Circular Jacquard Knitting Machine

The slide is about Knitting, Jacquard Knitting, Objective of Jacquard Knitting, Classification of Jacquard Knitting. The slide contains Semi Automatic Jacquard Knitting components, formation of Knit, Tuck and Miss loop, Electrical Jacquard Knitting Machine Principle, Components, Electronic needle selection. Formation of loops, Multi-step Geometric Needle Selection and Pattern Wheels

1. Circular Jacquard Knitting Machine Submitted By: Avishek Das Gupta ID: 201818004 Subject: Fabric Manufacturing Machinery & Maintenance Department: TMDM Level 4 Term 1 Submitted To: Prof. Dr. Shaikh Md. Mominul Alam Head, Department of TMDM

2. Knitting: Knitting is the second most popular technique of fabric or garment formation by inter-looping one or one set of yarns. Knitting is the technique of fabric formation by inter-looping. The straight continuous length of yarn is bent into loops and those loops are interloped for fabric formation. The main element responsible for such loop formation and subsequent inter-looping is the needle. Jacquard Knitting: Jacquard is a term originally from weaving. In a simple explanation it is the process of combining 2 or more colors together by knitting one color either to the front or to the back of the fabric so as to create a visual pattern. So, the jacquard knitting machine has a different principle & working method.

3. Objective of Jacquard Knitting: In jacquard fabric different types of motif is made. For making a motif in fabric, required more number of different wales in a repeat. For more number of wales need of needle more cam track. For more number of cam need higher length needle. But if the needle length is increased, the strength of needle will be decreased. So, the needle will be damaged during production. So, the normal "Knitting mechanism is not used in jacquard knitting machine. Selector mechanism is used in jacquard machine.

4. Classification of Jacquard Knitting Circular jacquard knitting machine can be classified in two types : Mechanical jacquard Electrical jacquard Classification based on needle selection : (Covered in this presentation) Semi Automatic Jacquard Knitting Electromagnetic Needle Selector Multi-step geometric needle selection Pattern wheels

5. Semi Automatic Jacquard Knitting Components: Main cylinder Needle Intermediate Jack Selector Jack Adjustable Stitch Cam Fixed Raising Cam Cam box Peg Box Pattern Jack

6. Main Components: Jack Cam, Needle Cam, Pin Cam, Sinker Cam Jack

7. Main Components: Needle P in Sinker

8. Cam Box: 2 tracks are present in one cam box Upper track for needle butt. Lower track fore Intermediate jack butt There are 2 types height are present in lower track: Lower Height for making Tuck loop Upper Height for making Knit loop There are no any system in upper track to rise the needle, but for lower, track has a system to rise the intermediate jack. So, upward movement of needle depends on movement at Intermediate jack. If the Intermediate jack is risen, the needle will be automatically risen, because the needle and intermediate jack one composed with one another. Again, There are no any system in lower track to down the Intermediate jack, but for upper track has to down the needle has a system to down the needle.

9. Formation of loops: When The Machine Movement is Clockwise

10. Formation of loops: Knit loop, Tuck loop and Miss loops are formed according to slots conditions Knit loop: If both slots are empty (No selector pin in slot) the needle will not face any problem to rise its highest position. So knit loop is produced. Tuck loop: If right slot is filled by selector pin/pattern jack, when the needle moves clock wise (Left side to right side)then the needle will be disturbed to rise its highest or cleaning position. So the tuck loop is created. Miss loop: If left slot is filled by pattern jack, the needle at starting will be faced problem to rise. So, the miss loop is created.

11. Formation of loops: Needle Needle Butt Engaged with one another Intermediate Jack Butt for A and B Selector Jack Main Butt Cam Box Slot Cartridge

12. Formation of loops:

13. Formation of loops: Knit Loop Tuck Loop Miss Loop Intermediate Jack Risen by cam Down by Needle Incomplete Risen by cam Disengaged Disengaged Needle Risen by Intermediate Jack Down by cam Incomplete Risen by Intermediate Jack Will not reach to the clearing position Will not Rise

14. Formation of loops:

15. Electromagnetic Needle Selector Electrical Jacquard Knitting Machine : A jacquard circular knitting machine is disclosed provided with a needle cylinder driving mechanism capable of optionally and readily controlling the rotary motion of the needle cylinder according to the pattern to be knitted. A motor interlocked through gears or the like with the needle cylinder rotates according to a needle cylinder rotating procedure stored previously in a magnetic memory medium. Needle actuators operate according to a pattern forming procedure stored in another magnetic memory medium as a signal is provided by a sensor for sensor for detecting the rotary motion of the needle cylinder. Thus a jacquard circular-knitted fabric having predetermined patterns can be knitted efficiently .

16. Components: 1. Electromagnetic Needle Selector (ENS) – (It is a permanent magnet surrounded with coil) 2. Jack Cam Box and Jack cam 3. Spring Jack. 4. Special Cam Box For Electrical Circular Jacquard 5. Needle 6. Sinker ENS

17. Main Components: Electromagnetic Needle Selector Spring Jack Jack Cam Box Needle

18. Formation of loops: ENS (Electromagnetic needle selectors) Sinker Special cam box for electrical circular jacquard

19. Electronic needle selection

20. Working Principle Needle position (when magnet neutralized) A magnet or selector is placed under the needle and front of the control spring. The needle stands on head of the jack and the needle doesn’t have any raising cam. When no electricity passes through the magnet it becomes neutralized. So ENS can not hold control spring. The control spring pushes the jack and butt detached from the raising cam. The needle keeps it position in the down.

21. Working Principle Needle position (when magnet excited) Again when the magnet becomes excited (electricity flow), ENS holds down the spring. The spring also holds the jack in position. Jack butt remains in the jack cam track and it follows the raising cam. So the needle lifts up.

22. Formation of loops Knit Loop Formation: To form knit loop, every jack cam box contains two raising cam side by side. The left raising cam leads a needle to the clearing position with help of the needle cam because both raising jack cam are came height of the yarn taking height. For the both raising cam there are two ENS one for each. The spring jack constructed in the way that there is no interruption its butt always follows the raising cam. So when the magnet becomes excited (electricity passes) the raising cam push the jack and jack push the needle so form the knit loop. Again when the magnet becomes neutral the Jack butt remains in the jack cam track and it follows the raising cam. So the needle lifts up.

23. Formation of loops Tuck Loop Formation: To form a tuck loop no electricity passes through the first ENS so it remains magnet and attract the jack and jack become detached from the raising cam and the needle keeps it position in the down. So no clearing action is happened. But when electricity passes through the second ENS which makes the second ENS neutral and jack moves upward following the raising cam and so needle also move upward. In here needles raises only to the yarn taking height not in the clearing position so the old loop tucked in the latch and take the new yarn. Following the next knit loop a tuck loop is formed.

24. Formation of loops Miss Loop Formation: When miss loop is required no electricity passes through neither ENS nor the ENS keeps the jack detached from the raising cam whole the time. The needle remains in the bottom most position. So neither clearing nor the yarn taking takes place. In this way miss loop is happened.

25. Multi-step Geometric Needle Selection Multi-step geometric selection has been developed from the Brinton trick wheel of 1926, which first employed single butted depressible selectors beneath the cylinder needles rather than in an intermediate drum. Figure illustrates a device, used on Wildt Mellor Bromley machines of the RTR range, for either rib jacquard or rib loop transfer selection on circular garment-length machines with revolving cam systems. Each vertical column around the drum has a height of either 24 or 36 selection positions, depending upon the model. This depth corresponds to the pattern width repeat. The drums are either drilled with holes to receive push-in metal pegs or are equipped with grooved tricks for the insertion of pattern jacks whose butts are snipped off according to the pattern. The latter arrangement is generally preferred as the jacks can be prepared in a less laborious operation whilst the machine is knitting another design.

26. Multi-step geometric needle selection Vertically – Cylinder needle Horizontally – Dial needle Black portion – spring loaded lifting jack, which has 3 butts [ A (upper edge), G(raising butt) & Y ] E – Brinton Trick Wheel Z – Needle Butt F – Raising Cam B – Selector Presser X – Pattern Butt D – Pattern Bit C – Spring-loaded Plate

27. Working Principle The tail of each cylinder needle is supported by the upper edge (A) of a spring tailed lifting jack. A selector presser (B) is placed in front of each jack in a trick. The presser has a complement of 24 or 36 pattern butts corresponding to the width repeat; all except one butt (X) are removed so that a chevron or echelon pattern butt set-out is arranged around the needle cylinder. The tail of the lifting jack is sprung outwards, so that its raising butt (G) is in the line with the raising cam (F). [F may be either a clearing cam or a rib loop transfer cam.] If raising butt (G) follows the profile of cam (F), the jack will lift its cylinder needle to either knit or transfer its loop, depending on the cam position and shape.

28. Working Principle The selection is indirect, requiring a decision for non-movement of the needle. When a pattern bit (D) is placed in the vertical row of the drum directly facing the cylinder at the same height as the pattern butt (X) of a needle jack presser, the spring-loaded plate (C)at the height will be pivoted towards the cylinder so that it presses against butt (X) as it passes by. This causes the tail of the jack to be depressed into cylinder so that its butt (G) goes behind the raising cam (F) and the needle is not lifted. (creates a miss loop) Needle butt (Z) is used to lower the needle and this, in turn, lowers the jack ready for the selection at the next cam system. The effect of the selection may be cancelled (for example, in the rib border of a garment length) by introducing a raising cam to lift all jacks by means of butts (Y).

29. Pattern Wheels The pattern wheel is a cheap, simple device occupying little space, and is unique in employing separate raising cams, in the form of pattern bits, to select and move individual elements, to three different positions in their tricks. It is most popular in single-jersey machines, either as an inclined wheel for needle or point selection, or as a horizontal wheel for plush sinker selection. The wheels, tricked to the same gauge as the revolving cylinder needles, are driven continuously in the opposite direction, either by the needle butts or by gearing from the cylinder.

30. Working Principle

31. Working Principle The wheels are of the gain or loss type so they do not produce an exact number of complete turns in one machine revolution. The inclined pattern wheel is normally placed at each feeder. It is set at an angle of 20–40 degrees in place of the solid raising cam so that, as it turns, it lifts any element whose butt rests on a pattern bit. With a three-position wheel (Fig. 11.9), a needle entering an empty trick will remain at miss height (3), a needle supported by a low bit will be lifted to tuck (2), and a needle supported by a high bit will be lifted to clear (1).

32. Working Principle Needles left at miss height are lowered by a wing cam (X). Another mechanism often used which is a moveable raising cam, usually acting onto a butt at a level lower than the pattern wheel. When the cam is raised into action, it causes all needles to be lifted to knit and thus cancels the selection for a number of courses so that alternating bands of design and plain single colour may be produced. Alternative methods of needle selection with higher productivity, less restrictive pattern areas, and quicker pattern-changing facilities have replaced the pattern wheel as the most popular method of pattern selection

33. THANK YOU REFERENCE Book; KNITTING TECHNOLOGY, David J Spencer https://www.youtube.com/watch?v=8sqCQTw3U-M https://www.academia.edu/21736478/Thesis_on_Circular_Jacquard_knitting_machine