Denso Corporation

Mitsunobu Niwa

Eiichi Kurokawa

Satoshi Hada

Shunichi Takeda

Hisaharu Morita

Toshiyuki Suzuki

Haruo Kawakita

An ignition control device includes a main ignition circuit to generate a spark discharge to a spark plug by controlling energization of a primary coil of an ignition coil for an internal combustion engine, an energy supply circuit that supplies energy based on a discharge continuation signal by controlling the energization of the primary coil during the spark discharge started by the operation of the main ignition circuit to supply a secondary current in the same direction as a main ignition continuously in a secondary coil of the ignition coil, a secondary current command circuit for outputting a command value of the secondary current based on the secondary current command signal, and an ignition control unit for setting signal values of the secondary current command signal and the discharge continuation signal.

Ignition control device

An ignition device includes a secondary current control circuit that receives a secondary current control signal IGa from an ECU, and a feedback circuit outputs a control signal for controlling energization of an primary coil to an energy supply circuit according to a result of comparison of a control value of the secondary current outputted from the secondary current control circuit and a detected value of the secondary current. Further, the ECU outputs a secondary current control signal IGa in accordance with engine parameters. Thereby, the secondary current substantially indicating the amount of energy that is supplied into the ignition coil from the energy supply circuit can be controlled in accordance with the operating condition of the engine. Therefore, it is possible to suppress excess or shortage of energy supplied from the energy supply circuit to an ignition coil from occurring.

Ignition device and ignition system

An ignition coil includes a coil portion and an igniter. The coil portion has a primary coil, a secondary coil, and a coil case. The primary coil and the secondary coil are disposed in the coil case. The igniter is disposed on one end side of the coil portion. The igniter includes a metallic frame connected to a voltage source at a constant potential, and a semiconductor integrated chip disposed on the metallic frame. The semiconductor integrated chip has a control circuit for controlling a switching element. The control circuit is formed by a dielectric isolation method. A surface of the semiconductor integrated chip on a silicon substrate-side is opposed to the metallic frame.

Ignition coil

The present invention relates a gas concentration detecting apparatus capable of appropriately making a decision on activation of each of a pump cell, a monitor cell and a sensor cell of its gas concentration sensor. In the apparatus, a control circuit outputs an oxygen concentration value on the basis of a current flowing when a voltage is applied to the pump cell and outputs an NOx concentration value on the basis of a current flowing at the voltage application to the sensor cell. Moreover, the control circuit separately makes a decision on activation of the pump cell and a decision on activation of the sensor cell in the middle of the activation of the sensor. Still moreover, the control circuit makes the decision on the activation of the sensor cell after the activation of the pump cell reaches completion.

Gas concentration detecting apparatus

A noiseless circuit structure of a gas concentration measuring apparatus is provided. The gas concentration measuring apparatus includes a control circuit and a gas sensor including a solid electrolyte body, a cell, and a heater serving to heat the solid electrolyte body up to an activation temperature. The control circuit is designed to cancel or remove electric noises arising from an on-off operation of the heater added to a sensor output.

Noiseless gas concentration measurement apparatus

A heater control system is provided for controlling the temperature of a heater used to heat a solid electrolyte-made sensor element of a gas concentration sensor up to a given temperature at which the sensor element is activated to provide a correct gas concentration output for controlling a preselected variable used in, for example, an automotive air-fuel ratio control system. The heater control system measures a resistance value of the sensor element and controls an electric power supplied to the heater as a function of the resistance value. The heater control system is designed to determine a controlled variable properly used to control the heater, thereby resulting in improved controllability of a power supply to the heater and also works to minimize an error in determining the resistance of the heater.

Power supply control system for heater used in gas sensor

A gas concentration measuring apparatus is provided which includes a gas concentration sensor consisting of a pump cell, a sensor cell, and a monitor cell. The pump cell works to determine the concentration of O . The sensor cell works to decompose an oxygen containing gas such as NOx and provide an output indicative of the concentration of NOx. The apparatus also includes an applying voltage determining circuit which looks up a predetermined voltage-to-current relation to determine a target voltage to be applied to the pump cell as a function of the current produced by the pump cell so as to preclude the pump cell from decomposing the oxygen containing gas component, thereby minimizing an error in determining the concentration of oxygen containing gas as a function of the output of the sensor cell.

Growing community of inventors

Kariya, Japan

Mitsunobu Niwa