Yamaha Hatsudoki Kabushiki Kaisha

Tokyo Electric Co.

Akira Yamada

Miyoshi Ishibashi

Takumori Yoshida

Shunji Akitsu

Sadayuki Shinmura

Shuichi Suzuki

The present invention relates to ignition systems for internal combustion engines and, in particular, to a spark ignition system specifically adapted for two-cycle engines. An ignition system is provided which is able to avoid ignition plug smolder and electrode contamination by providing for self-cleaning of the ignition plug electrodes and ensuring complete combustion of an injected rich mixture of fuel/air in the vicinity of the ignition plug electrodes within a combustion chamber. This is accomplished by employing two distinct, yet interrelated, ignition plug firing systems. One such system causes an ignition plug to emit a spark of long duration when an air/fuel charge is present in the combustion chamber, thereby ensuring good combustion. The other system causes the ignition plug to emit a spark of short duration and of very high energy when little, or no, charge is present in the combustion chamber, thereby aiding in the self-cleaning of the electrodes of the ignition plug.

Ignition system for a two cycle engine

An information communication apparatus includes acoustic and non-acoustic couplers, a switch for selectively connecting an information sending source of the apparatus to the acoustic or non-acoustic couplers, a setting unit for selectively setting items of a communication characteristic of each of the acoustic and non-acoustic couplers, a memorizing circuit for memorizing communication characteristics each having items the values of which are preset by the setting unit, a connection detector for detecting the connection of the acoustic coupler to a communication line, and an information sending controller. The controller connects the sending source to the acoustic or non-acoustic coupler by the switch in response to the acoustic coupler connection or not connection and controls the information sending according to the acoustic coupler or non-acoustic coupler communication characteristic from the memorizing circuit.

Facsimile apparatus adapted to communicate via an acoustic coupler

An improved method of operating a two cycle direct injected internal combustion engine so as to provide good ignition and combustion even when operating in a stratified condition. This is achieved either by extending the duration of firing of the spark plug either by extending a single firing or providing multiple firings per cycle or by changing the energy level across the gap of the spark plug during its firing.

Ignition system for two cycle engine

A fuel injection system for an internal combustion engine including a fuel injector that has an electric solenoid for its actuation that is powered by a battery. In the even the battery condition becomes depleted, the actuating pulse for the solenoid is advanced and extended in duration to accommodate the weakened state of the battery and maintain stable amount of fuel injection regardless of battery condition.

Electrically operated fuel injector

A fuel injection system including an arrangement for opening the injector valve after the engine has stopped so as to purge the injector of any accumulated fuel. The injection valve may be opened and closed through a number of repeated cycles which assist in the removal of carbon deposits or may be held open for a fixed time period. In addition, if the injector is of the air/fuel type, any compressed air in the chamber can be utilized to purge the fuel and also the opening of the injection valve will preclude the accumulation of air pressure in the system after the engine has been shut down.

Fuel injection control system

Several embodiments of induction systems for internal combustion engines that achieve high power outputs without sacrificing low and medium speed running characteristics or without adverse transitional effects. Each embodiment employs a pair of intake valves connecting with each combustion chamber and served by separate intake passages. A control valve is positioned at one of the intake passages and is operated so that the idle and low load requirements are primarily served by the other intake passage. An interconnecting passage interconnects the two intake passages downstream of the control valve and close to the engine valves to improve transitional performance and mid-range torque. In one embodiment of the invention the control valve is operated in response to engine speed and load as sensed in the induction system. In another embodiment an unbalanced control valve is employed that is operated by pressure differences in the induction system. In yet another embodiment the control valve is operated in response to the exhaust gas pressure. In still another embodiment a piston type control valve is employed.

Growing community of inventors

Iwata, Japan

Akira Yamada