An engine piston having a piston upper part, a piston lower part connected to the piston upper part, a piston pin mounted in the piston lower part connects the piston to a connecting rod, and a first cooling space between the piston upper and lower parts for cooling oil. The first cooling space is connected to a second cooling space formed between the piston upper part and a piston lower part via at least one transfer bore, a cooling oil conduction sleeve for conducting cooling oil through a bore in the connecting rod towards the first cooling space. A guiding surface of the cooling oil conduction sleeve adjoins a support face of the piston lower part. At least one groove circulating in the circumferential direction is introduced into the guiding surface of the cooling oil conduction sleeve and/or into the support face of the piston lower part.

A small end of a connecting rod includes an oil supply hole extending from an outer surface to an inner surface of the small end. The oil supply hole includes an oil storage groove and a communication hole. The oil storage groove is recessed from the outer surface and extends along the circumference of the small end. The communication hole extends through a bottom surface of the oil storage groove and connects the outer and inner surfaces. Opposite edges of the oil storage groove contact the outer surface in a direction the oil storage groove extends. The bottom surface of the oil storage groove has an opening contacting a wall surface of the communication hole. When the small end includes a distal end of the connecting rod defining a top, the opposite edges are located between the top and the opening in the bottom surface of the oil storage groove.

A piston construction with an end surface is equipped with a pattern of insulating cavities embedded in an upper end of the piston, between the end surface and interior portions of the piston that are cooled by circulating liquid coolant.

The invention relates to a longitudinally adjustable connecting rod (7) for a reciprocating piston engine, in particular a reciprocating piston internal combustion engine, a reciprocating piston engine, and a vehicle comprising a reciprocating piston engine. The longitudinally adjustable connecting rod (7) comprises a longitudinal adjusting mechanism (8) for adjusting an effective length (L) of the connecting rod, a hydraulically actuated control device (12), switchable at least between two control modes, for controlling the longitudinal adjustment, and an electromagnetically actuated hydraulic switching valve (9) for hydraulically actuating the control device (12).

A device lubricates a connecting rod bearing on a crankshaft of an internal combustion engine. The device has a piston having an internal piston cooling fluid channel, and an outlet channel in fluid communication with the fluid channel. The device has a connecting rod, which is connected to the piston in an articulated, in particular pivotable, manner, and has a large connecting rod eye and a connecting channel. The large connecting rod eye is formed for receiving the connecting rod bearing. The connecting channel forms a fluid connection between the outlet channel and the large connecting rod eye so that a fluid, in particular a cooling lubricating fluid (e.g. oil), can be fed, or is fed, from the fluid channel to the large connecting rod eye via the outlet channel and the connecting channel. The connecting rod bearing can be lubricated by cooling oil from the fluid channel of the piston.

A telescopic control connecting rod for a variable compression ratio engine, comprises: a small end having, respectively, an eye and a piston at its ends; a big end serving as cylinder body in which the piston defines a first and a second hydraulic chamber, and a third side chamber located between the first and the second hydraulic chambers; the big end comprises two coaxial side bearings configured to establish a pivot link with a fixed part of the engine; a lubrication circuit comprising at least a first duct provided in the big end, connecting an inner space of each side bearing and the third chamber, whatever the length of the connecting rod, and comprising at least one second duct provided in the small end, connecting the third chamber and the eye.

A link component (150) with an oil hole (150E) is attached to a crankshaft (106) of an internal combustion engine (E), and the oil hole (150E) allows communication from an outside to the crankshaft (106) side. The oil hole (150E) has an inclined surface (150F) along an opening rim on the crankshaft (106) side. A surface other than the oil hole (150E) has a carbon concentration of 0.5 wt % or more. The inclined surface (150F) has a carbon concentration within a range of 0.7 wt % or more and 0.9 wt % or less. Production cost is suppressed, and at the same time, damage is prevented by increasing resistance of the oil-hole part on which stress is liable to concentrate.

A linear reciprocating piston engine including a cylinder; a piston located within the cylinder, the piston separating upper and lower combustion chambers of the cylinder; a separation plate disposed across a lower end of the cylinder to seal the lower combustion chamber; and a joint disposed in the separation plate. The joint includes a bore through which a connecting rod extends to connect the piston to a crankshaft. Movement of the piston along a longitudinal axis of the cylinder causes the connecting rod to rotate the crankshaft, said rotation of the crankshaft causing both transverse and angular movement of the connecting rod relative to the longitudinal axis of the cylinder. The angular movement of the connecting rod causes a corresponding angular movement of the joint. The joint includes a curved outer surface and an inner seal disposed between the bore and the connecting rod.

Provided is a compression ratio varying mechanism, including a communication hole including: a first opening opened in an outer peripheral side surface of a piston rod; and a second opening, which is prevented from being opposed to the first opening in a radial direction of a piston rod, and is connected to an oil passage at a position apart from the first opening in a stroke direction.

The invention relates to a length-adjustable connecting rod for a reciprocating piston engine, particularly a reciprocating piston internal combustion engine, comprising a hydraulic arrangement with which a length of the connecting rod can be adjusted, and a switching valve for controlling the inflow and outflow of a hydraulic medium into or out of the hydraulic arrangement, wherein the switching valve can be actuated electromagnetically.