Surgical instrument with lockout mechanism

A surgical stapling instrument comprising:

• first and second jaws;
• a drive member configured to translate in a distal direction through at least one of the first and second jaws;
• a locking member pivotable between a first position permitting distal translation of the drive member, and a second position preventing distal translation of the drive member, wherein the locking member includes a ramped surface;
• wherein at least one of the first and second jaws includes a channel configured to receive a staple cartridge, the channel including at least one sidewall and a bottom wall, the bottom wall including at least one opening, the staple cartridge including a ramped surface configured to engage the ramped surface of the locking member to maintain the locking member in the first position;
• and
• wherein the locking member includes at least one foot configured to engage said at least one opening in the bottom wall of the channel.

A surgical stapling instrument comprising:

• first and second jaws, at least one of the first and second jaws including a channel defining a longitudinal axis, having at least one side wall and a bottom wall and being configured to receive a staple cartridge, the bottom wall including at least one opening;
• a drive member configured to in a distal direction through at least one of the first and second jaws;
• and
• a locking member pivotable between a first position permitting distal translation of the drive member, and a second position preventing distal translation of the drive member, the locking member including a pair of arms, each arm having a surface configured to engage and align the drive member along the longitudinal axis of the channel as the drive member translates distally between the arms of the locking member, and
• wherein the locking member includes at least one foot configured to engage said at least one opening in the bottom wall of the channel.