US Patent 7357010 Plug assembly for a door lock

A plug assembly has a cylindrical barrel portion, a plug, a driving shaft and a mounting cap. The cylindrical barrel portion has a rear end and a stop. The plug is mounted rotatably within the cylindrical barrel portion. The driving shaft is mounted securely on the rear end of the plug, rotates simultaneously with the plug and has a body. The body is attached to the rear end of the plug and has a non-circular cross section, a rear end and a driving hole defined coaxially in the rear end of the body of the driving shaft. The mounting cap is mounted around the driving shaft and has a front end and a limiting notch defined in the front end of the mounting cap. The stop on the cylindrical barrel portion is received in the limiting notch in the mounting cap.