<；P>；PROBLEM TO BE SOLVED: To enable change of a gas cylinder without opening/closing a cover body although a gas cylinder retaining part and an upper side of a muffler are covered by the cover body, and to enhance change work efficiency of the gas cylinder. <；P>；SOLUTION: The walking type control machine 1 is provided with: a gas engine 6 operated making a gas fed from the gas cylinder 8 as a fuel； the gas cylinder retaining part 12 for detachably retaining the gas cylinder 8； and the muffler 23 for attenuating the exhaust sound of the gas engine 6. The gas cylinder retaining part 12 and the muffler 23 are arranged on an upper part of a machine body of the walking type control machine 1. When the upper side of the gas cylinder retaining part 12 and the muffler 23 is covered by the cover body 30, the gas cylinder 8 is constituted so as to be attached/detached from one side part of the gas cylinder retaining part 12, and is arranged such that the one side part of the gas cylinder retaining part 12 is projected to the outside of the cover body 30. <；P>；COPYRIGHT: (C)2010,JPO&INPIT
