US Patent 10153189 Carrier buffering device and buffering method

Without a lateral transfer mechanism in a local vehicle, the buffering capacity of a temporary storage apparatus is increased. The temporary storage apparatus stores carriers temporarily between overhead travelling vehicles and load ports. A travelling rail for the local vehicle is provided to allow the local vehicle to run below the travelling rail for the overhead vehicles and over the load ports. A slidable buffer slidable between a position under the travelling rail for the local vehicle and a position shifted laterally and a controller for controlling the local vehicle and the slidable buffer are provided, and the local vehicle waits at a position separated from an area over the load ports.