Some Measurements of the Piston Temperatures in a Small Type Gasoline Engine

Abstract

The piston temperatures of two 4-stroke agricultural engines and a 2-stroke motor cycle engine were measured accurately by means of the thermocouple method, in which the thermocouple-wires were connected with the moving piston and a fixed point without any joint on the way. For this purpose we used the following two devices : (i) The thermocouple-wires were put on a spring which was fixed to the piston skirt at one end and to the crank case wall at the other end. (ii) A conduit containing the thermocouple-wires was movable with the piston through the combustion chamber. With the former device, the measurement was carried out at the speed up to 4000 rpm for a 4-stroke engine of stroke 65 mm, and with the latter, at the speed up to 8000 rpm for a 2-stroke engine of 40 mm stroke.