The anti-overload-coupling is designed as a safety device
If the drive system (electric or manual) is in motion, there is much "momentum" in the system (kynetic energy). If , for one reason or another, the press bed blocks, all this energy is suddenly released, resulting in damage to the rollers and/or the mechanical drive system. To avoid this from happening, the press is equipped with the anti-overload-device.
One can find this device built-in in the main gear wheel. If the steel cover is taken off, the wheel and the anti-overload-device are clearly visible. The device is actually nothing more or less than a friction coupling; and consists of disks of a fiber like material and steel disks.
By raising the pressure on these disks the torque that this device can transfer is raised. For this purpose, the outher ring (visible on the image above) is fitted with four hexagon screws. By tightening these screws the pressure between the disks is raised and so is the torque.
The printer will have to adjust this coupling in relation to the torque he needs to work properly. A bigger print requires a different setting then a small print. It is important to set this correctly. If one sets it only for correct work with big prints, it might lead to damage if this setting is not adapted when printing small prints, and a sudden blocking occurs.