| 摘要 |
A conventional endless belt is made of a comparatively flexible member such as rubber. When the endless belt comes in contact with a gap, part of the belt is pushed inward against the gap to be depressed and as a result, a greater power is needed for the endless belt to climb over the gap and it becomes easily jamed. According to the present invention, a caster of an endless structure is provided which is almost jam-proof even in the case of a bigger gap. The caster comprises a first wheel 3 supported on a mounting leg 2, a second wheel 4 supported by an axle 8 on one end of a suspension arm 7 of which the other end is supported by an axle 6 which also supports the first wheel 3, and a wrap-around member 5 which is wrapped around the first and second wheels 3 and 4. The wraparound member 5 is formed an endless belt form by connecting independent pieces 25 to each other. The outer peripheral section of each piece 25 is provided with a wider section and when the wraparound member is depressed and warps, the wider section is adapted to touch a wider section of the adjacent piece 25, thereby preventing further depression. |
