A coupling/uncoupling mechanism (10A, 10B, 10C), employed for coupling and uncoupling two couple-able sections (11a, 11b, 12, 131) to and from each other, comprising a bar-shaped male coupling body (30A, 30C) and a female coupling body (20A, 20B, 20C), having an insertion space for inserting and withdrawing the male coupling body (30A, 30C), wherein said male coupling body (30A, 30C) has an engageable surface, which intersects a lengthwise direction thereof and faces a withdrawing direction, wherein said female coupling body (20A, 20B, 20C) comprises: a support member having a shape for supporting a state in which said male coupling body (30A, 30C) is inserted in said insertion space; a lever member, provided in a position facing said insertion space, and having one end and the other end, said one end being connected to said support member by a lever support-coupling section, said other end being configured to be movable in a direction toward a side opposing to said insertion space by the lever support-coupling section; wherein said support member includes a support front section, which constitutes a front section of said female coupling body (20A, 20B, 20C) and has an opening for inserting and withdrawing said male coupling body (30A, 30C) in and from said insertion space, and a support side section, which constitutes a section facing said lever member, characterized in that the coupling/uncoupling mechanism (10A, 10B, 10C) comprises an engaging member, rotatably connected at one end thereof to a position between both ends of said lever member via a lever rotation-coupling section, and having an engaging surface, which is contacted with said engageable surface of said male coupling body (30A, 30C) from the withdrawing direction; and a link member, rotatably connected at one end thereof to the other end of said engaging member via a link rotation-coupling section positioned away from said lever rotation-coupling section and in proximity to said engaging surface, in an inserting direction, and rotatably connected at the other end thereof to said support member via a link support-coupling section, wherein, when said male coupling body (30A, 30C) is coupled to said female coupling body (20A, 20B, 20C), said male coupling body (30A, 30C) is inserted in the insertion space, the other end of said lever member is disposed in a position in proximity to said insertion space, and a condition in which said engaging surface of said engaging member is contacted with said engageable surface of said male coupling body (30A, 30C) is maintained, and wherein, when said male coupling body (30A, 30C) and said female coupling body (20A, 20B, 20C) are uncoupled, the other end of said lever member moves along a direction of being apart from said insertion space so that said engaging surface of said engaging member moves toward a withdrawing direction, resulting in releasing the contacting between said engaging surface and said engageable surface of said male coupling body (30A, 30C). a support member having a shape for supporting a state in which said male coupling body (30A, 30C) is inserted in said insertion space; a lever member, provided in a position facing said insertion space, and having one end and the other end, said one end being connected to said support member by a lever support-coupling section, said other end being configured to be movable in a direction toward a side opposing to said insertion space by the lever support-coupling section; wherein said support member includes a support front section, which constitutes a front section of said female coupling body (20A, 20B, 20C) and has an opening for inserting and withdrawing said male coupling body (30A, 30C) in and from said insertion space, and a support side section, which constitutes a section facing said lever member, characterized in that the coupling/uncoupling mechanism (10A, 10B, 10C) comprises an engaging member, rotatably connected at one end thereof to a position between both ends of said lever member via a lever rotation-coupling section, and having an engaging surface, which is contacted with said engageable surface of said male coupling body (30A, 30C) from the withdrawing direction; and a link member, rotatably connected at one end thereof to the other end of said engaging member via a link rotation-coupling section positioned away from said lever rotation-coupling section and in proximity to said engaging surface, in an inserting direction, and rotatably connected at the other end thereof to said support member via a link support-coupling section,