Patent ID: 9102077
Filing Date: 2015-08-11
Classification: B23D,B25F,B28D,F01N,F02B,F16F

Abstract:
1. A portable, hand held power cutter comprising: a tool unit having at least one working tool, which can be rotated about an axis of rotation, and preferably having a tool guard; a drive unit comprising a single cylinder internal combustion engine, the engine comprising a single engine cylinder with cylinder bore having a center line, a sidewall, and a top and an exhaust port formed in the sidewall of the engine cylinder, a crankshaft, a crankcase and an assembly for supplying air and fuel to the engine, wherein a piston is configured to close the exhaust port when the piston is adjacent and covering the exhaust port and to open the exhaust port when the piston is below the exhaust port; a cutter arm attached to the drive unit in its inner end and its outer end carrying the tool unit; and a muffler accommodated in a close and side by side relationship with the engine cylinder; the muffler comprises an exhaust gas inlet and an exhaust gas outlet, such that the exhaust gas inlet is adapted to receive the exhaust gases from the exhaust port of the engine cylinder; the exhaust gas inlet is provided on a substantially top or bottom or a local side of the muffler; the muffler is arranged to be in communication with the exhaust port of the engine cylinder by means of a pipe for improving an air flow around the pipe and around the exhaust port of the engine cylinder to thereby lower the temperature of the exhaust port of the engine cylinder and the exhaust gases entering the exhaust gas inlet of the muffler.