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SEMINAR TOPICS-PROJECTS-PAPER PRESENTATIONS
AUTOMATIC COCONUT DESHELLER
ABSTRACT
Agriculture is the backbone of India. The agriculture field produces lot products such as rice, sugarcane, turmeric, cereals, coconut, etc. In that coconut is one of the most products. Coconut plays an important role in the economic, social and cultural activities of millions of people in our country. India is a major producer of coconut in the world. The coconut is one of the major sources for several agro-based industries. Wide ranges of products obtained from coconut are coconut oil, rope, buttons, chocolates, cookies and several other domestic uses. All parts of coconut tree is useful in one way or other and the crop profoundly influences the socio-economic security of millions of farm families. Now-a-days agricultural field faces the scarcity in workers. Due to shortage of labour, time consumption is more and wages for labours are high. The total production of coconut in 2007 was 515,000MT out of which 470,000MT are used by coconut oil industries. Coconut oil extraction involves dehusking the coconut, breaking it into two halves, deshelling the coconut and extracting the oil from the kernel. The most of the above processes are performed manually. Hence a innovative technique implemented to automate the removal of the kernel from the coconut shell, thereby reducing the manual labour.
INTRODUCTION
Coconut plays an important role in the economic, social and cultural activities of millions of people in our country. India is a major producer of coconut in the world. Coconut provides food, edible oil, industrial oil and health drink to humanity.
All parts of coconut tree is useful in one way or other and the crop profoundly influences the socio-economic security of millions of farm families. Coconut oil, which comes under edible-industrial group, is used as a cooking oil, hair oil, massage oil and industrial oil. Coconut oil can be blended with diesel, straight in an adapted engine or turned into biodiesel.
Amount of coconut oil exported to the world market during 2004 was 2.06 million tonnes (up from 1.10 million tonnes in 1980), of which the European market absorbed about 44.5 per cent and others such as US and Asia Pacific received 23.3 per cent and 24.7 per cent, respectively. India has unbeatable quality advantage in this sector. Refined coconut oil is mainly used in the manufacture of biscuits, chocolates and other confectionery items, ice cream, pharmaceutical products and costly paints.
Now a days the shell and kernell are removed manually using knife and hooks. Automation results in reduction of human effort and improves productivity of the industry by leaps and bounds. The ‘Automatic Coconut Desheller’ preheats the partially dry coconut (reducing drying time), deshell the kernel.
1.LITERATURE REVIEW
The coconut is one of the main sources of oil products. In order to obtain the oil from the coconut, there are number of process to be done. The processes are coconut plucking, dehusking, breaking shell, drying, deshelling the kernel from the shell and finally extracting the oil from the kernel. In the above process, the time consuming is the coconut deshelling, since it is done by using manual labours. Most of the regions use manual deshelling at present. The coconut is deshelled by means of using knifes, hooks, etc. Due to manual process, time is consumed, other major disadvantage is the labour problem and by using the external devices there may be a chance of accidents takes place. In order to avoid such kind of difficulties we go for the automation process.
By means of using the automation in coconut deshelling process the productivity is increased, labour problem is controlled, time is reduced and cost is also reduced for deshelling process. In this automatic coconut deshelling machine the dried coconut is automatically loaded in the gravity feed mechanism clamper setup and the kernel is removed from the shell by means of specially designed blade which is
attached to the double acting cylinder with stepper motor arrangement. Thus the shell and kernel are collected separately by using AUTOMATIC COCONUT DESHELLING machine.
2.1. PROBLEM DEFENITION:
At present the deshelling process is performed manually. Insufficient labour strength, skillful work requirement makes the process tedious and time consuming. There is a chance of accidents during manual process. The labour cost also collectively adds up to the cost of the product. The problems like time consumption and labour insufficiency can be overcome by automating the process.
2.2. SCHEMATIC DIAGRAM:
Fig 2.1 Schematic Diagram
2.3 BLOCK DIAGRAM:
Fig 2.2 Block Diagram
3. DESIGN OF THE PROJECT:
3.1 DESIGN PROCEDURE:
The design of our project consists of the following steps
1. Design of blade
2. Selection of cylinder and solenoid
3. Design of clamper
4. Selection of sensor
5. Selection of stepper motor
6. Programming Microcontroller
7. Design of Relay
8. Power supply circuit
9. Conveyor design
3.2 COMPONENTS USED:
The main components used in our project are
1. Pneumatic Supply
2. Double Acting Cylinder
3. Blade Setup
4. Clamping Setup
5. Conveyor Setup
6. Proximity Sensor
7. Stepper Motor
8. Microcontroller
9. Relay Circuit
10. Power Supply
3.2.1 PNEUMATIC SUPPLY:
COMPRESSOR:
SPECIFICATIONS OF THE COMPRESSOR:
Motor / 3 HPTank Capacity / 250 liters
Work pressure / 12 kg/cm2
Displacement / 310 lts/mm
RPM / 720 rpm
THREE PHASE INDUCTION MOTOR:
An electric motor is a device which converts an electrical energy in to mechanical energy. The working principle of three phase induction motor is based on the production of rotating magnetic field. The rotating magnetic field is produced by supplying current to a set of stationary windings with the help of three phase A.C supply. The rotor of three phase induction motor is coupled with shaft of the compressor.
FRL unit:
FRL stands for Filter, Regulator and Lubricator. The function of air filter is to remove all foreign matter and allow dry, clean air to flow without restriction to the regulator and then on to the lubricator. Filters are available in wide ranges starting from a fine mesh wire cloth(which only strains out heavier foreign particles)to elements made of synthetic materials (which are designed to remove very small particles)usually in-line filter elements can remove contaminants in the 5 to 50µm range.
The function of air pressure regulator is to regulate the pressure of the incoming air so as to achieve the desired air pressure at a steady condition. Thus the air pressure regulator act as a pressure guards by preventing pressure surges or drops from entering the air circuits.
The function of an air lubricator is to add a controlled amount of oil with the air to ensure proper lubrication of internal moving parts of pneumatic components. The lubricator ads the lubrication oil in the form of fine mist to reduce the friction and wear of the moving parts of pneumatic components such as valves, packing used in air cylinders, etc.
3.2.2 DOUBLE ACTING CYLINDER
A "double-acting" cylinder has two ports through which the supply of air is reversed to cause displacement in either direction. The general specification for a pneumatic cylinder is in terms of the bore diameter of the cylinder, the stroke length of the piston and the maximum operating pressure range.
To return the piston to its resting position, not only apply pressure to the second port, but also open up the first port so that the gas in it can be expelled. In this project double acting cylinders are used for the obtaining upward and downward movement of the blade setup.
Acting Cylinder Table 3.2 Specifications of Double
PARAMETER / VALUEMake / JANATICS
Stroke Length / 160mm
Bore Diameter / 40mm
Max Pressure / 20 bar
Fig 3.5 Schematic representation of Double acting cylinder
3.2.3 BLADE SETUP:
The blade with ‘S’ shaped hook is used for deshelling the coconut. The thickness of the blade is 1 cm. The blades are having the diameter of 7cm. The fixed blade is mounted to the rotor spindle of stepper motor at 90 degree angle for easiest removal of the kernel due to ‘twist and pierce’ action. The blade setup is fixed to the stepper motor, when the stepper motor provides the rotating motion it causes the rotating movement in the blade to seperate the coconut shell and kernel.
Fig 3.7 Front View of Blade Setup Fig 3.8 Top View of Blade Setup
The specifications of the blade used are,
Corrosive resistant steel
n Tensile strength = 630 N/mm²
n Yield strength = 480 N/mm²
n Brinell hardness number = 241
n Heat treatment
Heated to 1000°C, Air cooled and tempered at 600°C.
These are all the specifications of the blades used for harvesting the flowers.
Fig 3.9 Blade with proximity sensor
3.2.4 CLAMPING SETUP:
Clamping mechanism plays an important role in our project because the clamping and declamping need not involve any human assistance. Therefore considering above criteria it is decided to use ‘Gravity Feed Mechanism’ for the clamping purpose. As shown in figure clamping setup consists of two shells one of which is fixed and the other is movable one. A weight is attached to the movable shell of the clamper through a lever.
As the clamping setup is attached to the conveyor, it moves along with the conveyor. When the clamping setup is loaded with the dried coconut, due to the gravitational force acting over the weight the clamper holds the coconut shell tightly. After the deshelling process is over, the clamping setup reaches end of the conveyor and it becomes upside down so that the clamp releases the coconut shell, which falls into the collecting basket.
Fig 3.10 Front view of clamper Fig 3.11 Top view of clamper
Fig 3.12 Clamper with shell
3.2.5 CONVEYOR DESIGN:
CONVEYOR SETUP:
A belt conveyor consists of two or more pulleys, with a continuous loop of material - the conveyor belt - that rotates about them. One or both of the pulleys are powered, moving the belt and the material on the belt forward. The belt consists of one or more layers of material they can be made out of rubber. Many belts in general material handling have two layers. An under layer of material to provide linear strength and shape called a carcass and an over layer called the cover.
· Available in different widths and lengths to suit customer requirement. These may be flat belt type, toughed belt type and even cleated belt type. Belt conveyors are used in conveying powdered material or bulk material. They are also extensively used in packing lines, assembly lines, inspection lines. In certain applications metal detectors can be coupled to belt conveyors which facilitate online inspection and avoid any metal particle to remain in the material. These also find good application in conveying material to a long distance.
· Automation Systems has developed special belt conveyors wherein material can be transferred in 90o and even 180o.
BELT MATERIAL:
Cotton/nylon is one of the best quality synthetic fibers that the rubber industries use nowadays. The nylon canvas is woven by nylon fibers both in warp and in weft, it is most widely used fabric in rubber industry, and its outstanding merits are high abrasion resistance, high tensile strength and good fatigue resistance. Conveyor belts with nylon canvas inside have the characteristics of thin belt body, high tensile strength, good shock resistance, good trough ability, high adhesion between plies, splendid flexibility and long working life.
BELT CONVEYOR ADVANTAGE:
A belt conveyor has the advantages of simplicity of construction, high efficiency and low frictional loss resulting in low power requirements and economy in upkeep. It may be horizontal or inclined or a combination of both and can be arranged to convey material up or down an incline.
CLEANING & Protection of Belts:
Most materials handled in bulk by belt tend to cling to the belt after passing the discharge point and then fall off on the return run on meeting the return idlers. Dirt on the belt while passing over snub or tandem pulleys can seriously affect the belt.
Thorough cleaning of belt immediately after the discharge point and prior to return run should receive careful consideration.
CONVEYOR SETUP:
Fig 3.14 Belt conveyor with clamper
3.2.6 PROXIMITY SENSOR:
Inductive proximity sensors are widely used in various applications to detect metal devices. They can be used in various environments (industry, workshop, lift shaft...) whenever high reliability is required.
Inductive proximity sensors generate an electromagnetic field and detect the eddy current losses induced when the metal target enters the field. The field is generated by a coil, wrapped round a ferrite core, which is used by a transistorised circuit to produce oscillations.
The target, while entering the electromagnetic field produced by the coil, will decrease the oscillations due to eddy currents developed in the target. If the target approaches the sensor within the so-called "sensing range", the oscillations cannot be produced anymore: the detector circuit generates then an output signal which controls a relay or a switch.
3.2.7 STEPPER MOTOR:
A stepper motor is a brushless, synchronous electric motor that can divide a full rotation into a large number of steps, for example, 200 steps. Thus the motor can be turned to a precise angle.
Fundamentals of Operation:
Stepper motors operate much differently from normal DC motors, which simply spin when voltage is applied to their terminals. Stepper motors, on the other hand, effectively have multiple "toothed" electromagnets arranged around a central metal gear, as shown at right.
To make the motor shaft turn, first electromagnet is given power, which makes the gear's teeth magnetically attracted to the electromagnet's teeth. When the gear's teeth are thus aligned to the first electromagnet, they are slightly offset from the next electromagnet. So when next electromagnet is turned on and first is turned off, gear rotates slightly to align with next one. The process is repeated. Each of those slight rotations is called a "step." In that way, the motor can be turned a precise angle. There are two basic arrangements for the electromagnetic coils: bipolar and unipolar.
A stepper motor can be viewed as a DC motor with the number of poles (on both rotor and stator) increased, taking care that they have no common denominator. Additionally, soft magnetic material with many teeth on the rotor and stator cheaply multiplies the number of poles (reluctance motor). Like an AC synchronous motor, it is ideally driven by sinusoidal current, allowing a stepless operation, but this puts some burden on the controller. When using an 8-bit digital controller, 256 microsteps per step are possible. As a digital-to-analog converter produces unwanted ohmic heat in the controller, pulse-width modulation is used instead to regulate the mean current. Simpler models switch voltage only for doing a step, thus needing an extra current limiter: for every step, they switch a single cable to the motor.