Nescio si invenisti plerumque compositiones cochlearum habere fullonum et vere fullonum, pleraeque sunt caput sartagines et caput cylindricum, caput cochlearum calculi basically sine lavatoribus. Credo esse clientes qui hanc quaestionem intellegere volunt, ideo artifices cochleae tecum de munere fullonis et fontis fullonum loquentur;

1. Partes plana washer;
① Auge contactum aream inter stupra et machinam;
② Damna superficiei machinae eliminare cum ANISOCYCLUM fons fullonum est exonerare. Cum usus est, ver uti necesse est primo, tum fullonibus utetur. Plana elementum machinae superficiei Proxima est, verque inter fullonem et nucem est. Plana washer augebitur vis area cochleae, munus fullonum fontis est, ne cochleae laxent, potest quiddam agere cum vi applicata.

2. Munus veris spacer
Cum vere fullonibus adhibetur, nucem tensis adstringens, fons nucem elasticam vim dat ut nucem constringat, ita ut nux non facile defluat.

(2) Fere si veris usus es, non fullonibus uteris, nisi quod fastigium et superficiei summa tuetur, simul utetur fullonibus et ver.
(3) Flat washer is generally used to connect soft accessories and hard & brittle accessories. Its main function is to increase the contact area, disperse pressure, then will can protect the soft accessories.
You had known what flat washer and spring spacer do, I think you also know Why don't countersunk head screws need to be used with flat and spring washer together. Countersunk head shape are tapered, but flat washer and spring spacer are uneven, so flat washer and spring spacer are not used. Generally, the countersunk head screw will be screwed into the 90° conical countersunk hole, and the flat washer and spring spacer can’t be used.