Patent · US Expired

Two-stroke internal combustion engine

US7574984B2 · kind B2 · utility

4Cited by
34References
44Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 23, 2005
Grant dateAug 18, 2009
Priority date
Expiry dateMay 23, 2025

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02B2075/025
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A crankcase scavenged two-stroke internal combustion engine (1) in which a piston ported air passage is arranged between an air inlet (2) and the upper part of a number of transfer ducts (3, 3′). The air inlet is equipped with a restriction valve (4), controlled by at least one engine parameter, for instance the carburetor throttle control. The air inlet extends via at least one connecting duct (6, 6′) to at least one connecting port (7, 7′) in the engine's cylinder wall (12). The connecting port (7, 7′) is arranged so that when the piston is in a top dead center configuration, it is connected with flow paths (9, 9′) embodied in the piston (13). The flow paths (9, 9′) extend to the upper part of a number of transfer ducts (3, 3′), and the flow paths in the piston are arranged so that the recess (10, 10′; 11, 11′) in the piston that meets the respective transfer duct's port (31, 31′) in a manner that the air supply is given an essentially equally long period, counted as crank angle or time, in relation to the fuel and air mixture inlet period.

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