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Automatic pre-feeder with selective sheet flipping robot for digital printing lines


Why a robot pre-feeder?

The design of the gripper - patented by SERRA - and its movement with the robotic arm enables the option of flipping the boards or not when required. This functionality opens many possibilities and responds to a market demand. Normally, the stack of corrugated boards comes printable side down, which is supposed to be the outer side of the box. Therefore, we will need to flip the boards before printing because the digital presses always print on top. However, sometimes, on some jobs, it may not be necessary to flip the boards to print the inside face of the box.



The Robot Pre-feeder can be installed at the initial stage of the installation along with the basic printer line or in a second stage as an upgrade

to convert the line from manual mode to fully automatic. The upgrade allows for a volume increase in productivity comfortably with a reduction of 1 or 2 operators and minimal exposure to security risks. Therefore, the return on investment of such equipment is calculated to be between 2 and 3 years. The Robot Pre-feeder increases the productivity of the digital printing line with a fully automatic operation at high speed ensuring efficiency and operator safety.

The innovative design is composed of independent bodies that enable a very flexible configuration in which the installation can be customized according to the plant's supply logistics system and the available space. The Infeed Table receives the stack of boards and places them in the center. Once the stack is centered, it is picked up by the Bundle Breaker whose frame moves up and down to reach the top position of the stack, where it separates a bundle from the stack and pushes it into the gripper. The transition between the Bundle Breaker and the Gripper is through overlapping belts that guarantee a gentle handling of the boards and does not damage them. The Gripper and the Robot are the key elements to achieve the advantages mentioned above. The Roller Table squares and places the bundles. When using the dual line feed function on the feeder, the bundle is positioned accordingly. The Telescopic Table moves the stack towards the feeder through a flow of shingles allowing for a friendly and gentle handshake between the Pre-feeder and the Feeder. The movement of the Telescopic Table is motorized and can be adjusted according to the length of the sheet format.



SERRA, global provider of solutions for the corrugated industry

Since its inception in 1984, the SERRA family business has been an innovator and global provider of machine solutions that have been key to the corrugated cardboard industry and have positioned it as an international reference manufacturer. SERRA helps its customers achieve higher quality and productivity by optimizing workflows with lower operating costs thanks to two main competitive advantages: local technical support and its innovative solutions that often redefine market standards, including The die-cutting solutions, peripheral equipment and installed bases for digital printing and the manufacture of auxiliary equipment stand out.


Currently, the brand is positioned as one of the main players in the corrugated cardboard industry, not only at the design and manufacturing level, but also due to its global coverage in the application of high-tech solutions to optimize workflows. and as a partner in digital printin