6 th sem project report

MANUALLY AND POWER OPERATED REAPER MACHINE
GUJARAT TECHNOLOGICAL UNIVERSITY, AHEMEDABAD, 2016 Page 1
Chapter: - 1
INTRODUCTION
1.1 Introduction :
Mechanized agriculture is the process of using agricultural machinery to mechanize
the work of agriculture, greatly increasing farm worker productivity. In modern times,
powered machinery has replaced many jobs formerly carried out by manual labour or by
working animals such as oxen, horses and mules. The history of agriculture contains
many examples of tool use, such as the plough. Mechanization involves the use of an
intermediate device between the power source and the work.
This intermediate device usually transforms motion, such as rotary to linear, or
provides some sort of mechanical advantage, such as speed increase or decrease or
leverage. Current mechanized agriculture includes the use of tractors, trucks, combine
harvesters, airplanes (crop dusters), helicopters, and other vehicles. Modern farms even
sometimes use computers in conjunction with satellite imagery and GPS guidance to
increase yields.
Rice is one of the most important crop and staple food of millions of people which is
grown in many countries of the world. The total area planted under rice crop in India is
42.20 million hectares.
Improved weeper reduces weeding cost by 79-90%. Walking type vertical conveyer
reaper, power tiller and tractor front mounted reaper save 50-60% labour and harvesting
cost by 60-70% as compared to manual harvesting. Combine harvesting save 40-50%
cost as compared to manual harvesting and threshing by power thresher. Use of pedal
operated thresher, motorized hold on thresher reduce time, labour, cost of threshing to a
great extent.
Reapers are used for harvesting of crops mostly at ground level. Reapers are
classified on the basis of conveying of crops. It avoids fuel consumption, labour
requirement. As the population of India increases day by day, there is increment of food,
vegetables so need of farm mechanization also increases, machineries provides more
operations in less time, but the machineries are very costly for the common man, it is not
affordable for them ,so manually and power operated machineries, equipment’s are also
the most important factor.
Reaper harvesters on the other hand are other alternative harvesting equipment,
provided straw is considered as economic by-product for animal feed and/or industrial
applications. Keeping these in view, a feasibility study was undertaken to reduce the cost
of harvesting in paddy crop through mechanization of harvesting and manually and power
operated reaper is more important for it, this type of reaper can easily be operated by
single person, only the pushing efforts are required in less economy, easily affordable for
farmers for keeping the better farming.

Mechanization refers to interjection of machinery between men and materials
handled by them. In agriculture materials are soil, water, environment, seed, fertilizer,
pesticides, growth regulators, irrigation, agricultural produce and by-products such as food
grains, oilseeds, fruits and vegetables, cotton, sugarcane, jute & kenaf and other cash
crops, milk, meat, eggs and fish etc. There is scope of mechanization in every unit
operation of production agriculture, post-harvest and agro-processing, and rural living.
Mechanization has varied connotations. While in the developed world it tends to be
synonymous to automation but in developing countries, like India, mechanization means
any improved tool, implement, machinery or structure that assists in enhancement of
workers’ output, multiplies the human effort, supplements or substitutes human labour that
is enabling and removing, avoids drudgery or stresses that adversely affect human mental
faculties leading to errors, imprecision and hazards and eventually loss of efficiency. It
also means automation and controls that assure quality, hygiene. Agricultural
mechanization in a limited sense relates to production agriculture.
Wheat is preferred food amongst all the cereals in the world. Concerted efforts are
needed to enhance food grain production in the world and to investigate problems that
stand in the way of meeting food needs of humanity so as to avoid peace upsetting and
famine occurrence in the world.
Wheat is the leading food grain of Pakistan, and being the staple diet of the people,
it occupies a central position on agricultural policies. It is the largest grown crop over an
area of 8666 thousand hectares in 2011-12, showing a decrease of 2.6 percent over last
year’s area of 8901 thousand hectares.
Wheat contributes 12.5 percent to the value added in agriculture and 2.6 percent to
GDP (Anonymous 2011-12). Despite the introduction of improved varieties of wheat,
better chemical and hydrological inputs, the production is still not enough to feed the
present population. Pakistan’s present problem is the augmentation of food supplies to
masses in order to meet the country’s needs. It could be accomplished either by bringing
more area under wheat cultivation or by increasing yield per unit area. Acreage increase
has limitations like scarcity of water and precariously established balance in land
allocation between equally important cash crops.
Any disturbance in this balance may cause another crisis, more or less of equal
severity. Hence, productivity enhancement along with pre and post harvest losses
management are the only alternative because of the existing differences between the
national average and the potential.
The wheat grain losses are classified as i) pre-harvest grain loss due to the birds,
rodents and environmental; ii) harvest grain loss during harvesting of the crop; and iii)
postharvest grain loss due to bundling, transporting, threshing and winnowing.

1.2 Problem Statement :
The intricate steps involved in planting, cultivating, harvesting, and preparing rice
requires an immense labor force. However, recently farmers have seen a shortage of
skilled labour available for agriculture. Due to high literacy rate and an urbanized life style,
a majority of the younger generation villagers have migrated to urban & other countries in
search of better jobs. The laborious nature of work, low-wage structure, low self-esteem
and lack of social status are some of the other reasons that lead to occupational mobility
of the paddy field laborers to other lucrative fields. Because of this shortage the farmers
have transitioned to using combine harvesters.
These harvesters are available for purchase but because of their high costs, they
are not affordable. However, agriculture groups make these available for rent on an hourly
basis. But the small holding farm owners generally do not require the full featured combine
harvesters. Also, these combine harvesters are not available in all parts of rural area due
to financial or transportation reasons. Thus, there is a need for a smaller and efficient
combine harvester which would be more accessible and also considerably cheaper.
1.3 Target Market:
Our target market includes both male and female small rice paddy cultivators with
land holdings of one or less acres, to about ten acres, in the states of India. Our manual
and power operated reaper would be available for both purchasing and renting.
For purchase
 Areas with no access to renting full featured harvesters and where manual labor is
not easily available.
For renting
 Small farms that do not need the complete harvest their crops. These would rent
our product on per hour basis.

1.4 Review of Literature:
This chapter deals with research work done in past by various investigation on the
performance,
Hadidi et.al (1984) stated that, the height of crop stubbles increasing as stalks
moisture content increased and decreased with increasing of knife velocity. He added that
the percentage of wheat and rice grain losses increasing as the machine forward speed
increased. Increasing cutter bar speed leads to decrease the percentage of grain losses.
Also, increasing forward speed leads to increase the number of uncut stalks.
Sahar (1988), reported that, the use of a large scale machine is inappropriate for
the following reasons:- it needs high technical experience for operation and maintenance,
high capital requirements. Low field efficiency is in small holding and losses of straw are
high on irregular furrowed soils. The use of small machines is appropriate for small
holdings, low capital requirements and low technical operations and maintenance
experience.
El-Sahrigi et.al. (1992) developed a front mounted repear. The design features
included a flat belt mechanism conveying the crop to the side of machine, improve cutter
bar star wheel assembly to minimize clogging, a bevel gear drive for power transmission,
a robust frame, a header provide design that will not dig in to the soil and provision to
covert the flat belt conveyor drivers to chain without frame modification.
Habib et.al (2002) stated that the parameters affecting cutting process are related
to the cutting tool, machine specifications and plant materials properties. They added that,
the cutting energy consumed in harvesting process.
Badr (2005) compared the performance of three different combines in terms of
harvesting time, grain losses, fuel consumption, energy required and total cost. He found
that the highest field capacity of 3.02 acre/h and the lowest field efficiency of 70.5 % were
obtained at forward speed about 4.0 km/h and grain moisture content of 22 %. D. N.
Sharma and S. Mukesh, they studied on the designing of handle and in that study
approximate 100 cm height is sufficient for pushing of any machinery. Er. Prabhakar Dutt,
Principal Scientist, studied star wheel, crop divider and conveyor design of reaper. Er.
Beds Prasad A., Er. Dalvi Devdatta N., Er. Virkar Amol D. (2013) developed manually
operated reaper and evaluated performance as well as its uses and drawbacks.

1.5 Present Design of Power Reaper:
4GL-120A power reaper was described to save time constraints and reduce the
cost of harvesting operation of rice by mechanization. This reaper was studied to
recommend the appropriate system for rice harvesting. The system was evaluated
according to the technical parameters: knife speed, operating speed, actual field capacity,
and theoretical field capacity, field efficiency, cutting efficiency, cost economics and
percentage of grain losses. The actual cutting width of the reaper was 1.2 m. In this study,
performance of power reaper used for rice harvesting was assessed and compared with
manual harvesting using sickle. The results showed that the actual field capacity of the
reaper was 0.24 ha/h compared to 0.05 ha/h for manual harvesting. Labor requirements
for reaper and manual harvesting were 4 and 28 man/ha, respectively. The fuel
consumption, knife speed, field efficiency and cutting efficiency were 1.89 l/h, 1.223 m/s,
92% and 98% respectively. The cutting cost of power reaper was 67% less as compared
with manual harvesting. The grain loss was less than 0.5% and was admissible. The
overall performance of power reaper for rice harvesting was found satisfactory.
Figure No.1 Present Design of Reaper

Chapter: - 2
Construction and working of reaper machine parts
Figure No. 2 Construction and working parts
 Frame:-The frame is use for supporting the part member use in this project.
Frame’s specification is in above the table.
 Ground Wheel:- Ground wheel is use for the travelling like one field to another
field. Specification of ground wheel is in above the table.
 Bearing: - A bearing is a machine element that constrains relative motion to only
the desired motion, and reduces friction between moving parts.
 Pulley: - A pulley is a wheel on an axle or shaft that is design to support
movement and change of direction of a taught cable, rope or belt along its
circumference.
 Sprocket: - A wheel that has row teeth around their edges which fit into the holes
of something and cause it to turn when the wheel turns also any one of the teeth on
such a wheel.

 Belt: - A belt is a looped strip of flexible material used to mechanically link two or
more rotating shafts. A belt drive offers smooth transmission of power between
shafts at a considerable distance.
 Chain: - Chain drive is way of transmitting mechanical power from one place to
another. It is often use to convey power to the wheels of a vehicle, particularly
bicycles and motorcycles. It is also used in a wide variety of machines besides
vehicle.
 Cutter Bar: - Made up of the knife sections and hold-down clips. The cutter bar
is positioned along the front part of the reaper. It will cut the crop by shearing
action.

Chapter: - 3
Reaper Selection
Reaper is generally selected on the land holding of the farmer, greater the land
holding, tractor operated vertical conveyer reaper is choose, for medium land holding
power tiller mounted vertical conveyer reapers are preferred. When we started with the
project manually operated reaper, we came across some problems. Due to those
problems the machine was not working properly. The design of the machine was
technically perfect, but due to some fabrication, material used and conveying mechanism
problem, it was not giving satisfactory results. We observed and came to the conclusion
that there are major problem of clogging and power requirement. We solved the problem
and got satisfactory result. We hope harvesting practices made easy by our some
developments provide in this machine. There are some different parameters which decide
the selection and performance of reaper, they are as follows;
i. Should have the proper cutting speed of cutter bar.
ii. Should require proper crop spacing.
iii. Should require proper power.
iv. Continuous power transmission.
v. Proper registration and alignment of cutter bar.
vi. Should require less effort.
Objectives
1. To modify the manually and power operated Reaper.
2. To evaluate the performance of modified manually and power operated Reaper.

Chapter: - 4
Sr.
No.
Description Dist-
ance
Time Qty Remarks
1 Material lifted to shop . 5 labour
2 Welding of frame . 1 labour
3 Inspection of welding frame .
4 A wait for the next operation .
5 Sprockets mount on the shafts .
6 Bearing mount on frame and
shaft fitted on the shaft
.
7 Inspection of all .
8 Ground wheel fitted on the
shaft
.
9 Inspection of ground wheel . 1 labour
10 Connect chain on sprocket 1 to
2 and 3 to 4
. 1 labour
11 Motor fitted on the shaft . 3 labour
12 Inspection of motor joint on the
frame completely fitted or not
.
13 Motor pulley connected with
second shaft
.
14 Disc connected on third shaft . 1 labour
15 Disc connected to connecting
rod
.
16 Connecting rod connecting
with iron strip
. 1 labour
17 Strip connected to cutter . 1 labour
18 Inspection of disc, connecting
rod and iron strip joint
.
19 Cross belt drive mounted on
vertical shaft
.
20 Strip connected to frame in
front side star wheel & crop
divider mount on
. 2 labour
21 One strip mount on frame just
front of second shaft and iron
wheel. Join the use of bolt
.
22 The handle joint on the frame
at besides with the use of nut &
bolt
.
23 Inspection of reaper machine .
24 Reaper machine store in store
room
. 2 labour
Total 15 6 1 1 1
Flow process chart of manually and power operated reaper machine

Chapter: - 5
Manually and Power Operated Reaper
5.1 Working Principle:
When machine is push by the operator at the designed speed in the field, rear
wheel rotation leads to reciprocate cutter bar with the help of sprocket and chain. The crop
lifter guides the crop to the cutter bar and the crop is cut by the cutter. The cut crop is
conveyed with the help of star wheel at one side by the lugged belt conveyer for easy
collection and bundling.
5.2 Parts used in manually and Power Operated Reaper:
Sr. No. Component Material Used
1 Frame Mild Steel
2 Ground Wheel Mild Steel
3 Rotating Disk Mild Steel
4
Shafts :
1.Ground wheel shaft
2.Idle shaft (v-belt pulley)
3.Rotating disc shaft
4.Rotating pulley shafts
High Carbon Steel
5 Crop Divider G. I. Sheet
6 Star Wheel Wood
7 Cutter Bar High carbon steel
8 Handles Mild Steel
9 Chain High carbon steel
10 Belt Rubber
11 Shaft Pulley Cast iron & Alluminium
12 Sprockets Gun metal & Mild steel
Table No. 1 Part Used

5.3 Specifications of Each Part:
5.3.1 Specifications of Frame:
1 Number of Square Pipes 4
2 Number of Bearing 8 (Dia. 20)
3 Length 1200mm
4 Width 550mm
5 Height 50mm
Table No. 2 Specification of Frame
The frame is use for supporting the part member use in this project. Frame’s
specification is in above the table.
Figure No. 3 Frame

5.3.2 Specifications of Ground wheel:
Sr. No. Details Size
1 Diameter 500mm
2 Width 40mm
3 Thickness 3mm
4 Shaft diameter 20mm
5 Length of shaft 700mm
6 Distance between two
wheel
650mm
Table No. 3 Specification of Ground Wheel
Ground wheel is use for the travelling like one field to another field. Specification of
ground wheel is in above the table.
Figure No. 4 Ground Wheel

5.3.3 Specifications of Idler shaft, Sprockets, Pulley, Bearing
&disk:
1 Diameter of shaft 20mm
2 Number of sprocket 4
3 Number of pulley 2
4 Number of teeth on two
larger sprockets
42
5 Number of teeth on smaller
sprockets
14
6 Diameter of pulley 90mm
7 Number of bearing 8
8 Diameter of disc 90mm
Table No. 4 Specification of Idler shaft, Sprocket, Pulley,
Bearing& Disc
5.3.4 Shaft:
Figure No. 5 Shaft

5.3.5 Sprockets:
Figure No. 6 Sprockets
A wheel that has a row teeth around its edge which fit into the holes of something
and cause it to turn when the wheel turns also any one of the teeth on such a wheel.
A cylinder with teeth around the circumference at either ends that project through
perforations in something to move it through a mechanism.
Sprocket is fitted on shaft and rotate to chain for cutting operation.
A chain drive is also rotated with the help of Sprockets.

5.3.6 Pulley:
Figure No. 7 Pulley
A pulley is a wheel on an axle or shaft that is design to support movement and
change of direction of a taught cable, rope or belt along its circumference. Pulleys are
used in a variety of ways to lift loads, apply forces, and to transmit power. In nautical
contexts, the assembly of wheel, axle, and supporting shell is referred to as a “block.”
A pulley may also be called a sheave or drum and may have a groove or grooves
between two flanges around its circumference. The drive element of a pulley system can
be a rope, cable, belt or chain that runs over the pulley inside the groove or grooves.
Hero of Alexandria identified the pulleys as one of six simple machines used to lift
weights.

Pulleys are assembling to form a block and tackle in order to provide mechanical
advantage to apply large forces. Pulleys are also assembled as part of belt and chain
drives in order to transmit power from one rotating shaft to another.
Figure No. 8 Flat belt on Pulley
A belt and pulley system is characterized by two or more pulleys in common to a
belt. This allows for mechanical power, torque and speed to be transmitted across axle. If
the pulleys are of differing diameters, a mechanical advantage is realized.
A belt drive is analogous to that of a chain drive, however a belt sheave may be
smooth so that the mechanical advantage is approximately given by the ratio of the pitch
diameter of the sheaves only, not fixed exactly by the ratio of teeth as with gears and
sprockets.
In the case of drum-style pulley, without a groove or flanges, the pulley often is
slightly convex to keep the flat belt centre. It is sometimes referred to as a crowned pulley.
Agriculture tractors built up to the early 1950s generally had a belt pulley for a flat belt. It
has been replaced by other mechanisms with more flexibility in methods of use such as
power take-off and hydraulics.

5.3.7 Bearing:
Figure No. 9 Bearing
A bearing is a machine element that constrains relative motion to only the desired
motion, and reduces friction between moving parts. The design of bearing may, for
example, provides for free linear movement of the moving part or for free rotating around a
fixed axis or, it may prevent motion by controlling the vectors of normal forces that bear on
the moving parts.
Many bearings also facilitate the desired motion as much as possible, such as by
minimizing friction. Bearings are classified broadly according to the type of operation, the
motion allowed, or to the directions of the loads applied to the parts.

 Plain bearing, also known by the specific styles: bushing, journal bearing, sleeve
bearing, rifle bearing, composite bearing.
 Rolling element bearing such as ball bearings and roller bearings.
 Jewel bearing, in which the load is carried by rolling the axle slightly off-centre.
 Fluid bearing, in which the load is carried by a gas or liquid.
 Magnetic bearing, in which the load is carried by a magnetic field.
 Flexure bearing, in which the motion is supported by a load element which bends.
In simple terms, roller bearings locate rotating components such as shafts or axles
within mechanical systems, and transfer axial and radial loads from the source of the load
to the structure supporting it.
To minimize friction, heat, power loss and wear, rolling elements such known as
rollers or balls with a circular cross-section are located between the races or journals of
the bearing assembly.
A wide variety of bearing designs exits to allow the demands of the application to be
correctly met for maximum efficiency, reliability, durability and performance.
The term “bearing” is derived from the verb “to bear”, a bearing being a machine
elements that allows one part to bear another. The simplest bearing are bearing surfaces,
cut or formed into a part, with varying degrees of control over the form, size, roughness
and location of the surface.
Other bearings are separate devices installed into a machine or machine part. The
most sophisticated bearings for the most demanding applications are very precise
devices; their manufacture requires some of the highest standards of current technology.

History:-
Figure No. 10 Tapered Roller Bearing
Figure No. 11 Drawing of Leonardo da Vinci

The invention of the rolling bearing, in the form of wooden rollers supporting, or
bearing, an object being moved is of great antiquity, and may predate the invention of the
wheel.
Though it is often claimed that the Egyptians used roller bearing in the form of tree
trunks under sleds, this is modern speculation. They are depicted in their own drawings in
the tomb of as moving massive stone blocks on sledges with liquid-lubricated runners
which would constitute a plain bearing.
There are also Egyptian drawings of bearings used with hand drills.
5.3.8 Disk:
Rotating disk is use to covert rotary motion of ground wheel to the reciprocating
motion of cutter blade.
Figure No. 12 Rotating Disk

5.3.9 Specifications of Handle:
1 Shape Hollow pipe
2 Diameter of Pipe 15mm
3 Length 900mm
4 Width 550mm
Table No. 5 Specification of Handle
5.3.10 Crop divider:
Figure No. 13 Crop Divider
 It’s also used for divide crops into two parts.
 Crop divider fitted in front of manually and power operated reaper machine.

5.3.11 Star wheel:
Conveys the cut grain from the cutter bar to the feeder belt drive. This is located
past the cutter bar.
Figure No. 14 Star Wheel
5.3.12 Specification of Star wheel:
Sr. no. Particulars Specifications
1 Outside diameter(Do) 200 mm
2 Inside diameter(Di) 152 mm
3 Internal diameter of star wheel(d) 25 mm
4 Material of star wheel Wood
Table No. 6 Specification of Star Wheel
5.3.13 Cutter bar:
Made up of the knife sections and hold-down clips. The cutter bar is positioned
along the front part of the reaper. It will cut the crop by shearing action.

Figure No. 15 Cutter Blade
5.3.14 Chain:
Chain & belt are used for the Power transmission.
Figure No. 16 Chain

Chain drive is way of transmitting mechanical power from one place to another. It is
often use to convey power to the wheels of a vehicle, particularly bicycles and
motorcycles. It is also used in a wide variety of machines besides vehicle.
Most often, the power is conveyed by a roller chain, known as the driver chain or
transmission chain, passing over a sprocket gear, with the teeth of the gear meshing with
the holes in the links of the chain. The gear is turned, and this pulls the chain putting
mechanical force into the system. Another type of drive chain is the Morse chain, invented
by the Morse chain company of Ithaca, New York, United States. This has inverted teeth.
Sometimes the power is output by simply rotating the chain, which can be used to
lift or drag objects. In other situations, a second gear is placed and the power is recovered
by attaching shafts or hubs to this gear. Through drive chains are often simple oval loops,
they can also go around corners by placing more than two gears along the chain; gears
that do not put power into the system or and transmit it out are generally known as idler-
wheels.
By varying the diameter of the input and output gears with respect to each other, the
gear ratio can be altered. For example, when the bicycle pedals gear rotate once, it
causes the gear that drives the wheels to rotate more than one revolution.
Advantages:-
 As no slip takes place during chain drive, hence perfect velocity ratio is obtained.
 Since the chains are made of metal, therefore they occupy less space in width than
a belt or rope drive.
 It may be used for both long as well as short distance.
 It gives high transmission efficiency.
 It gives fewer loads on the shaft.
 It has the ability to transmit motion to several shafts by one chain only.
 It transmits more power than belts.
 It permits high speed ratio of 8 to 10 in one step.
 It can be operated under adverse temperature and atmospheric conditions.

Dis-advantages:-
 The production cost of chains is relatively high.
 The chain drive needs accurate mounting and careful maintenance.
 Particularly lubrication and slack adjustment.
 The chain drive has velocity fluctuations especially when unduly stretched.
5.3.15 Belt:
Fig No. 17 Conveyor Belt
A belt is a looped strip of flexible material used to mechanically link two or more
rotating shafts. A belt drive offers smooth transmission of power between shafts at a
considerable distance.
Belt drives are used as the source of motion to transfer to efficiently transmit power
or to track relative movement.

Types of belt drives:-
In a two pulley system, depending upon the direction the belt drives the pulley, the
belt drives are divided into two types. They are open belt drive and crossed belt drive. The
two types of belt drives are discussed below in brief.
Open Belt Drives:-
Fig No. 18 Open Belt Drive
An open belt drive is used to rotate the driven pulley in the same direction of driving
pulley. In the motion of belt drive, power transmission results make one side of pulley
more tightened compare to the other side.
In horizontal drives, tightened side is always kept on the lower side of two pulleys
because the sag of the upper side slightly increases the angle of folding of the belt on the
two pulleys.

Crossed Belt Drives:-
Fig No. 19 Crossed Belt Drive
A crossed belt drive is used to rotate driven pulley in the opposite direction of
driving pulley. Higher the value of wrap enables more power can be transmitted than an
open belt drive.
However, bending and wear of the belt are important concerns.
Advantages:-
 Belt drives are simple are economical.
 They don’t require parallel shafts.
 Belt drives are provided with overload and jam protection.
 Noise and vibration are damped out.
 Machinery life is increased because load fluctuations are shock-absorbed.
 They are lubrication-free.
 They require less maintenance cost.
 Belt drives are highly efficient in use.
 They are very economical when the distance between shafts is very large.

Dis-advantages:-
 In belt drives, angular velocity ratio is not necessarily constant or equal to the ratio
of pulley diameters, because of slipping and stretching.
 Heat buildup occurs.
 Speed is limited to usually 35 meters per second.
 Power transmission is limited to 370 kilowatts.
 Operating temperatures are usually restricted to 35 to 850C.
 Some adjustment of center distance or use of an idler pulley is necessary for
wearing and stretching of belt drive compensation.
5.3.16 Electric Motor:
Fig. 20 Electric Motor
It is used for transmit the power on shaft.
The electrical motor is an instrument, which converts electrical energy into
mechanical energy. According to faradays laws of electromagnetic induction, when a
current carrying conductor is placed in a magnetic field, I experience a mechanical force
whose direction is given by Fleming’s left hand rule.

Construction of DC Generator and DC motor are identical. The same DC machine
can be used as a generator or as a motor. When a generator is in operation, it is driven
mechanically and develops a voltage. The voltage is capable of sending current through
the load resistance. While motor action a torque is developed.
The torque can produced mechanical rotation. Motors are classified as Series
Wound and Shunt Wound Motors.

Chapter: - 6
Specification of Manually and Power Operated
Reaper
1 Type Manually and Power Operated
2 Source of power One person and Electric Motor
3 Machine suitability To harvest cereal crop
4 Machine dimensions
a. Length
b. Width
c. Height
1700 mm
450 mm
900 mm
5 Crop cutting unit
A Type of cutter bar Reciprocating knife section
B Length of cutter bar 300 mm
C Knife section Standard
D Type Trapezoidal
E Blade Serrated
F Length × height 76.2mm×85mm
G Angle between cutting edge
and axis of knife section(α)
31º
H Rake angle 22º
I Thickness of cutting edge 5-3 mm
J Pitch of serration 1-1.2 mm
K Clearance between knife and
twine guard
0.5-1 mm
L Material high carbon steel
6 Finger guard
A Type twine guard with lip
B Overall length 110mm
C Overall width 35mm
D Lip spacing 50mm
E Height of cutter bar above
ground level
75 mm
Table No. 7 Specification of Reaper

Chapter: - 7
Prototype Design of Manually and Power
Operated Reaper Machine
(A) Isometric View:
Fig. 21 Isometric View of manually and power operated reaper
(B) Front view:
There are two wheels used to maintain the balance, connected to the frame by the
shaft. Bearings are used for rotation of the shaft on which rotating discs are mounted in
fig.
Fig. 22 Front view of Manually and Power Operated Reaper

(C) Side view:
The shafts are containing larger and smaller sprocket connected with two end
bearing at upper side and lower side respectively. Power is transmitted with the help of
chains. A rotating disc is provided at lower shaft for giving power and speed to the cutter
bar. The main shaft provides the whole power to the cutter bar as shown in fig.
Fig. 23 Side view of Manually and Power Operated Reaper
(D) Top view:
With the help of the two idler shafts whole transmission of power carried out with
help of chain sprockets= mechanism of ratio of 1:9. The upper idler shaft contains the
conveyer belt mechanism for conveying of crop.
Fig. 24 Top view of Manually and Power Operated Reaper

Chapter: - 8
Modifications
1. Adding a blade on cutter bar:
The available speed of cutter bar is 8 reciprocating movement with one complete
rotation of rear wheel. It works successfully but there was clogging due to less number of
blades in pre design of reaper. Now, the clogging is not occurring as of a new blade is
reciprocating at clogging area where, one guard is already available. Before adding one
blade the extra guard is not included in working.
Fig. 25 Modification of Cutter Bar
The replacement of damaged cutting blades are also done for proper functioning of
cutting of crops without any trouble in movement of cutting bar and it helps to reduce
clogging and cutting losses.
2. Change in position of crop divider:
Angle of approach of divider is important as very high result in dozing of crop and
flatter position of divider is not suitable for a lifting of even partially lodged crop. This angle
has been optimizing at 22o. During pre-design of manually operated reaper, the crop
divider was having some errors. The crop was not divided properly. The crop was striking
to side cutting mechanism. So the position of the crop divider is shifted little towards left
side. Now crops are successfully divided without any damage to it.

Fig. 26 Modification of Crop Divider
3. Add conveyor mechanism to conveying the crop to the side of
machine:
For every harvesting machine, conveying mechanism is necessary for reducing
losses during harvesting. In pre-design of machine, there was absence of conveying
mechanism and due to this there was maximum harvesting losses occurred.
In new design of reaper, for reducing these losses the flat belt conveying
mechanism is mounted as shown in plate no.3.15. Using rear wheel power, conveyor
works successfully. Four pulleys are used for completing conveying mechanism and
rubber belt is used for transferring the power from one pulley to second pulley. Third
pulley attached to a same shaft of second pulley. The conveying belt is placed on third
pulley and fourth as shown in plate no.3.15. The sheet metal is used for carrying blade as
shown in plate no.3.15.

Fig. 27 Modification of Conveyor
4. Star wheelspeed and inclination:
The minimum required speed of star wheel based on simple geometry is expressed as
Vs = Vm cosα
Where,
Vs = average speed of star wheel, kmph
Vm= machine working speed, kmph
α = angle of inclination of star wheel.
Optimum value of to give inclination of star wheel to give angle of approach suitable
for lifting of the crop is about 22o for this value above equation can be simplified as
Vs = 1.08 × Vm
= 1.08 × 1.8 = 1.94 kmph
This optimize between shattering at higher speed and choking at lower speed. On
the basis of this, we have design star wheel.

Chapter: - 9
Field Performance
Sr. No.
1 Time of start 11:00 am
2 Time of finish 11.15 am
3 Actual field operation 15 min.
4 Time lost owing to a. Turning b. Clearing
and clogging
1 min. 4 min.
5 Actual area covered 100 sq. m
6 Effective working width 300 mm
7 Effective field capacity 0.055 ha/hr
8 Field efficiency 66.13 %
9 Speed of machine 0.5 m/s
10 Height of cut 75 mm
11 Labour required 2
12 Length 10 m
13 Width 10 m
14 Area 100 m2
15 Type of soil Black cotton soil
Table No. 8 Field Performance

Chapter: - 10
Pre-testing Observation
Field selection:
The harvesting is done in well matured crop with maintained row to row distance.
That is at least fine textured, smooth, relatively leveled soil.
Height of crop plant:
For the cutting purpose, the height of crop plant must be more than 10-15cm.
Inclined angle of crop plant:
Inclined angle of crop plant shows inclined angle from vertical line.
i. Moisture content of steam and grain at the time of harvesting
Moisture content of steam and grain at the time of harvesting must be
measured.
ii. Area and shape of test field
iii. Soil moisture
iv. Condition of machine and operator
- Adjustment of working part of machine.
- Operating speed.
- Skill of operator

Chapter: - 11
Advantages
11.1 Advantages:
 Eco- friendly.
 No need of any power source at manually operated.
 Less cost.
 No labour required for cutting.
 Mostly suitable for small farm owner.
 Easy to handle & operate.
 Less maintenance.
 Less time required compare to sickle.
 Also use for grass cutting.
 Easy to afford for poor farmer.
 Good field performance.

Chapter: - 12
Limitations & Application
12.1 Limitation:
 Not suitable for large farm.
 The force requirement is high due to its weight.
 It’s more costly because of electric motor.
12.2 Application:
 It is use for rice cutting.
 Wheat cutting.
 Grass cutting.

Chapter: - 13
Cost Estimating
Sr No. Component No. of Component Price
1 Frame 1 550
2 Shaft 4 350
3 Disk 1 80
4 Sprockets 4 150
5 Chain 2 80
6 Pulley 4 220
7 Belt 2 200
8 Star Wheel 2 100
9 Crop Divider 2 80
10 Bearing 8 650
11 Handle 1 180
12 Ground Wheel 3 250
13 Electric Motor 1 1500
14 Fabrication Work - 2000
15 Total Cost - 6390
Table No. 9 Cost Estimating

Chapter: - 14
Importance
This project is to help small-scale farmers to meet an increased demand for local
grains, by designing a reaper machine to harvest grains more efficiently. Our research
work will focusing on ease of harvesting operation to the small land holders for harvesting
varieties of crop in less time and at low cost by considering different factors as power
requirement , cost of equipment , ease of operation , field condition , time of operation and
climatologically conditions. The operating, adjusting and maintaining principle are made
simple for effective handling by unskilled operators.

Chapter: - 15
Future Scope
This is a manually and power operated reaper. It works on Work energy and
Electrical energy. In this manually and power operated reaper when, electric motor is
failed to start so, we can operated it manually and we use chain drive in this reaper.

Chapter: - 16
Conclusion
After modification of manually and power operated reaper it work continuously and
gives more efficiency than the machine before modify. Conveying mechanism now helps
to stop clogging and decreases the cutting losses. Continuous working leads to harvest
crop in less time with minimum man power. Based on analysis of results following
conclusion are drawn: The Manually and power operated reaper is high labour saving
equipment requiring only 20 man-hr/ha. The cost of harvesting with this manually and
power operated reaper is 1250.4 Rs/ha and that with traditional method is 2000 Rs/ha.
The cost of reaper is low so it is affordable to small farmers. The field efficiency is
satisfactory which more than 66%, it increases from 59% due to its modifications.
Harvesting mechanization for main crops-an urgent demand of agricultural goods
production. Main achievements: research, design, manufacturing and wide application of
axial-flow threshers, vertical conveyor reapers and corn sellers. The study and
manufacturing of rice combine harvester with one-step harvesting technology has been
carried out by many individuals, mechanical firms as well as scientific institutes.
Models like GLH – 0.2 and GLH – 0.3A finished with relatively perfectiveness, but
haven't been mass-produced. Harvesting mechanization for main crops is a large and
complex field of science and technology, the international cooperation is essential to
satisfy the increasing demand of production.

Chapter: - 17
References
 www.google.co.in
 www.wikipedia.org
 www.youtube.com
 www.harvester.com

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