Screw fastening system and screw fastening device

A screw fastening system comprising:

• a SCARA robot having a first arm at a base and a second arm on a leading end side that is connected in series to the first arm;
• a leading end shaft that is provided in the second arm and is driven to move along an elevation axis that is an output shaft of the second arm by a driving means of the second arm;
• and
• a screw fastening device that is fixedly provided in a casing of the second arm in a screw fastening axis that is different from the elevation axis and parallel to the elevation axis;
• wherein
• the screw fastening device includes
• a screw fastening driving means fixedly provided in the casing of the second arm,
• a drive shaft rotationally driven by the screw fastening driving means,
• an extension bar that is so connected to rotate together with the drive shaft in a circumferential direction of the screw fastening axis and to move in an axial direction of the screw fastening axis, and is provided with a tool at a tip of the extension bar, and
• a sliding member that is fixedly connected to the leading end shaft and supports the extension bar so as to move together in the axial direction and be rotatable relatively in the circumferential direction, and
• movement drive of the leading end shaft causes movement drive of the extension bar in the screw fastening axis, and a screw of a workpiece fitted to the tool is rotated by rotation drive of the screw fastening driving means.

A screw fastening device fixedly attached to a casing of a second arm of a SCARA robot, the SCARA robot having a first arm at a base and a second arm on a leading end side that is connected in series to the first arm and has a leading end shaft, and the leading end shaft being driven to move along an elevation axis that is an output shaft of the second arm by a driving means of the second arm, the screw fastening device comprising:

• a screw fastening driving means fixedly provided in the casing of the second arm;
• a connecting member that fixedly connects the screw fastening driving means to the leading arm so that a screw fastening axis parallel to the elevation axis serves as a rotation axis of the screw fastening driving means;
• a drive shaft rotationally driven by the screw fastening driving means;
• an extension bar that is so connected to rotate together with the drive shaft in a circumferential direction of the screw fastening axis and to move in an axial direction of the screw fastening axis, and is provided with a tool at a tip of the extension bar;
• and
• a sliding member that is fixedly connected to the leading end shaft and supports the extension bar so as to move together in the axial direction and be rotatable relatively in the circumferential direction;
• wherein
• movement drive of the leading end shaft causes movement drive of the extension bar in the screw fastening axis, and a screw of a workpiece fitted to the tool is rotated by rotation drive of the screw fastening driving means.