Kawasaki Jukogyo Kabushiki Kaisha

Takashi Mitadera

Shinichi Tamba

Tetsuaki Shirai

Yoshiro Yamane

Keiichi Nakamizo

Masato Sato

Kozo Watanabe

Naotake Nii

Tomozo Nakagawa

Fumikazu Miyanaga

There is disclosed a four-cycle engine in which a crankshaft and a cam shaft are disposed generally parallel to each other, and an intake port and an exhaust port are formed in a cylinder head. The intake port and the exhaust port are arranged in such a manner that a line passing through the centers of the intake port and the exhaust port is non-parallel to the axis of the crankshaft. With this arrangement, an intake passage and an exhaust passage can be greatly shortened, and therefore intake efficiency as well as exhaust efficiency can be enhanced, thereby enhancing the performance of the engine. In an air-cooled engine, the overheating of the engine is greatly restrained.

Four-cycle engine

A cam shaft for engine is constructed such that the cam shaft driven by a crankshaft is rotatably supported at both ends by respective journal bearing boxes. Either one of the journal bearing boxes is fed with pressure oil from an oil pump to cause the oil pressure gathered within the journal bearing box to act upon the end face of the cam shaft so that the cam shaft is normally biased in a constant axial direction.

Structure of cam shaft for engine

A lubricating system for an internal combustion engine is disclosed. This system includes a pair of passages formed between a crank chamber for reserving oil and an air-oil separating chamber accommodating a mechanism for actuating overhead valves. The pair of passages are constituted by a breather passage formed in the upper portion of a cylinder and the oil-returning passage formed in the lower portion of the cylinder. The breather passage has a valve for allowing a fluid to pass solely toward the air-oil separating chamber and a large oil-circulating resistance is imparted to the fluid flowing toward the air-oil separating chamber through the oil-returning passage, thereby circulating an oil mist in one direction only by using the reciprocal motion of each piston. Even when the engine is inclined, oil is prevented from flowing back from the crank chamber to the separating chamber through the oil-returning passage.

Lubricating system for horizontal cylinder overhead valve engine

The breathing device for the 4 stroke engine includes a first separating chamber formed as a tappet chamber and a second separating chamber provided above a crank case. The second separating chamber is arranged above the first separating chamber. The crank chamber and the first separating chamber are communicated to each other by a first oil return port and a first vent arranged above the first oil return port. The first separating chamber and the second separating chamber are communicated to each other by a check valve. The second separating chamber and the crank case are communicated to each other by a second oil return port.

Breathing device for four stroke engine

This disclosure relates to a combined breather-lubricator system for an internal combustion engine having a horizontal cylinder, a crankcase, a vertical crankshaft journalled by an upper and a lower bearings in the crankcase, and a valve spring chamber in the crankcase. The system includes two breather passages. The first breather passage extends from the crankcase through a check valve and the spring chamber and opening into the atmosphere, the valve being adapted to pass fluid therethrough in the direction from the crankcase to the atmosphere. The second breather passage extends back from the atmosphere through an oil drain hole in the spring chamber into the crankcase. The system further includes a lubrication system connected to the first breather passage.

Growing community of inventors

Akashi, Japan

Takashi Mitadera