The purpose of the present invention is to attach and drive a treatment tool while a constant initial tension is being applied to all of a plurality of tension transmission members of the treatment tool. Accordingly, this treatment-tool driving device (1), which is detachably attached to a treatment tool (3) provided with at least one pair of tension transmission members (2), and which uses the tension applied to the tension transmission members (2) to drive the treatment tool (3), is provided with: movable members (7) which are respectively detachably attached to one end of each of the tension transmission members (2) a driving source which generates motive power for driving the treatment tool (3) a motive-power transmission mechanism (9) which switches between coupling the driving source and the movable members (7), and releasing the coupling therebetween, and which, in the coupled state, transmits the motive power from the driving source such that tension is alternately applied to the two movable members (7) attached to the pair of tension transmission members (2) and an impelling means (10) which, while in the state in which the coupling by the motive-power transmission mechanism (9) is released, impels the two movable members (7) in the direction in which the tension is applied to the tension transmission members (2).La présente invention vise à fixer et à entraîner un outil de traitement alors quune tension initiale constante est appliquée à la totalité dune pluralité déléments de transmission de tension de loutil de traitement. En conséquence, ce dispositif dentraînement doutil de traitement (1), qui est fixé de manière détachable à un outil de traitement (3) pourvu dau moins une paire déléments de transmission de tension (2), et qui utilise la tension appliquée aux éléments de transmission de tension (2) pour entraîner loutil de traitement (3), est pourvu : déléments mobiles (7) qui sont respectivement fixés de manière amovible à une extrémité de chacun des
