To obtain a quality finished product, the bend angles must not only be precise but also consistent along the entire sheet length. This means that the table and top beam (hence top and bottom tooling) must be parallel along their entire length during bending. DYE has designed an active system to enable this to happen during folding and it is adjusted for each fold by the controller automatically. This DYE system is known as the Anti Deflection System or ADS for short. This system guarantees much greater precision than the traditional passive systems of shimming with paper or the use of an intermediate beam with compensation by wedges.

With the DYE ADS crowning system the bottom beam of the press brake is constructed as a sandwich assembly (Diagram 1). It consists of two outside plates (A1 and A2) and an inside plate (B). These 3 plates are pinned together at the ends, (not welded which increases the risk of cracking). The table, on which the bottom tool rests, is only attached to the inside plate (B). Specially designed hydraulic crowning cylinders are applied between the outside plates (A1 and A2) and the inside plate (B). The outside plates support the cylinder bodies, while the piston rods apply force to the inside plate. Each hydraulic crowning cylinder is connected via a special crowning valve and the pressure is set by the controller according to the fold. Intervention by the operator is unnecessary, eliminating the time consuming act of shimming the tooling.

Keel Requirements

Larger press brakes require a keel as part of the bottom beam rigidity. ADS, on some of these machines, will eliminate the need for the keel and thus eliminate the need to cut a slot in the workshop floor. (Please refer to chart on the Selecting a Press Brake section for press brake keel requirements.)

With the electromechanical crowning system the operator obtains perfect control of all parameters. This system is available as an option with all DYE press brakes. The crowning device, which is built into the table, consists of a set of double wedges, or waves, that are moved in relation to each other (Diagram 2).

This crowning system is electromechanical: the central pre-loading is automatically calculated by the numerical controller. As for ADS, the controller uses data such as sheet thickness, die opening and material tensile strength which are entered into the controller so that the bending force and related deflection are automatically determined. In this way the optimum crowning is obtained for each bend.