The "New Wave" For Workholding

While walking the aisles at the recently completed EMO Machine Tool Exhibition in Hanover, Germany, I had an opportunity to talk with Jerry Gagnon, the North American sales manager for Italian workholding manufacturer Tecnomagnete. Mr. Gagnon, who is based in the company's U.S. facility in Troy, Michigan, explained that the company has been actively involved in the U.S. market for the past 7 years, primarily focusing on the moldmaking industry.

Recently the company began promoting a system for milling applications. The Quadsystem magnetic chucks are Tecnomagnete's proposal for all machining operations on milling machines and machining centers. They are easily installed on any type of machine, they do not overheat, and being insensitive to any possible electrical breakdown, they are intrinsically safe. In fact the "electro-permanent" technology used requires the electrical feeding only for a few seconds to energize and de-energize the magnetic field, then the connection can be removed while the chuck will keep the workpiece safely clamped for an indefinite period of time with all the clamping power needed.

Back in the early '70s Tecnomagnete developed a permanent magnetic system that was activated by a quick electric input: just a short burst to "flip the magnet switch." Not needing a constant flow of electricity to maintain the magnetic clamping power, this new system provided the safety margin that had limited the use of magnets in the machining environment in the past. The workholding strength remains constant for an indefinite period of time and is not affected by interruptions to the power supply. The same short burst of electric power is used when the machine cycle is complete and the part is ready to be removed from the machine.

The original self-shimming system, composed of some mobile pole extensions, makes it possible to drastically reduce the setup times—even with workpieces having warped surfaces—and to raise the component above the chuck surface for through-hole machining operations.

These innovative sliding pole extensions allow the machine operator to uniformly support the workpiece even with warped surfaces, achieving high accuracies of planarity. No compression or deformation is made on the workpiece, and the absence of machining vibrations reduces the tooling consumption and improves the finish. The workpiece can be conveniently set up on a bed of fixed pole extensions for contouring and through-hole machining. Due to the fact that the clamping area corresponds to the contact surface, the workpiece is totally free for the full machining on five faces in a single setup.

The square poles of the system's double-magnet circuit allow the unit to obtain the highest concentration of force, and the grid enables the system to safely hold any shape of workpiece. The "neutral crown" system leads the magnetic fluxes totally to the active surface of the chuck with perfect insulation from residual magnetism.

Mr. Gagnon continued by explaining that the absence of machining vibrations allows the Quadsystem to grant high accuracy and to increase the life of the tools and the machine itself. Large workpieces can be fitted on the machine table, thus exploiting all of the machine capacities. A dedicated control unit equipped with a digital remote push-button performs the quick activation and deactivation cycles (Mag/Demag). Advanced safety devices detect the magnetic flux and interfaces with the machine control.

Tecnomagnete can provide a solution for agile production and a real improvement of the efficiency and productivity level on a large variety of machine tools providing semi-finished or rough ferrous parts.