Object of the pedal feed motion is to maintain the weight of cotton fed to the beater in a scutcher from feed roller as constant per unit time.
The sheet of cotton is fed to the beater of the scutcher through pedal and pedal roller and pair of heavily weighted feed rollers.
16 pedals are provided below the pedal roller.
They are swinging depending upon the thickness of the cotton sheet.
All the pedals are connected to link system and then to the cone drum regulating box as shown in fig.
Bottom cone drum (driving drum) get power from motor. Top cone drum (driven cone drum) drive the feed roller, through worm gear.
Principle:
Due to the thick and thin places of cotton, the movements of pedals are utilised to change the postiion of the belt in the cone drum by means of levers to change the speed the feed roller according to the thick and thin places of cotton in order to keep the feed constant per unit time.
Working of the pedal feed motion:
If thick layer of cotton is going through pedal roller, the speed of the feed roller is reduced and increased in the case of thin layers of cotton is fed in order to keep the feed constant per unit time.
If a thick layer is going through the pedal ( 1 & 2) roller particular ends would be depressed and these pedals are fulcrumed as shown in fig. This causes the ends A,B,C,G,K,N and P will rise (refer fig.) One end of the common lever is fulcrumed and also dead weight is provided on another side.Because of these, the upward movement of the p will depress X and shift the belt on the smaller end of the driving cone drum (bottom cone) and so decreases the speed of the top cone which drive the feed roller slowly.
Similarly if a thin layers passes through the pedal (no. 1 &
2) the ends A,B,C,G,.K,Nand P will fall and end X will rise and
shift the belt on the bigger end of the bottom cone and so
increase the speed of top cone drum, which drive the feed roller
with fast.
If 'A' rises and 'B' falls equally, the point 'C' remains stationary and no change takes place.
If half the pedal ends moves up and other half down, the centre 'N' is not influenced and no change takes place.
If all the pedals rise at once, the whole system of lever and links move bodily upwards except center M, and it all falls if the pedal ends are all depressed.
The feed roller rotates in the same speed without any variation, when average weight of the cotton sheet fed to the beater is same so pedal feed regulating motion helps to produce uniform weight per yard of lap, and we can get even lap hank with low C.V % of metre to metre lap weight variation.