Chủ Nhật, 10 tháng 3, 2013

Knitting elements on tricot machines


1. Guides and guide bars

Guides are thin metal plates drilled with a hole in their lower end through a warp end may be threaded if required. The guides are held together at their upper end in a metal lead of 1 inch width and are spaced in it to the same gauge as the machine. The leads in turn are attached to a horizontal bar to form a complete guide bar assembly bar, so that the guides hang from it with each one occupying a position at rest midway between two adjacent needles. In this position the needles do not receive the warp yarns.
The needles only receive the warp yarns in their hooks if the guides wrap or lap the yarns across the needles. For the purpose, the guide bars are given a compound lapping movement. All guides in a conventional guide bar produce an identical lapping movement at the same time and therefore have requirements of same warp tension and rate of feed although yarns may differ in colour and composition. But the two guide bars may have different lapping movement where requirement of warp feed and warp tension may vary also.

2. Needle and needle bar

In warp knitting, all the needles move up and down together for loop formation, i.e., all the loops in a course are made simultaneously. So all the needles are connected/fixed to a bar called needle bar and the needle bar is lifted up and lowered down by means of a cam fitted outside the machine, generally at the driving side. Needles are set in tricks cut in the needle bed of the machine.

3. Closure bar (or Presser bar)

 In order to close the hook for casting-off of the old loop in Tricot machine, some closing element (Presser bar) is must. The elements needed in Tricot machine are set in a separate bar across the full width of the machine which also get motion from a cam or crank fitted on the main shaft. The presser bar closes the hook of the needle when the same moves downward after catching of the new yarn for loop formation.

4. Sinker and sinker bar

The sinker is a thin plate of metal which is placed between every two needles. The sinkers are usually cast in units, 1 inch long, which in turn are screwed into a bar called sinker bar. The sinkers are given almost linear horizontal (forward and backward) motion through the sinker bar. The drive generally comes from a crank or eccentric arrangement. The neb and the throat of the sinker are used to hold down the fabric while the belly of the sinker is used as a knocking over platform.

Không có nhận xét nào:

Đăng nhận xét

Please leave your comments here to help in improving post. Thank you!