Patent · US Active

Variable compression ratio internal combustion engine

US7721688B2 · kind B2 · utility

4Cited by
5References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 6, 2007
Grant dateMay 25, 2010
Priority date
Expiry dateJan 5, 2028

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02B75/041
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An internal combustion engine includes a variable compression ratio mechanism made up of a case-side bearing-forming portion, a block-side bearing-forming portion, and a shaft-shaped drive portion. The case-side bearing-forming portion is formed in an upper portion of a crankcase. The block-side bearing-forming portion extends outward from a lower end portion of an outer wall surface of the cylinder block. The block-side bearing-forming portion is linked to the case-side bearing-forming portion by the shaft-shaped drive portion. Slit-shaped stress reduction groove portions each having an opening in a region between the block-side bearing-forming portion and cylinder bores are formed in a lower surface of the cylinder block. Therefore, even when the block-side bearing-forming portion presses the outer wall surface, the stress reduction groove portions reduce the stress, so that the deformation of the wall surface of each cylinder bore can be restrained.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.