CAD-CAM in Knitting

8/10/2019 CAD-CAM in Knitting

1/24

BAHIRDAR UNIVERSITY

SEMINAR -2 ON CAD/CAM IN KNITTING

Prepared by; Luwam Bahta

1


2/24

Table of Contents

Introduction CAD/CAM Discipline

CAD/CAM Design Features

Circular Knitting Machine Control

Modern V-bed Knitting Machine Control

Advantages of CAD/CAM in Knitting

2


3/24

Introduction

The CAD/CAM process is a geometric modelof a product under design in which the CAD

process is a subset of the design process and

the CAM process is subset of the

manufacturing process.

Application of computer graphics in knitting

industry CAD/CAM systems has two aspects:

1. Knitting structures design and

2. Design of knitting pattern shapes.

3


4/24

Cont.

Electronic machine eliminates all punch cards,chains, rack wheel, peg drum which are

expensive and bulky.

Interactive computer graphics enables designerdraw pictures and display on the screen. Color

can be added or changed immediately. Pattern

can be rotated, stretched, mirror and scale.

4


5/24


6/24

CAD design feature for knitting

6


7/24

Cont.

7


8/24

Auto, bias and mirror

pattern from CAD design

8


9/24

Color Change and Pattern Composition by

CAD System

9


10/24

CAM feature on color

selection Pattern assemble

10


11/24

Pattern Developing by CAD system

11


12/24

Electronic Circular Knitting Machine

Control

CAD/CAM are mainly used for jacquard single ordouble jersey knitting on large diameter circular

knitting machines. The content of CAM in piece goods

are:

The memory of the controller

The very large memory of the machine built in computer

can hold up a few different patterns, which can be called

up at any time, or mixing of patterns during knitting. Thepreparation of jacquard patterns are normally done on

CAD units and the final patterns are stored in the data

carriers for the knitting machine to read.

12


13/24

Cont.

Shifting of colors on jacquard fabric.

Before knitting, color yarns are placed on the machine inspecified order like

feeder no 1 2 3 4 5 6 7 8

yam color A B C D A B C D

If the same pattern has to be knitted with differentcombination of color such as;

feeder no 1 2 3 4 5 6 7 8 and

yarn color B C DJ A B C D orfeeder no 1 2 3 4 5 6 7 8 and

yam color C D A B C D A B or

feeder no 1 2 3 4 5 6 7 8 and

yam color D A B C D A B C 13


14/24

Principle

Computer

The flexibility of making decision, process data (yes orno) make it ideas for counted loop sequence, branchingor jumping operation.

ie. Electronically controlled knitting pattern preparation

and needle selectionMain Sections of Computer

CPU, Memory, Peripheral Interface

Input & output device

Input: sensors on knitting machine; keyboards, light-pen; tapes and discs.

Output : actuators on knitting machine, light; digital and

graphic display; tapes and printer. 14


15/24

Cont.

Memory: ROM and RAM

Read only memory (ROM), non-volatile, cannot be

erased.

Hold important program and is programmed in

manufacturing.

Read and Write Memory (RAM)

Is volatile and data can be erased.

Use to store data and programme during processing.

Designer can freely explore his/her ideas using the

computer tools 15


16/24


17/24

Modern V-bed Knitting Machine Control

The modern V-bed machines abandoned the pasteboard

card control because:

The electronic parts are cheaper to produce than the

mechanical parts;

Numerical is more accurate and very fast in response;

Programs are easy to file or store;

Easy to duplicate the programs

17


18/24

Numerical and computer control

Numerical Control

They are simple control for non-jacquard knitting. It

contains a control panel with function keys and control

knobs for data input. The major advantages is that no

pasteboard card and hole punching is needed.Computer Control

The numerical control is only good for simple knit

collars, rib straps and body panels without pattern.Once individual needle selection is involved, computer

control must be used.

18


19/24

Cont.

Modern electronic V-bed m/c has :

Central Processing Unit: The brain of m/c control

with data like pattern, machine control, economizer,

pattern development.

Keyboard : This is used for giving command or makemodification.

Tape/Floppy reader : The pattern and data input

device Visual Display Unit : A monitor to display all

information of the knitting machine.

19


20/24

Shima Seika Control System

1. Control tape

Similar to punch card in mechanical machine, it is a one inch paper

tape with 8 row holes. The tape is divided into block, one block is

the same as one punch tape.

2.Pattern tape

This sector contains all the pattern details. The design is normally

created in a CAD system and is now transferred as a series of holes

in the punch tape. The length of tape will depend on the pattern size,

the longer the design, the longer will be the tape.

3.Pattern development tape

This is to control the location of the pattern onto the fabric. It can be

mirror the design or repeat the design horizontal/vertically

20


21/24


22/24

Modern V-bed Knitting Machine

22


23/24

Advantages of CAD/CAM in Knitting

The CAD/CAM system enables the machine toknit the parts (cuts) of products or the whole

products in which;

It allows to avoid cutting the materials Reduces the number of operations

It leads to reduce the waste products to a

minimum.

23


24/24

THANK-YOU!!!!!!!

24

CAD-CAM in Knitting

Documents

Transcript of CAD-CAM in Knitting