Mechanism for rotating an object over a determined angle about a vertical axis

In a strapping machine which includes a strapping mechanism and a conveyor system for rectilinearly moving objects to and away from said strapping mechanism, the strapping mechanism being operative in a vertical plane which is perpendicular to said rectilinear direction of movement of said objects, the improvement wherein said conveyor system includes a working surface and four openings extending therethrough, two of said four openings being located on one side of said vertical plane and the remaining two of said four openings being located on the opposite side of said vertical plane;

• and wherein an object-turning mechanism is operatively positioned below the working surface of said conveyor system, said object-turning mechanism including a support frame, four rollers mounted on said support frame, said four rollers being positioned to be simultaneously positionable in a respective one of said four openings in the working surface of said conveyor system, each roller being rotatable about a horizontal axis and oriented so as to be tangent to the circumference of a common circle, two endless belts for rotating said four rollers in the same direction with respect to the circumference of said common circle, a first of said two endless belts driving a first pair of said rollers which are located on respective opposite sides of said vertical plane and a second of said two belts driving the second pair of said rollers which are located on respective opposite sides of said vertical plane, and means for moving said support frame vertically upwardly and downwardly such that at least a portion of each of said four rollers can be located in an active position above the working surface of said conveyor system or in an inactive position below said working surface.