C-W indicator

grabcad

The proposed method utilizes two lasers with sensors attached to their housing. When a chain is under load, its length reaches maximum, allowing for measurement via this process: as the first laser (on the left) nearly stops transmitting its signal to the sensor, the second laser is already 3.86mm ahead on the appropriate chain link. This 3.86mm denotes the vital elongation needed in this setup. A 7x20 chain was used, resulting in a total length of (9 x 20 pitch) + (7 link thickness) + (6 spacing within one link (remaining space from 20-7-7)) = 193mm. Multiplying 193 by 0.02 gives the critical elongation, which is 3.86mm. The concept's core principle is that when sensor number 1 is about to cease receiving a signal from the laser, sensor number 2 should already be off. If sensor number 2 is on at this moment, it indicates the chain has reached its critical elongation of 3.86mm (or any other specific value). Two sensors can be logically connected so that when the chain reaches its critical length, their outcome can be 1 (send electrical signal) or 0 (stop sending an electrical signal). You may choose whether to use a 1 or 0 signal for further manipulation, such as automatically setting the brake and halting the lifting process or simply alerting the operator that the chain needs replacement. This concept can also be adapted if the chain links are in linear order instead of on the sprocket. Happy experimenting!