BARNCHING AND JOINING SYSTEM OF OVER HOIST TRANSFER(OR OVERHEAD SHUTTLE) AND CONTROL METHOD THEREOF

PURPOSE: A sending-back system and a control method thereof are provided to prevent carrier collision by actively engaging in a signal changing process taking place when carriers branch out or a number of carriers get together reflecting a stoppage and the moving direction of the carriers. CONSTITUTION: A carrier unit includes a carrier (110) that returns a target object. An orbit unit includes a first orbit (121) and a second orbit (122) as well as a link orbit (123) that is required to organize a straight-up/curve section, a branching section, and a joining section. Multiple orbit sensors (131-140) are arranged in the first and second orbits as well as in the link orbit. The orbit sensor unit detects a carrier's entry into and escape from the branching and joining sections as well as the moving direction of the carrier while stopping the carrier when needed. A carrier sensor unit (150) transmits and receives a signal indicating the moving directions of the orbit sensor unit and the carrier as well as a signal able to stop the carrier. [Reference numerals] (AA) Joining section; (BB) Branching section; (CC) Branching/joining CON'T