US Patent 7780055 Loading unit having drive assembly locking mechanism

A disposable loading unit is provided which includes a tool assembly and a body portion. A drive assembly is movably positioned at least partly within the body portion and is operably associated with the tool assembly to operate the tool assembly. A locking mechanism is provided for maintaining the drive assembly in a prefired position prior to and during attachment of a DLU to a surgical instrument. The locking mechanism includes a locking member and a locking member actuator. The locking member actuator is movable to move the locking member to an unlocked position in response to linear insertion of an insertion tip of the DLU into a surgical instrument.