The sinker is the second primary knitting element (the needle being the first).It is a thin metal plate with an individual or a collective action operating approximately at right angles from the hook side of the needle bed, between adjacent needles.
Primary knitting elements:Three primary knitting elements:
Needle: Latch needle, Spring bearded needle & Compound needle.
Cam: Knit cam, Tuck Cam, Missed cam
Sinker: Holding down sinker, Knocking over and loop forming sinker
Main parts and their functions of latch needle
The hook: Grasping a new yarn in the process of knitting i.e. the hook which draws and retain the new loop.
The latch: Freely rotating around the axle and tightly closing the hook owing to the spoon located at the end of the latch.
Knitting is a technique to turn thread or yarn into a piece of cloth. Knitted fabric consists of horizontal parallel courses of yarn which is different from woven cloth. The courses of threads or yarn are joined to each other by interlocking loops in which a short loop of one course of yarn or thread is wrapped over the another course.
The optical method measures the variations in diameter of a yarn and not in its mass. The instrument an infra-red transmitter and two identical receivers. The yarn passes at speed through one of the beams, blocking a portion of the light to the measuring receiver. The intensity of this beam is compared with that measured by the reference receiver and from the difference in intensities a measure of yarn diameter is obtained.
The roving coming out of the front delivery roller is threaded through the top of the flyer, passes through its hollow leg around the presser arm on to the bobbin. The purpose of providing twist in roving is to give the strand sufficient strength to withstand the strain during unwinding in the creel of the ring frame. The insertion of twist is achieved by the rotation of the flyer.
Shaded twill is formed shade effect on the surface of the fabric. The shade effect is created by the combination some thick to thin twills and thin to thick twills. Stepped twill is formed by steeping a continuous twill and keeping the direction of twill line same or opposite.
Elongated twill is constructed by advancing the points of intersection two or more threads in one direction and one thread in the other direction.On the other hand combined twill is formed by combination two regular twill and arranging them alternately with each others.
The drafting section of the roving frame may be 3 over 3 or 4 over 4 with or without apron roller arrangement. Only the 3-over-3 or 4 over 4 roller with double apron drafting system are still to be found in modern machines offered by manufacturers. In general 3/3 drafting system is used, but for higher draft applications 4/4 drafting system is used.
Yarn number is a measure of the fineness or size of a yarn expressed either as mass per unit length or length per unit. Yarn Count and Yarn Size are synonymous with Yarn Number.There are two systems of expressing yarn number or yarn count.
❶ Direct yarn numbering system (mass/unit length)
❷ Indirect yarn numbering system (length/unit mass)