How does winding occur in roving frame:
The thin and light fiber wave roving continues to emerge from the front roller surface of the frame. This delivered wave is converted into a specific package with a slight twist, which is easily used in subsequent machines. In a roving frame, the spindle and bobbin both rotate in the same direction at different speeds. The difference in speed between the two surfaces helps to slowly wind the roving on the surface of the roving bobbin. Two methods are generally used to attach the roving to the surface of the bobbin. https://bdfabric.com/system-of-imparting-twist-in-roving/
Sometimes the roving wraps around the surface of the roving bobbin by increasing the speed of the flyer or spindle while keeping the bobbin speed constant. Again, keeping the speed of the flyer or spindle constant, the speed of the bobbin is slowly reduced from the fixed speed, and the roving is attached to the surface of the roving bobbin. Thus the bobbins are winding in the roving frame.
Definition of winding:
Winding is the method of twisting the thin and light fiber wave delivered from the surface of its front roller in the roving frame to the surface of the roving bobbin at a certain speed by holding the points by giving a slight twist. Since the roving bobbin is made by twisting the roving, it is called winding the roving bobbin. This is usually done by differentiating the roving frame spindle and the roving bobbin.
Discussion of winding principle in roving frame:
The delivery portion of the roving frame consists of two parts—the bobbin and the flyer. Both the bobbin and the flyer rotate very fast while the machine is running. As a result, the roving begins to get tangled in the bobbin. But when both the flyer and the bobbin are rotating, there is some difference in the speed of the two, so the roving can get tangled in the bobbin. Bobbin surface motion and spindle speed are both important aspects of the winding principle.
How does winding occur in roving frame. Apart from this, the amount of winding should be fixed depending on the length of roving delivered from the front roller. So there needs to be a combination of bobbin speed and flyer speed with the length of roving being delivered. Otherwise, the delivered roving will be wasted, no winding or excess winding will tear the roving due to tension and increase wastage, not proper winding.
Therefore, a policy or strategy has been devised for winding the roving bobbin with the aim of eliminating the above defects or problems. This strategy works in two ways:
1. Flyer leading.
2. Bobbin leading.
1. Flyer leading:
In the flyer leading method, the speed of the flyer is always higher than the speed of the bobbin and the diameter of the bobbin gradually increases due to the attachment of roving to the surface of the bobbin. As a result, the speed of the flyer increases slowly to keep the winding speed constant. The method in which the roving is attached to the surface of the bobbin is called Flyer leading winding. Such machines are generally used for jute, wool, etc. The machine which has flyer leading is called a flyer lead machine.
2. Bobbin leading:
In the bobbin leading method, the bobbin speed is always higher than the flyer speed, and the diameter of the bobbin increases due to the roving being attached to the bobbin surface. As a result, the speed of the bobbin has to be slowly reduced to keep the winding fixed. The method by which this winding is done is called bobbin leading winding. A machine that has bobbin leading is called a bobbin lead machine.