Patent ID: 7882685

Claim:
A gripper for an automatic bag filling apparatus, wherein a plurality of pairs of grippers are provided at equal intervals around a periphery of a transportation member that rotates continuously or intermittently, and said plurality of pairs of grippers respectively grip both side edges of a bag and are rotated along a predetermined circular path together with said transportation member; each pair of said grippers being comprised of: a pair of left and right swing levers provided on said transportation member, gripper arms of which base end portions are respectively fixed to said swing levers, inwardly-facing chuck sections respectively provided in tip end portions of said gripper arms to face each other, and chuck open/close mechanisms that open and close said chuck sections; each of said chuck sections being comprised of: a fixed chuck element having a gripping part provided at the tip end portion of said gripper arm and faces in an opposite direction from the base end portion of said gripper arm, and a movable chuck element rotatably provided at the tip end portion of said gripper arm; and each of said chuck open/close mechanism opening and closing said chuck section by rotating said movable chuck element; and wherein said gripper arm is in a tubular shape; said chuck open/close mechanism is comprised of: an air cylinder installed inside a tube body of said gripper arm such that a tip end of a piston rod thereof faces toward a tip end of said gripper arm, and a link mechanism in which said tip end of said piston rod of said air cylinder is linked to said movable chuck element within said tube body of said gripper arm; and said movable chuck element is rotated when said piston rod advances and retreats.