The main purpose of this experiment was to find out the vibration level of one-man gasoline chain saw widly using for forest operations in this country.
Measuring equipments used for the test were a dynamic strain amplifier, a electro-magnetic oscillograph and three accelometers utlizing the principle of wire resistance strain gage & so on. (Fig. 1)
The results of these tests are considered as follows :
1. Ten chain saws were examined at the highest running speed of saw chain and vibrate acceleration ( g≒9800 mGal ), frequeny ( c/s ) and amplitude (mm) were determined These results are shown in Table 1.
2. Relations between the tensity of saw chain and the vibration level in their running were tested with two chain saws. From the results, it is not too much to say that the tensity of saw chain has nothing to do with the level (G). (Table 2)
3 . The variations of level (G) in cutting log are nearly proportional to the revolution of engine (rpm) . (Fig. 3)
4. Relation between the level (G) and the running speed of saw chain is expressed by the following formular
G = αV - β
where α, β are constants depending upon the various kinds of chain saw. (Fig.4, Fig.5)