Analysis of working processes and efficiency assessment of hand-held power tools

Small displacement, single cylinder engines with spark ignition are used as a low cost propulsion in many applications like scooters, motor cycles, small boats and handheld power tools. These engines follow two- or four-stroke principle and are usually realized with a carburetor. They represent an affordable and simple as well as durable propulsion technology, but concurrently their efficiency is low and emissions are high. Consequently, the share of these small engine applications of total emissions and fuel consumption is not negligible. Therefore, the demand to increase efficiency of these engines is rising and the development of suitable and cost efficient methods is required.