Studies on the Protective Frame for Agricultural Tractors

For Tractors in Hokkaido

Abstract

The amount of agricultural tractors in 1973 is about 350000 in all area of Japan and about 60000 in Hokkaido. The 75-80 percent of large tractor over 35PS in Japan are used in Hokkaido. Increasing of tractors, increased accidents by tractors and many operators died. In order to decrease death by overturn of tractors, the protective frames are tried to attach with tractors.
The 20 protective frames were tested according to the static tests of ASAE-SAE standars for farm tractor overturn protection. The design of the protective frame bigins to come into focus that it achieves a static test force-deflection relation that permits the protective frames to have both acceptable energy imparting and energy absorbing behavior. A casual consideration of this objective might lead to the conclusion that energy imparting and energy absorbing are contradictory repuirments because they require different force-deflection relations. The ideal design is to combine the virtues while avoiding the shortcomings of each.