I mentioned the role of the relaxation device in a previous article, but each relaxation device has a suitable textile structure.
Positive relaxation device
The positive relaxation device positively moves the tension roller to correct the difference in warp tension between A when the warp is open and B when the warp is closed.
This device is basically suitable for plain weave. It is not suitable for anything other than plain weave.
In plain weave, all warp threads move up and down with each thread insert, but not all threads except plain weave move with each thread insert.
Therefore, instead of absorbing the tension difference, it puts an unnecessary load on the thread.
No positive relaxation device (Negative relaxation device)
In order to absorb the difference in warp tension between A when the warp is open and B when the warp is closed, the tension roller 1 is passively corrected by the buffer of the spring 2.
Negative relaxation device is the one that keeps the tension as a whole, and this device is suitable for other than plain weave. Not suitable for plain weave. It’s not that plain weave can’t be woven.
The reason is that the tension difference is canceled by the spring, so it feels like the thread stretches when compared. Then, it may cause a poor opening.
Therefore, we think that it is not particularly suitable for high-speed weaving and plain weave.