Automation, higher production and improved quality of the products are the requisite of any recent developments.
Chute feeding is a recent development in feeding small tufts of cotton fibres directly from blow room to a series of cards, arranged in a circuit through ducts and chutes.
Already we have seen the working of chute feeding system in a third unit..
In this unit, we shall discuss some other developments in licker-in section of carding one by one in the following pages.
The objects of major developments in licker in section that have taken place are
To improve the opening of tuft at high rate of feed in H. P card.
To distribute the tufts as evenly as possible on the cylinder.
To extract the maximum trash with minimum loss of spinnable fibres.
Following are the developments that have taken place in the licker-in section.
1. Card analyser
2. Development in place of mote knife
3. shirley modification.
4. Fibre retriever.
Card analyser or uni opener.
M/S. Nagoya a leading card clothing manufacturer of Japan has offered an evener roller under the trade name of card Analyser. This may also be called as uniopener.
As shown in fig, this evener roller is placed above the licker in. It opens the large unopened tufts released by the licker-in and also remove the excess fibres on the cylinder which is returned to the feed roller again through a space provided between the taker-in and its cover.
Thus it helps to feed the tufts as evenly as possible on the cylinder. It is claimed that the neps formation and the waste are reduced.
Development in place of mote knife
M/S. Mafatlal Engineering has introduced comb bar and wast control knife attachment in their super card in place of mot knives, as shown in fig.
The arrangement consists of a small diameter cylinder clothed with coarse pitch wire. It replaces conventional mote knives when processing cotton and is positioned directly under the feed plate nose so that the material feed is immediately subjected to carding action.
This opens the cotton and gives high trash yield by permitting the trash to separate from the main stream of fibre in the large free space following the comb bar.
Shirley modification
The essential changes in the cleaning region are: 1. The replacement of conventional mote knives by a deflector plate which is provided under side of the feed plate.
The taker-in grid is replaced by a shorter grid usually 7" long, incorporating 3 bars and the normal perforations. & The Setting between grid and taker-in is made wider than the conventional card.
A safety guard is fitted under the feed plate to cover the exposed portion of the taker-in.
For short staple cotton 8" grid is usually suitable, for medium 7" grid and for long staple cotton 6" grid may be employed.
Advantages of shirley modification:
The amount of trash passed on to the cylinder was 31% less than normal resulted in cleaner sliver.
The dust generated during carding -is reduced.
The life of the metallic clothing is increased due to less trash on cylinder.
Increases the trash extraction of 10% with 24% less lint loss than conventional card.
Fibre retriver
This arrangement reduce the loss of spinnable fibres.
The nose of the fibre retriever deflects the heavier trash particles, downwards away from the licker-in.
Air drawn in by the fast rotating licker-in is channelled between the buffle plates of fibre retriever, so that the trash particles fall downwards in the up current of air, which detaches any spinnable fibre entangled with the trash particles and carries the good fibres back to the licker-in.
It is claimed that as much as 1 % waste is reduced.
