A multi-link piston crank mechanism includes a crank pin bearing portion including a crank pin bearing central portion that is disposed at a center thereof in an axial direction of a crank shaft. The crank pin bearing central portion at a portion positioned on the first end side of the lower link is thicker in a radial direction of the crank pin than a portion positioned on the second end side of the lower link. The second control link end portion is thicker along a radial direction of the second through hole than the second upper link end portion along a radial direction of the first through hole.

The invention relates to a diesel engine with high-pressure injection and supercharging (Question to inventor: which components define a diesel engine with the corresponding properties and/or a compression temperature of more than 700 C. and/or a combustion temperature of more than 1200 C., a cylinder or several cylinders with a respective cylinder bore, a connecting rod associated with a respective cylinder and a piston arranged in the respective cylinder bore with a top side, an under side and a circumferential surface with a temperature of more than 700 C. and/or a combustion temperature of more than 1200 C., an under side and a circumferential surface with a nominal diameter, the upper side being designed to absorb pressure forces of a gas inside the respective cylinder, the underside having a connecting rod holder with an undercut acting in a tensile and a pressure direction, so that the connecting rod holder is designed to positively receive a head region of the respective connecting rod which corresponds to the receptacle and is pivotable about a pivot axis, and the circumferential surface is designed to guide the piston in the respective cylinder bore along an axis of movement and with a ring groove for a piston ring for sealing the piston with respect to the respective cylinder bore and has a circumferential collar extending from the upper side with a height arranged between the upper side and the ring groove for the piston ring. Furthermore, the invention relates to a corresponding piston of a diesel engine.

An opening on one end side of a pin-boss oil passage opens to the inner circumferential surface of a pin boss part of an upper link, while an opening on the other end side thereof opens to the outer circumferential surface of the pin boss part of the upper link. A lower-link oil passage has a one-end-side opening structured to open to a pin-boss-facing surface of the lower link facing the outer circumferential surface of the pin boss part of the upper link and its other-end-side opening structured to open to a crankpin bearing surface. The lower-link oil passage is configured to point, at a prescribed crankangle, to a specified end edge of end edges of the other-end-side opening of the pin-boss oil passage, the specified end edge facing one end side of the upper link.

The present invention refers to a crankshaft (1) for an alternative compressor comprising a main shaft (21) connected to an eccentric pin (2) by means of a peripheral flange (3) containing a lubricating hole (24) extending through said eccentric pin (2) and through at least part of the body of main shaft (21), one of the edges of said hole (24) being on the cylindrical surface (2a) of said eccentric pin (2). With this type of hole, the present invention allows for the use of shafts having extremely low diameters (and, as result, with low viscous loss), even with high eccentricities, whereby an excellent capacity of oil pumping and mechanical strength is maintained.

There is provided a bearing apparatus of a crankshaft for an internal combustion engine. The bearing apparatus includes a crankshaft having a plurality of journal portions and a plurality of crank pin portions; a main bearing supporting the crankshaft; and a bearing housing holding the main bearing. The plurality of journal portions include a first journal portion having a lubricating oil passage and a second journal portion not having the lubricating oil passage. The first and second journal portions and are supported by the first and second main bearings and. The bearing housing includes an Al alloy upper housing and an Fe alloy lower housing. The groove depth of the oil groove of the upper half bearing of the second main bearing is one half or less than the groove depth of the oil groove of the upper half bearing of the first main bearing.

An engine lubrication structure supplies oil from an oil pump to individual components of an engine in which a balancer shaft is disposed parallel with a crank shaft in a crank case, the engine includes a turbocharger which compresses intake air using exhaust gas of the engine; a main gallery which supplies oil to a bearing of the crank shaft and a bearing of the balancer shaft and a sub-gallery which supplies, to individual components of the engine, oil that has been supplied to the bearing of the balancer shaft are provided in the crank case; and an oil passage which supplies oil to the turbocharger is connected to the sub-gallery.

The oil filter device is disposed on a side portion of one side of a cylinder body in a width direction in a cylinder head side with respect to an engine case in a space between center lines of main lubricating oil passages and a cylinder axis line of the cylinder body, and includes an oil pump disposed on the engine case and further lubricating oil passages that connect to the main lubricating oil passage.

An engine case includes bearings, an oil pump, lubricating oil passages, and a relief device. The bearings rotatably support a crankshaft and a camshaft. The oil pump and the lubricating oil passages are configured to pressure-feed lubricating oil to the bearings. The relief device is configured to adjust a pressure of the lubricating oil. The lubricating oil passages include main lubricating oil passages. The main lubricating oil passages include communication portions linearly formed with extending portions. The communication portions communicate between the respective bearings of the crankshaft and the camshaft from outside the engine case. The extending portions extend from outside the engine case to the bearing of the camshaft. The relief device is disposed having a relief valve and a relief hole at the extending portions.

A system for lubricating a crankshaft of an engine includes a first main journal including a first shaft and in fluid communication with an oil supply. The system also includes a first main journal oil passage in fluid communication with the oil supply extending through the first shaft. The system also includes a first pin journal including a first crank, and a first oil passage extending partially through the first crank in fluid communication with the first main journal oil passage. The system also includes a second pin journal including a second crank, and a second oil passage extending partially through the second crank in fluid communication with the first main journal oil passage. Each of the first oil passage extends at a first non-zero angle and the second oil passage extends at a second non-zero angle relative to the first main journal oil passage.

A hollow cast iron crankshaft of an internal combustion engine includes at least one main bearing journal and at least two connecting rod bearing journals. The crankshaft is provided with a plurality of internal oil supply bores to lubricate the connecting rod bearing journals. An outer circumference of the main bearing journal is in fluid communication with an outer circumference of two connecting rod bearing journals by the supply bores.