PROBLEM TO BE SOLVED: To solve the problem: attachment requires much labor because alignment is difficult, when a bonnet is attached to a floor step from above.SOLUTION: A notched part, the front of which is opened, is formed on a floor step 26 parallel guide grooves 31 (guide parts) are formed on right and left sides along right and left edges 30a of the notched part 30, respectively and a bonnet 16 is attached in such a manner as to slide along the guide grooves 31 from the front of a traveling machine body 5. At least a rear part of the guide groove 31 comprises a groove 35 that is formed in a U-shape in a frontal view, and the bonnet 16 is fitted into the groove 35.COPYRIGHT: (C)2014,JPO&INPIT【課題】ボンネットをフロアステップに対して上方から取り付けると、位置合わせが困難で取付けに手間がかかっていた。【解決手段】フロアステップ26に前方が開放される切欠き部を形成すると共に、該切欠き部30の左右の縁30aに沿って左右に平行な案内溝31(案内部)を形成し、ボンネット16を走行機体5の前方から案内溝31に沿ってスライド移動させて取付ける。案内溝31の少なくとも後部分は正面視∪字状に形成される溝35からなり、該溝35にボンネット16が嵌合する。【選択図】図3