摘要 |
First and second masts of a stacker crane are provided in a travelling vehicle main body to be spaced away from each other in an X-direction and extending in a Z-direction. First and second travel wheels are mounted to the travelling vehicle main body to be spaced away from each other in the X-direction, and roll on an upper surface of a lower guide rail. First and second drive wheel units are provided in the travelling vehicle main body to be spaced away from each other in the X direction. Each of the first and second drive wheel units includes a first drive wheel and a second drive wheel. The first drive wheel is in contact with a first side surface of the lower guide rail, and the second drive wheel is pivotably attached to the travelling vehicle main body and urged toward the first drive wheel so that the second drive wheel is in contact with a second surface of the lower guide rail. |