Exchangeable tool assembly for an endoscopic treatment device and such treatment device

An exchangeable tool assembly for an endoscopic treatment device, comprising:

• a rotating tool adapted to contact and treat a surface;
• a coupling element for coupling said tool assembly to a motor of a treatment device;
• a flexible shaft having a distal end and a proximal end, said distal end being connected to said rotating tool and said proximal end being connected to said coupling element, said flexible shaft transmitting a rotary movement of said motor to said rotating tool, said flexible shaft being connected to said rotating tool such that said flexible shaft and said rotating tool form a jointly exchangeable unit;
• and
• a locking mechanism for releasably holding said tool assembly at said treatment device, said locking mechanism comprising a locking element arranged at said rotating tool and a locking member arranged at said treatment device, which is engageable with said locking element to releasably hold said jointly exchangeable unit formed by said rotating tool and said flexible shaft, which can be withdrawn as a whole when the locking member arranged at said treatment device is disengaged from the locking element arranged at said rotating tool, and a locking sleeve, at least part of which is slideable along said treatment device, such that, when said sleeve is in a first position, said sleeve urges said locking member into engagement with said locking element and, when said sleeve is in a second position, said locking member is disengaged from said locking element.