Patent · US Expired

Operator carried power tool having a four-cycle engine

US5241932A · kind A · utility

29Cited by
4References
26Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 2, 1991
Grant dateSep 7, 1993
Priority date
Expiry dateDec 2, 2011

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02B2275/34
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A hand held powered tool is provided which is intended to be carried by an operator during use. The power tool has a frame, including a handle to be grasped by the operator, an implement affixed to the frame having a rotary input member and a small four-cycle lightweight internal combustion engine attached to the frame for driving the implement. The four-cycle engine is made up of a lightweight aluminum engine block having a cylindrical bore and an enclosed oil reservoir formed therein. A crankshaft is journaled to the engine block for rotation about a crankshaft axis. A piston reciprocates within the bore and is connected to the crankshaft by a connecting rod having oil splasher formed thereon for intermittently engaging the oil within the enclosed oil reservoir to splash lubricate the engine. The engine is provided with a cylinder head assembly defining a compact combustion chamber having a pair of overhead intake exhaust ports cooperating intake and exhaust valves. A lightweight high powered engine is thereby provided having relatively low HC and CO emissions.

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