Patent · US Active

Speed reduction method for hand-carried engine-driven working machine

US9188066B2 · kind B2 · utility

2Cited by
10References
2Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJan 18, 2013
Grant dateNov 17, 2015
Priority date
Expiry dateFeb 20, 2034

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/40
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A speed reduction method for a hand-carried engine-driven working machine is provided in which a speed reduction of an engine can be attained reliably and safely by preventing the occurrence of lean come-down phenomenon in such a state that the engine is operating in a practical revolution speed range. An acceleration is calculated based on a change in revolution speed, and when the acceleration becomes smaller than a predetermined threshold, an ignition timing is retarded by a desired amount based on a determination that the engine is being decelerated, and further, a fuel flow rate is also increased, whereby the decelerated state of the engine is maintained without fail, so that the occurrence of lean come-down phenomenon is prevented in the process of reducing the revolution speed of the engine.

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