Patent · US Expired

Chain saw

US4178685A · kind A · utility

14Cited by
4References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 21, 1978
Grant dateDec 18, 1979
Priority date
Expiry dateJul 21, 1998

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02B2075/1808
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A chain saw driven by a two-cycle opposed cylinder engine of simultaneous ignition type. The vibration energies generated in respective cylinders are offset by each other partly because the cylinders are made to oppose to each other, and partly because the ignitions of these cylinders take place simultaneously. Further, the opposed cylinder engine provides ample spaces above and below the cylinders. These spaces are conveniently used for accommodating intake system including a carburetor and so forth and exhaust system including a muffler and so forth. Sound shielding walls are disposed in the ample space around the cylinders so as to insulate the noise caused by the engine and, at the same time, to define a sufficiently large cooling air passage.

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