Yamaha Hatsudoki Kabushiki Kaisha

Hidenori Suhara

Tatsuyuki Masuda

Michihisa Nakamura

Kousei Maebashi

Jun Taue

Makoto Kosugi

Takeo Yoshida

Hidetoshi Ishigami

Hideaki Ito

Kohsei Maebashi

An exhaust control valve arrangement for a two cycle internal combustion engine for altering the compression ratio to provide optimum running under all conditions. An arrangement is provided or cleaning the exhaust control valve and its surrounding cooperating surfaces of the engine upon shutting off of the engine to preclude the formations of deposits that can cause sticking of the valve element. The valve element is rotated through a number of cycles after the engine is stopped through a wider range than during its normal valving operation for removing deposits. The number of cycles is chosen in response to an engine condition such as length of time of running or amount of lubricant supplied to the engine. Various valve arrangements are disclosed that improve the cleaning operation and permit cleaning even while the engine is running.

Exhaust control valve for engine

Embodiments of lubricating systems and methods for two cycle, crankcase compression, diesel engines wherein certain running components of the engine such as the crankshaft and pistons are each supplied with their own lubricating systems including independently operating lubricating pumps, each system is controlled so as to supply a finite amount of lubricant to the engine and then sense the engine running conditions to determine when the lubricant will have been consumed before additional lubricant is supplied. In addition, a control routine and structure is disclosed wherein lubrication is supplied to the engine before starting is initiated and wherein the amount of lubrication supplied is varied during break-in.

Lubricant control

An exhaust control valve arrangement for a two cycle internal combustion engine for altering the compression ratio to provide optimum running under all conditions. An arrangement is provided for cleaning the exhaust control valve and its surrounding cooperating surfaces of the engine upon shutting off of the engine to preclude the formations of deposits that can cause sticking of the valve element. The valve element is rotated through a number of cycles after the engine is stopped through a wider range than during its normal valving operation for removing deposits. The number of cycles is chosen in response to an engine condition such as length of time of running or amount of lubricant supplied to the engine. Various valve arrangements are disclosed that improve the cleaning operation and permit cleaning even while the engine is running.

A four cylinder, two cycle crankcase compression, diesel fuel injected engine having an improved injection pump including an integral timer for timing the initiation and duration of fuel injection. A control system and method is disclosed for maintaining uniform running speed during all running conditions while reducing the amount of smoke produced by the engine. The speed uniformity is obtained by selecting a cylinder that deviates from the desired speed and adjusting the fuel injection of the cylinder firing preceding that cylinder on the next cycle. The engine also includes an improved arrangement for determining the timing of an event by measuring the incremental rotational speed of the engine immediately prior to the event to be timed.

Fuel injection unit for engine

A high pressure fuel injection control system for maintaining idle speed of an injected high speed diesel engine. Idle speed is maintained by holding either pressure supplied to the injector constant and varying the duration of timing or holding the duration of timing constant and varying the pressure depending upon the desired running condition to achieve the desired engine performance.

Idling control device for high pressure fuel injection engine

A fuel injection system and method for a fuel injected engine of the multi cylinder type for minimizing variations in crankshaft speed due to variations in individual cylinder to cylinder firing. These variations are compensated for by changing the fuel injection and specifically the duration of the fuel injection. The engine speed is measured for each cylinder either by the time required to reach top dead center from a predetermined angle, the time to reach bottom dead center from a predetermined angle, or from the average speed.

Growing community of inventors

Iwata, Japan

Hidenori Suhara