Experiment Name: Study on straight knife cutting machine.


Theory:
It is the most useful cutting instrument in apparel cutting. In apparel industry, more than 99% cases this knife is used. This machine is called straight knife cutting machine because its cutter is straight in shape. It is used for both woven & knit fabric. In this machine different types of straight knife are used according to the different cutting objects. This machine provides good efficiency.


Objective of the experiment:
1) To Learn about different parts straight knife cutting machine.
2) To learn about working principles of straight knife cutting machine.


Apparatus:
1) Straight knife cutting machine.
2) Cutting Table.
3) Fabric.


Machine Specification:
Brand : YAMATA
Model : FY - 103
Origin: Chine
Motor R.P.M : 3000

Name of the machine parts:
  1. Base Plate.
  2. Four Wheel
  3. Pressure foot.
  4. Motor Stand
  5. Sharp Mechanical Base
  6. Sharp Belt
  7. Three pinion shaft
  8. Leaver
  9. Sharp on leaver
  10. Operating handle
  11. Power cable carry handle
  12. Motor
  13. Oil Can
  14. On/Off Switch



Figure:





M/C description:
      a)     A base plate :Usually in rollers for easy movement.
      b)    An electric motor: Transmit motion to blade.
      c)     Handle: For the cutter to direct the blade.
      d)    Knife: It cut the fabric
      e)     Knife guard: It used as safety device to prevent any accident
      f)      Grinding wheel: Used to sharp the knife during cutting.
      g)     Stand: The backbone of the machine
      h)    Roller wheel: To move the machine over cutting table easily.

Working principle: Two kind of power are required to operate a straight knife.
        Motor power drives the reciprocating blade.
        Operator power drives the knife through the lay.

The motor power needed is determined by
        Height of the lay.
        The construction of the fabric.
        The curvature of the line being cut.
        The stroke of the blade.

The greater the power of the motor the heavier will be the machine. The taller stand, the thicker its cross-section and the greater its width, adding resistance to the forward movement on a curve. The greater the blade movement the faster the blade cuts the fabric and the more rapidly and easily the operator can push the machine. Operator effort is affected by the weight of the motor, the shape of the stand, handle height, stroke, sharpness of blade and the effect of the base plate rollers on the table surface.


Precaution to avoid blade deflection:
      1.     Reducing lay height.
      2.     The weight of the motor should be light.
      3.     The operator should be skilled and conscious.


Conclusion : >>>>>>>>>>>>>>>>>>>>>>