Pincers-type gripper for seizing objects and gripping head equipped with such grippers

A gripper for seizing elongated objects such as bottles, the gripper comprising:

• stationary support means having a central axis extending between a clevis end portion and an opposite end;
• a set of jaws hingedly mounted in said clevis end portion, each jaw being rotatable between an open position and a shut position about a respective pivot axis spaced from and lying in a plane perpendicular to said central axis;
• an operating rod slidably disposed in said stationary support coaxial with said central axis, said operating rod having a first end portion extending between said jaws and a second end portion;
• an actuating member fastened to said operating rod adjacent said first end and extending transversely to said rod, each of said jaws having an aperture loosely receiving said actuating member, the actuating member having two lateral contact surfaces parallel to each other, and the aperture of each jaw having a planar opening cam surface and an opposed planer closing cam surface, said cam surfaces being non-parallel and extending at an angle such that said opening cam surface is parallel to the contact surfaces of the actuating member when the jaws are in the open position and said closing cam surface is parallel to the contact surfaces of the actuating member when the jaws are in the shut position;
• stop means fixed on said operating rod;
• and
• spring means disposed between the stationary support means and said stop means and urging the operating rod in the direction such that one contact surface of the actuating member bears against the opening cam surfaces of said jaws for urging the jaws to said open position.