Electromechanical surgical systems

A surgical loading unit selectively interconnectable with an adapter assembly including a rotatable drive shaft, the surgical loading unit comprising:

• an anvil jaw;
• and
• a cartridge jaw including:
• a mounting portion defining a receiving channel therein;
• a fastener firing assembly disposed within the mounting portion, the fastener firing assembly comprising a power screw and a gear member disposed at a proximal end of the power screw that is operably engagable with the rotatable drive shaft of the adapter assembly;
• a cartridge including a plurality of fasteners disposed therein, the cartridge being removably loadable into the receiving channel of the mounting portion;
• and
• a locking mechanism disposed within the mounting portion for locking the surgical loading unit to the adapter assembly, the locking mechanism being operably associated with the cartridge such that loading the cartridge into the mounting portion moves the locking mechanism into a locked position and unloading the cartridge from the mounting portion moves the locking mechanism into an unlocked position.

A method of securing a surgical loading unit to an adapter assembly, the method comprising:

• positioning a surgical loading unit, that is free of a cartridge, and an adapter assembly along parallel longitudinal axes such that mating surfaces on a proximal end of the surgical loading unit and on a distal end of the adapter assembly are aligned along a transverse axis;
• sliding at least one of the surgical loading unit and the adapter assembly along the transverse axis to join the mating surfaces and align the surgical loading unit and the adapter assembly along a common axis;
• and
• loading a cartridge within a cartridge jaw of the surgical loading unit to move a locking mechanism of the cartridge jaw from a biased, unlocked position in which a rod of the locking mechanism does not extend proximal of the mating surface of the surgical loading unit to a locked position in which the rod extends proximal of the mating surface of the surgical loading unit and into a recess defined within the distal end of the adapter assembly to lock the surgical loading unit to the adapter assembly.