The safety couplings work exclusively with specially selected disk springs with a pronounced degressive characteristic (see figures 3 and 4). This advantage guarantees shortest switching times (2 – 4 msec) and a low residual torque, less than 5% in a disengaged state. The coupling disengages immediately when the cut-out torque is exceeded.

Figure 3

Figure 4

The torque drops immediately to a small residual value, typically 2 to 5%. The switching work required of our couplings corresponds to only a fraction of that of conventional safety couplings with progressive characteristic (see figure 3). This is a decisive advantage because even ultra-short surges in speed are rendered harmless by the safety coupling.

Adjustment of the cut-out torque
Autogard backlash-free safety couplings are delivered with set cut-out torque. There are two possibilities for this, namely:
1) The user/operator names the cut-out torque in his order.
2) The coupling is set on the lowest cut-out torque in its torque range.

Figure 5 shows the spring travel we use for our safety couplings.
Point A stands for the highest spring force = highest cut-out torque.
Point B stands for the lowest spring force = lowest cut-out torque.

Note! The spring travel corresponds approximately to three-quarters of a revolution of the set collar. Every required cut-out torque is progressively adjustable.

Figure 5

Due to the degressive characteristic, the cut-out torque is reduced when the set collar is turned in a clockwise direction (towards min.) and raised when turned in an anti-clockwise direction (towards max.). Note! The set collar may only be turned between min. and max.!

Figure 6