Patent ID: 8534196

Claim:
A transportation system comprising: a transportation unit configured to move along a designated path and selectively connectable to a pull cable by a coupling device; and an auxiliary drive device extending along the designated path and configured to move the transportation unit along a portion of said designated path, said auxiliary drive device including a synchronous linear electric motor having: a linear stator extending along said portion of said designated path, said linear stator including a succession of one of: a plurality of electric coils and a plurality of permanent magnets, and a slide associated with said transportation unit, said slide configured to be magnetically connected to the linear stator when the transportation unit moves along said portion of said designated path, said slide including another one of: the plurality of permanent magnets and the plurality of electric coils and said slide including two sets of permanent magnets, each set of permanent magnets facing the other set of permanent magnets, and both sets of permanent magnets being configured to face the linear stator along said portion of said designated path.