Gas spring-powered fastener driver

A gas spring-powered fastener driver comprising:

• a cylinder;
• a moveable piston positioned within the cylinder;
• a driver blade attached to the piston, the driver blade movable with the piston between a ready position and a driven position;
• a lifter including a rotary component operably coupled to the driver blade to move the driver blade from the driven position to the ready position;
• and
• a multi-stage planetary transmission including
• an output shaft operatively coupled to the lifter to provide torque thereto,
• a first bearing supporting a first portion of the output shaft for rotation,
• a second bearing supporting a second portion of the output shaft for rotation, and
• first and second planetary stages;
• a housing including a cylinder support portion in which the cylinder is received and a transmission housing portion in which the first and second bearings are received to rotatably support the output shaft and in which the first and second planetary stages are located;
• a motor;
• and
• a motor output shaft operably coupled to an input of the multi-stage planetary transmission to provide torque to the transmission,
• wherein the cylinder support portion and the transmission housing portion are integrally formed as a single piece,
• wherein the rotary component includes a body and a plurality of engagement members engageable with teeth on the driver blade to return the driver blade from the driven position toward the ready position, and
• wherein at least a first of the engagement members is movable relative to the body of the rotary component in response to contact with a corresponding tooth on the driver blade.