<；P>；PROBLEM TO BE SOLVED: To provide a wheel downsized as a whole and adjustable according to a height of a step. <；P>；SOLUTION: The wheel to run on a step includes: a rotation support 7； turning claws 9 ； and a developing driver 11. The rotation support 7 has a plurality of claw supports 17, 19, 21 and 23 which are provided at a predetermined interval in a circumferential direction and protruded in a radial direction. The turning claws are rotatably supported by the front ends of the claw supports 17, 19, 21 and 23, respectively, form a turning circumferential surface P, cooperating with each other in the respective circumferential directions in closing rotation positions to the radial direction, and protrude outside the turning circumferential surface P in developing rotation positions to the radial direction with respect to the claw supports 17, 19, 21 and 23. The developing driver 11 adjusts and drives the developing rotation positions of the respective claws 9. <；P>；COPYRIGHT: (C)2011,JPO&INPIT
