Method, apparatus and plant for manufacturing shell structures
According to the invention, a shell handling carriage ( 19 ) is provided with grippers ( 194 ) which grip the end edges of a shell ( 2 ) made of composite material still fixed to a molding drum ( 11 ). An expeller strut ( 13 ) prevents the drum ( 11 ) from moving while the carriage ( 19 ) translating 5 removes the shell ( 2 ) from the drum ( 11 ). The shell ( 2 ) is then transported by the carriage ( 19 ) to a working station in which robots rivet the transversal ribs on it. The transversal ribs reach the robot working position orderly arranged on a self-moving rib store, which is inserted in the shell ( 2 ) itself.
1. A gripping device ( 194 , 19 ) for manufacturing shell structures ( 1 , 1 ′) comprising a raw shell ( 2 , 2 ′) having at least one edge ( 20 A, 20 B, 20 A′, 20 B′), the gripping device ( 194 , 19 ) comprising:
a handling carriage ( 19 ) by means of which the gripping device can move together with a shell structure loaded on the gripping device; and at least a blocking gripper ( 194 ) associated to the handling carriage ( 19 ) and arranged for gripping the raw shell ( 2 , 2 ′) by gripping said at least one edge ( 20 A, 20 B, 20 A′, 20 B′), wherein the handling carriage is further provided with an annular structure and the blocking gripper comprises a fixing frame fixed to the annular structure, and a movable base hinged to the fixing frame so as to be able to rotate about a rotation axis which is parallel to the plane in which said fixing frame lies.
2. The device according to claim 1 , further comprising a fixing opening ( 192 ) through which the shell ( 2 ) passes through, wherein a plurality of the blocking grippers are disposed around and/or near to the fixing opening ( 192 ) so as to fix the raw shell ( 2 , 2 ′) to the device while it is loaded on the device, by gripping at least part of the edge ( 20 A, 20 B, 20 A′, 20 B′) of the shell ( 2 ).
3. The device according to claim 1 , wherein the raw shell ( 2 , 2 ′) has a substantially tubular shape and defines two open ends and two end edges ( 29 A, 20 B) at the open ends, and the blocking grippers ( 194 ) are positioned in a triad of Cartesian axes to fix the raw shell ( 2 , the 2 ′) on the device by blocking the two end edges ( 20 A, 20 B) of the raw shell ( 2 ).
4. The device according to claim 1 , wherein the raw shell ( 2 ′) has substantially the shape of a cylindrical sector ( 2 ′) or cone sector or frustum of cone sector, and defines a curved end edge ( 20 A′, 20 B′), and a side edge ( 68 ) having a curvature less pronounced than the end edge ( 20 A′, 20 B′), and the blocking grippers ( 194 ) are positioned in a triad of Cartesian axes to fix the raw shell ( 2 ′) on the gripping device so as to block the end edge ( 20 A′, 20 B′) and the side edge ( 68 ) of the shell ( 2 ).
5. The device according to claim 1 , further comprising a rotary actuator for the handling carriage ( 19 ) and arranged for rotating a raw shell ( 2 ) on the handling carriage, while the raw shell ( 2 ) is on the gripping device ( 194 ) and blocked by the blocking grippers ( 194 ).
6. The device according to claim 1 , further comprising a toggle mechanism that rotates the movable base around the rotation axis.
7. The device according to claim 1 , wherein the blocking gripper comprises a pair of jaws attached to the movable base, at least one of said jaws being a movable jaw.
8. The device according to claim 7 , wherein the movable jaw is arranged for rotating and translating in a plane defined by a radial direction and a center direction defined with respect to the annular structure so as to clamp the raw shell in the thickness direction of the raw shell.
9. The device according to claim 7 , wherein the blocking gripper is arranged to be being opened and closed by the rotation and translation movements performed by the movable jaw.