Machine for covering packaging boxes

1. A machine for covering a packaging box with a glued sheet, comprising a first covering head and a second covering head, said first covering head having a first presser and a first folding blade, said second covering head having a second presser and a second folding blade, each of said first presser and said first folding blade being movable horizontally in a direction towards a box to apply a glued sheet to a corresponding first sidewall of the box, each of said second presser and said second folding blade being movable horizontally in a direction towards the box to apply the glued sheet to a corresponding second sidewall of the box, each presser having a contact surface, each covering head being adjustable in vertical position so that each presser and each folding blade is adjustable in vertical position, each presser being repositionably settable (a) in a first position where its contact surface defines a vertical plane and (b) in a second position where its contact surface defines the same vertical plane but has been rotated about a horizontal axis perpendicular to the vertical plane, each folding blade having a planar working surface terminating in a working edge and having a longitudinal axis substantially parallel to the working edge and a transverse axis perpendicular to the longitudinal axis and parallel to the planar working surface, each folding blade being repositionably settable (a) in a first position where its planar working surface is oriented horizontally and (b) in a second position where (i) its planar working surface is oriented at an angle oblique to the horizontal and (ii) its transverse axis is oriented horizontally, so that (a) in a first position, the machine can use the first presser and the first folding blade to apply a glued sheet to a sidewall of a box, the sidewall being defined by a pair of vertical corners, the vertical corners being of the same length so that the sidewall therebetween has a top edge oriented horizontally and (b) in a second position, the machine can use the first presser and the first folding blade to apply a glued sheet to a sidewall of a box, the sidewall being defined by a pair of vertical corners, the vertical corners being of different lengths so that the sidewall therebetween has a top edge oriented at an angle oblique to the horizontal.

2. The machine of claim 1 , wherein the first covering head is independently rotatable about a first vertical axis of rotation, and wherein the second covering head is independently rotatable about a second vertical axis of rotation.

3. The machine of claim 1 , wherein the first presser is mounted on an adjustment block that can (a) move horizontally, (b) rotate about a horizontal pin, and (c) be fixed in angular position.

4. The machine of claim 3 , wherein the first folding blade is mounted on an adjustment block that can (a) move horizontally, (b) rotate about a horizontal pin, and (c) be fixed in angular position.

5. The machine of claim 4 , wherein the first presser adjustment block and the first folding blade adjustment block are reciprocally mobile and can be adjusted independently of each other.

6. The machine of claim 4 , wherein the first presser adjustment block and the first folding blade adjustment block are mounted on said first covering head.

7. The machine of claim 1 , wherein the first folding blade is mounted on an adjustment block that can (a) move horizontally, (b) rotate about a horizontal pin, and (c) be fixed in angular position.

8. The machine of claim 1 , further comprising a third covering head independently rotatable about a third vertical axis of rotation and a fourth covering head independently rotatable about a fourth vertical axis of rotation.