The Force Modulator™ System is built around a series of
interconnected hydraulic cylinders. As the press cycles, the piston
is driven down into the cylinder, in turn ejecting hydraulic fluid
from the cylinder. As the press upstrokes, the fluid is re-pressurized
and released back into each cylinder, forcing the piston to rise
into a fully extended position. It is a standard hydraulic loop.
There is an additional feature that makes this system unique. Each cylinder has a proprietary control device that allows for changing resistance throughout the stroke. In short, stroke tonnage can be controlled at any point in the stroke. This means that each cylinder can start with virtually no resistance tonnage (the equivalent of pre-acceleration); can increase tonnage rapidly to set the bead; and can drop tonnage during part formation. Any other tonnage profile is also possible. When the press upstrokes, the initiation of system re-pressurization and the timing of re-pressurization allow control of the piston and binder return.
This system also allows for zone control. If required, the tonnage profile of each cylinder can be independently controlled. This means that increased or decreased tonnage at each point on the binder ring is now within the grasp of the press owner/operator. Zone control is exerted through the control device found in each cylinder.
Proof is in the results. In a production application at Ford Motor, very high impact and return shocks were all but eliminated, pressure during part formation was all but equalized at each point in the stroke, and measured part quality improved approximately 86% with use of the Force Modulator™.