VARIABLE COMPRESSION RATIO PISTON MACHINE AND METHOD FOR ADJUSTING THE VARIABLE COMPRESSION RATIO PISTON MACHINE

摘要

The present invention relates, in particular, to a variable compression ratio (VCR) piston machine comprising a crankshaft, at least one connecting rod, which is rotatably mounted on the crankshaft, wherein the connecting rod has a small bearing eye and a large bearing eye, and wherein the connecting rod has a connecting rod shaft, further comprising a compression piston, which is arranged on the connecting rod, preferably a combustion chamber piston which can be adjusted by means, for example, of an eccentric or some other adjusting element and of an adjustment system, preferably an adjustment linkage, wherein the adjustment system is supported by means of at least one support piston, which can be moved in a support cylinder of the connecting rod. A proposal is furthermore made for a method in which an adjustment accomplished by external forces acting on the adjustment system is supplemented or improved by additional adjustment forces.

主权项

1. A reciprocating-piston machine having a reciprocating-piston internal combustion engine which may be operated with a variable compression ratio and may be operated in various operating modes such as part load and full load, comprising:
a housing; a rotatably mounted crankshaft arranged in the housing; at least one connecting rod having a first end and a second end, the first end having a rotary bearing for the rotatable mounting of the connecting rod on the crankshaft; a compression piston rotatably mounted on the second end of the connecting rod, the second end is opposite the first end of the connecting rod and can be adjusted relative to the connecting rod; an adjustment mechanism for adjusting the compression piston relative to the second end of the connecting rod for the purpose of changing the compression ratio; the adjustment mechanism has an adjusting element coupled to the compression piston, and at least one support- and adjustment influencing unit for selectively supporting or locking the adjusting element, said unit having at least one support cylinder arranged in and/or on the connecting rod, and a support piston movable in said cylinder, having a piston rod in operative connection with the adjusting element; a first adjustment position of the adjusting element corresponds to a first compression ratio and at least one second adjustment position of the adjusting element corresponds to a second compression ratio higher than the first compression ratio; and an oil lubrication system for supplying the rotary bearing and/or at least one rotary bearing of the connecting rod with oil; the oil lubrication system has an oil pump and a control unit, the control unit controls the oil pump for the purpose of producing an oil pressure variable in accordance with the operating mode; the oil lubrication system is in fluid connection with the support cylinder of the support- and adjustment influencing unit; the control unit activates the oil pump of the oil lubrication system in order to provide oil to be fed to the support cylinder at a pressure that is modified relative to the oil pressure currently required to supply the rotary bearing and/or the rotary bearings of the connecting rod, more specifically for the purpose of assisting the adjustment of the adjusting element out of the first adjustment position in the direction of and/or into the second adjustment position and/or for the purpose of damping or throttling the adjustment and/or the speed of adjustment of the adjusting element out of the second adjustment position in the direction of and/or into the first adjustment position.