primary coil including a first winding and a second winding connected in series to the first winding; a secondary coil connected to a spark plug and magnetically coupled to the primary coil; a first switch that opens or closes the electrical path between the first terminal and the ground; a second switch that opens or closes the electrical path between the power source and the second terminal; a third switch that opens or closes the electrical path between the power source and the connection point; a fourth switch that opens or closes the electrical path between the second terminal and the ground; and a switch control unit that controls the opening and closing of each switch to open or close each electrical path.

Abstract: An ignition system includes a primary coil, a secondary coil, a first switch, a second switch, a third switch, a diode, and a switch control section. In the primary coil, a power supply is connected to a contact point between a first winding and a second winding. The secondary coil is magnetically coupled to the primary coil. The first switch is connected in series with the first winding. The second switch is connected in series with the second winding on the opposite side from the contact point. The third switch is connected in series with the second switch. The diode includes an anode connected between the second switch and the third switch and a cathode connected to the contact point. The switch control section controls opening and closing of each switch.

Abstract: A circuit fixing member is provided which achieves a connection with a controlled object after a circuit module is produced, thereby avoiding disconnection of a wire member in the course of the production, easy to transfer between production processes, and is designed to avoid the entry of water into the circuit module. The terminal-embedded portion 110 of the circuit fixing member 10 which retains the control circuit 15 is equipped with a plurality of circuit supports 111 and the space 115 which communicates at an end thereof with the opened terminal insertion hole 117 and is closed at the other end thereof. For engaging the terminal fitting portion 130 of the terminal member 13 with the fitting portion 200 of the controlled object side terminal member 20 within the space 115, the terminal locking opening 114 and the terminal locking member 14 are provided. The terminal locking member 14 works to secure the locked portion 201 in the space 115.

Abstract: A circuit fixing member is provided which achieves a connection with a controlled object after a circuit module is produced, thereby avoiding disconnection of a wire member in the course of the production, easy to transfer between production processes, and is designed to avoid the entry of water into the circuit module. The terminal-embedded portion 110 of the circuit fixing member 10 which retains the control circuit 15 is equipped with a plurality of circuit supports 111 and the space 115 which communicates at an end thereof with the opened terminal insertion hole 117 and is closed at the other end thereof. For engaging the terminal fitting portion 130 of the terminal member 13 with the fitting portion 200 of the controlled object side terminal member 20 within the space 115, the terminal locking opening 114 and the terminal locking member 14 are provided. The terminal locking member 14 works to secure the locked portion 201 in the space 115.

Abstract: When an ECU applies to an igniter a plurality of pulse signals, the duty ratio of which is lower than a predetermined duty ratio, as a lock release signal, a latch circuit of a lock inhibition circuit stops applying a shut-off signal to a shut-off circuit thereby to release a lock condition of an IGBT. A drive main circuit thus restarts current supply to the IGBT. A condition detection circuit outputs to the ECU a condition signal corresponding to the current supplied while the IGBT is turned on.

Abstract: When an ECU applies to an igniter a plurality of pulse signals, the duty ratio of which is lower than a predetermined duty ratio, as a lock release signal, a latch circuit of a lock inhibition circuit stops applying a shut-off signal to a shut-off circuit thereby to release a lock condition of an IGBT. A drive main circuit thus restarts current supply to the IGBT. A condition detection circuit outputs to the ECU a condition signal corresponding to the current supplied while the IGBT is turned on.