Part traceability is becoming increasingly important in the automotive industry. With this in mind, U.S. Manufacturing (Detroit) recently implemented a laser marking system from Columbia Marking Tools Inc. (CMT-Chesterfield Township, MI) to create 2D codes on its cast-iron automotive differential cases.

The new marking machine employs a 20-watt Sun-Matrix high-speed laser marking head, which permanently marks both 2D Data Matrix codes and part numbers on the machined surface of each differential.

Configured as a stand-alone system, the marker is supported by a welded steel machine base and cabinet, with a steel plate on top to support part fixturing. Also mounted on this plate are an enclosure and a pneumatic lift mechanism, which lowers each part into the actual marking position where an orienting and locating device clamps it into place.

In operation, a robot is typically used to load and unload each part. However, a selector switch on the machine allows it to be set so that it can be safely loaded and unloaded manually. The CMT fiber laser marking head and an In-Sight 5100 Series matrix 2D vision verification camera from Cognex Corp. (Natick, MA) are located in a Class I laser enclosure to ensure worker safety.

To reduce the machine’s footprint, the system’s verification camera, laser controller and PLC are all located in a control cabinet set in the machine’s base. This cabinet is equipped with a dedicated heat exchanger to accommodate the harsh working conditions at U.S. Manufacturing, which can include temperatures in excess of 100 F.

To facilitate accurate marking, the laser features a lower power setting, similar to an ordinary laser light pen, which allows operators to visually verify the light path prior to actual marking.

The machine is also equipped with proprietary PCS-2000 machine control, which has been specifically developed for applying Unique Identification and 2D matrix codes in applications employing automated electronic mark verification.

The system’s touch-screen monitor and processor are mounted in a standard NEMA 12 enclosure.

For more on machine vision verification, call 508-650-3000 or

For more on parts marking, call 800-469-MARK or visit