Patent ID: 9650952
Date: 2017-05-16
CPC Classifications: F01M,F02B,F02D,F16C

Claim:
1. A variable compression ratio internal combustion engine comprising: a variable compression ratio mechanism configured to change an engine compression ratio depending on a rotational position of a control shaft arranged in an oil pan of an engine main body; an actuator configured to change and hold the rotational position of the control shaft: and a linking mechanism configured to link the actuator and the control shaft, the linking mechanism comprising: a lever linked to the control shaft; and a connecting pin rotatably linking a tip of an arm part extending radially outward from a center of the control shaft and one end of the lever, wherein at least when having been set to a highest compression ratio, the connecting pin is set such that the connecting pin is submerged below an oil level of the oil pan, for supplying lubricating oil to the connecting pin and for suppressing noise and vibrations at high compression ratios containing the highest compression ratio, and wherein: when having been set to a high compression ratio, the connecting pin is set to be always submerged below the oil levels of the oil pan regardless of respective positions of the oil levels of the oil pan during oil-level fluctuations.