Mazda Motor Corporation

Masashi Taniguchi

Takashi Sasada

Masakazu Tokuyama

Madoka Sakurai

Tetsuro Mutoh

Tokio Ishino

A skirt section of the cylinder block is shortened to the height of the rotational center of the crank shaft. To the bottom end of the skirt section is the lower cylinder block whose bottom end is coupled to the oil pan. The inner space of the lower cylinder block section is divided by plural partition walls extending transversely between the side walls of the lower cylinder block section. A bearing cap supporting the crank shaft has a boss section projecting transversely and a threaded hole is formed in the boss section. Further, the bottom end of the bearing cap has a threaded hole having an opening facing bottom. The lower cylinder block section is further provided at its side wall with a hole through which the side portion of the bearing cap is connected to the side wall of the lower cylinder block section. The bottom end of the bearing cap is connected to the side wall of the lower cylinder block section. This arrangement for the bearing caps improves rigidity for supporting the bearing caps, thereby permitting a decrease in the vibration of the engine.

Cylinder block structure for an internal combustion engine

A lubrication system for a multi-cylinder internal combustion engine has a valve drive mechanism equipped with a row of hydraulic valve lash adjusters installed in a cylinder head of an engine block of the engine and a camshaft with journals which is disposed over the cylinder head and is attached, at one end thereof, with a camshaft pulley coupled to a crankshaft pulley by a belt. The lubrication system includes a main oil gallery extending lengthwise in the engine body, a lash adjuster oil gallery formed in the cylinder head and extending along the row of hydraylic valve lash adjusters, and a camshaft oil gallery formed in the cylinder head and extending parallel to the lash adjuster oil gallery. The main oil gallery is connected independently to one end of the camshaft oil gallery adjacent the camshaft pulley and to one end of the lash adjuster oil gallery remote from the camshaft pulley so as to supply them with pressurized oil, fed by an oil pump, in opposite direction. The pressurized oil is carried, on one hand, to each camshaft journal through the camshaft oil gallery and, on the other hand, into a pressure chamber of each hydraylic valve lash adjuster through the lash adjuster oil gallery.

Growing community of inventors

Hiroshima, Japan

Masashi Taniguchi