To always stably fix a cylinder in spite of size of cylinder.
A cylinder frame 1 is constituted by forming 5 a cylinder holder 2 and a back rest part 4 from metallic framing and, in band holding holes 12 at three positions formed on fore frames 7 and 7, a mount band 13 is attached while turning behind the respective fore frames 7 and 7. Besides, at the attaching sections of mounting band 13 with the fore frames 7 and 7, leaf springs 15 constituted by forming metallic bands in the shape of C are respectively provided inside, and the sections internally provided with the leaf springs 15 on the mounting band 13 are elastically kept bent by the leaf springs 15. Thus, the cylinder placed at the cylinder holder 2 can be surely fixed while utilizing the mounting band 13.