The present paper is aimed to design and develop a process to extract high-quality natural fibers from the banana pseudo stems. Manual extraction of banana fiber produces good quality of fiber but it much time-consuming. Labour expense is quite high and output is quite low. Hence efficient extraction of banana fiber can only be possible through mechanization. The traditional extracting method cannot be applied for mass production of banana fiber. Banana fiber extracting machine is designed in a very simple way such that it can be used by everyone, as the mechanism is very simple. The major components used are blade, belt and pulley, motor, and roller shaft. This machine is helpful in fibre industries to extract the fibre from banana stem.
The major components involved in the design and the fabrication of the banana fiber extracting machine are as follows
Roller is the most important element in this machine. It applies necessary squeezing force on pseudo stem of banana separating the pulp, leaving only the fiber. Type of the roller used mainly affect the quality of fiber. When compared extraction fiber unit, the roller could separate a good texture of banana leaf sheath. While saw tooth bar type made damage to the texture. So in our model, we are going to use normal blade rollers. The clearance between the rollers is 5 to 8mm. The thickness of the pseudo stem is 10mm to 15mm.so, clearance is enough. There are two fixed rollers for feeding and another one is rotating roller in which the rotating roller is the maximum size roller.
1) Roller outer diameter is 140mm (with blades)
2) Roller inner diameter is 120mm
To keep the torque constant, inner diameter is 80% of the outer diameter.
This is made of mild steel and sheet metal material. The whole parts are mounted on this frame structure with a suitable arrangement. Boring of bearing sizes and open bores did in one sitting so as to align the bearings properly while assembling. Provisions are made to cover the bearings with grease.
An electric motor is a machine that converts electrical energy into mechanical energy. Its action is based on the principle that when a current-carrying conductor is placed in a magnetic field. It experiences a magnetic force whose direction is given by Fleming’s left-hand rule.
D. Ball Bearings
Ball bearings, as shown below, are probably the most common type of bearing. They are found in everything from inline skates to hard drives. These bearings can handle both radial and thrust loads and are usually found in applications where the load is relatively small. In a ball bearing, the load is transmitted from the outer race to the ball, and from the ball to the inner race. Since the ball is a sphere, it only contacts the inner and outer race at a very small point, which helps it spin very smoothly. But it also means that there is not very much contact area holding that load, so if the bearing is overloaded, the balls can deform or squish, ruining the bearing.
A fixed pulley has an axle mounted in bearings attached to a supporting structure. A fixed pulley changes the direction of the force on a rope or belt that moves along its circumference. Mechanical advantage is gained by combining a fixed pulley with a movable pulley or another fixed pulley of a different diameter. The material of the pulley is mild steel because during operation the pulley is out of the processing area. The processing area is covered by the fiber casing
Its working is a very simple and easy one. It consists of two fixed rollers for feeding and one rotating roller. Other than this, it consists of two pulleys, two bearings, one shaft, supports and cashing. It is a simple machine consisting of a single roller which rolls on a fixed support. 1hp motor is used to provide input power to machine. The machine reduces labor work and increases fiber production by 20-25 times as compared to a normal machine. The motor starts and rotates the driver pulley and power is transmitted to the driven pulley through the power transmission by the belt.
After, it rotates the roller. Now the sized stem is feed through the two rollers. The machine is constructed with an ac motor to rotate, attached with a rotating shaft and this is coupled with blades. When the banana stem is pushed into the fiber extractor with the help of two rotating shafts when the banana stem is inserted into the extractor the blade rotates with the help of a motor.it continuously rotates and shattered the banana stem and extracts fiber. After shattering banana stem in the working area by using the blade attached with motor shaft after the process finished then banana fiber is carried out in the extractor. The fiber is then used for industries.
Design calculation of machine:
The banana fiber extraction machine can be designed with higher efficiency. This machine will reduce manual work and is suitable for mass production. Compact structure and easy disassembling will be another advantage. The problem of impurities and knots can be solved with this kind of design. The factors affecting the quality of fiber are roller speed, feed angle and clearance also affect the production quantity of fiber. By choosing these factors correctly, the quality and production of fiber can be increased. The project carried out by us made an impressing task in fiber industries. It is very usefully for the workers. This project has also reduced the cost involved in the concern.
Source: slideshare.net, researchgate.net