US Patent 7774985 Drive apparatus for sliding member

A driving apparatus for a sliding member includes a housing, a cable, a drum to move the cable to open and close the sliding member, a motor arranged to drive the drum, and a tensioner supported by the housing arranged to provide a tensioning force to the cable, the tensioner is arranged: to be switched from a first state where an urging force of a spring is stored to a second state where the urging force of the spring is released, to be moved from a first position where the tensioner does not provide the tensioning force to the cable to a second position where the tensioner provides an initial tensioning force to the cable when the tensioner is in the first state, and to be fixed in the second position and to be switched to the second state to provide the tensioning force to the cable by the urging force of the spring.