Gripping mechanism and transportation article conveyance device

A gripping mechanism attached to a moving body so as to grip and convey a transportation article, comprising:

• a rotating body provided so as to be rotatable about a rotation axis, the rotating body including a pinion on which a pinion gear is formed;
• a first arm and a second arm disposed so as to be separated from the rotation axis by the same distance, with the rotation axis as a center, in order to grip the transportation article;
• and
• a width adjusting mechanism which engages with the rotating body, the first arm and the second arm and which is configured such that the first arm and the second arm move toward the rotation axis in the case where the rotating body rotates about the rotation axis in a predetermined direction, and the first arm and the second arm move away from the rotation axis in the case where the rotating body rotates about the rotation axis in a direction opposite from the predetermined direction, the width adjusting mechanism including a first rack on which a first rack gear meshing with the pinion gear is formed and which is connected with the first arm, and a second rack on which a second rack gear meshing with the pinion gear is formed and which is connected with the second arm;
• a locking means for suppressing movement of the first arm and the second arm away from the rotation axis, the locking means including:
• a first engagement portion that engages with the first rack, a second engagement portion that engages with the second rack, and an elastic member for pressing the first rack and the second rack in a direction perpendicular to moving directions of the first arm and the second arm by the first engagement portion and the second engagement portion,
• wherein a first vertical surface, which faces a direction in which the first arm moves toward the rotation axis, is formed on the first engagement portion,
• a second vertical surface, which faces a direction in which the second arm moves toward the rotation axis, is formed on the second engagement portion,
• a plurality of surfaces that face a direction in which the first arm moves away from the rotation axis to oppose the first vertical surface are periodically formed on the first rack, and
• a plurality of surfaces that face a direction in which the second arm moves away from the rotation axis to oppose the second vertical surface are periodically formed on the second rack.