Patent · US Expired

Engine including a piston member having a high top ring groove

US4941440A · kind A · utility

17Cited by
19References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 7, 1989
Grant dateJul 17, 1990
Priority date
Expiry dateAug 7, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/12
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

Present day diesel engines having aluminum piston assemblies are limited to combustion chamber pressures of approximately 12,410 kPa (1,800 psi) whereas the desire is to increase such pressures up to the 15,170 kPa (2,200 psi) range. To reach such levels the instant engine has a piston assembly including a steel piston member having an upper cylindrical portion of a diameter D and defining a top surface, a depending tubular wall having a top ring groove a minimal elevational distance TRH below the top surface, and an annular cooling recess located beneath the top surface and juxtaposed to the top ring groove for removing heat away therefrom in use. The piston member is preferably forged and subsequently machined to precisely controllable dimensions, and has a ratio of TRH to D of less than 0.06. Moreover, the piston assembly is preferably of the articulated type and includes a forged aluminum piston skirt connected to the piston member through a common wrist pin. The skirt has an upwardly facing oil trough that is disposed in a cooperating relationship with the cooling recess of the piston member. A midsupported cylinder liner surrounds the piston assembly and a recess is provided …

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