Feed mechanism of sewing Machine

Feed system plays a vital role for fabric feeding and it's movement
Apparel Engineering II describes different types of feed system in garment industry.

1. Presented By Md. Shamsuzzaman B.Sc. (WUB), M.Sc. (BUTEX) Lecturer, Department of Textile Engineering World University of Bangladesh Contact: [phone] Email: [email protected] WORLD UNIVERSITY OF BANGLADESH Department of Textile Engineering 7/13/2020 Slide Prepared by- Md. Shamsuzzaman Feed Mechanism Course Name: Apparel Engineering II Course Code: TE 703

2. Overview of the Class Definition of feed mechanism Functions of feed mechanism Functions of teeth in feed dog 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 2

3. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 3 Definition of Feed mechanisms T he process by which the fabric is moved forward in the feeding zone of the sewing machine I t refers to how the needles, bobbins, loopers , auxiliary feed mechanism parts, and the fabric being sewn itself moves T he only way for the needle to be able to engage the next portion of the material being stitched Industrial machine may have single option/combined option

4. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 4 Functions of Feed Mechanisms To advance the fabric in the feeding zone of the sewing machine Proper   seam appearance , Proper stitching as required Controlling of SPI ( Stitch per inch), Sometimes crease effect is formed according to the design Operation & to avoid different sewing faults Appropriate feed mechanism is sleeted to confirm case in sewing

5. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 5 Different Parts of Sewing Machine Feed Mechanism The following are the three parts of a sewing machine feed mechanism Throat plate or needle plate Feed dog Pressure foot

6. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 6 Types of Feed Mechanism Drop feed mechanism Differential bottom feed mechanism Adjustable top feed mechanism Needle feed mechanism Unisom feed mechanism Puller feed m mechanism

7. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 7 Drop feed mechanism The simplest feed system of sewing of sewing machine still commonest While starting the machine feed dog start from position 1 by holding the lower part and moves towards the back of the machine and drops fabric at position 2 Then slow down and comeback oppositely (from 3 to 4) Again holds the fabric ply and starts the second cycle Most of the domestic and industrial purpose it is suitable Distinction of the speed of lower fabric ply and upper fabric ply may cause sewing faults

8. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 8 Differential bottom feed mechanism Modification of drop feed system and follow the same principle The differential feed system contains two feed dog; one in front of the needle and another behind the needle The speed of individual feed dog can be controlled When the speed of the front feed dog is higher than back, the fabric will store in the position of both feed dog and will create pleat like effects during sewing Extensively used for stretchy materials When the speed of the back feed dog is higher than front, the fabric will achieve stretching and gathering effect

9. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 9 Adjustable top feed mechanism In this system, the presser foot works in two section One presser foot hold the fabric and another moves the ply backward after sewing. Both drop feed & differential bottom feed mechanism can used here Combination of adjustable feed & differential bottom feed can make top ply gathering or the gathering of bottom ply

10. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 10 Needle feed mechanism Then needle rise up & moves to form the next stitch with one step advance For the change of stitch length, setting of bath needle & feed dog should be changed . Practically useful in bulky sewing situation such as when quilting through the fabric. wadding & for slapping fabrics Another name of needle feed mechanism is “Compound feed” Needle itself moves forwards & backward Needle penetrates the fabric enters into the note of the feed dog & for the advance movement of 1 stitch length of fabric feed dog & needle pass the same distance at the same time

11. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 11 Unisom feed mechanism The inside presser foot & needle are driven at the same time toward the same direction No possibility of ply shifting Suitable for sewing stitch fabric & for bulk seam in heavy weight materials Normally used in special case The presser foot has two independently driven section; the holding & the feeding feet This system is made by combination of needle feed & positive top & bottom feed In this system one presser foot is inside the other presser foot & gives movement at different times

12. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 12 Puller feed mechanism Useful in multi needle machine specially for W/B making. Modification of drop feed system where A pair of roller used These rollers give a pulling motion on the fabric behind the presser foot Top roller is generally driven by machine whitest the lower one moves due to control & presser of the top roller The surface speed of puller roller is slightly higher then the feed dog speed to presser ply shifting roping

13. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 13 Types of feed dog teeth Fine-toothed feed dogs with a pitch of only 1.0–1.25 mm can be used to prevent this For sewing of light to medium weight fabrics, a tooth pitch (distance from peak to peak) of 1.3–1.6 mm is normal, with the peaks slightly rounded off if damage occurs on fine fabrics. On heavyweight fabrics, a certain amount of sagging is required for satisfactory feeding in order to keep both plies together. In this case, coarser feed dogs of 2.5 mm tooth pitch may be needed.

14. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 14

15. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 15 Further Study https://clothingindustry.blogspot.com/2018/03/feed-mechanism-sewing-machine.html#:~:text=The%20three%20main%20kinds%20of,the%20needle%20back%20and%20forth. https://textilelearner.blogspot.com/2013/07/different-sewing-machine-feed-mechanism.html https://www.youtube.com/watch?v=avr3pN_udMA

16. 7/13/2020 Slide Prepared by- Md. Shamsuzzaman 16 THE END