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CONSTRUCTION

The manufacturing & designing of suitable machinery for rural

industrialization will help in better production improve productivity more

employment. The designing & manufacturing of viable, economic machinery is the

necessary of the have in rural economy.

Our project should be such that its operation should be simple, its running &

maintenance expenses should be law. It should wor with minimum economic input

& its depreciation cost is low.

It should provide better techni!ue of topping and cutting of root an leaf of

onion with minimum cost by giving a better result.There are different parts used in machine " system.

#$ %otor drive

$ 'ulley driven

($ One pair shaft

)$ %etal frame.

*$ +utter

$ +hain conveyor

2.1. FRAME:

-ig .# -rame

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In our project firstly we mae s!uare tube frame on which owe other parts are

assemble.On the frame there is a longer shaft is mounted horizontally. & it is

mounted in plumber bloc at the base motor is mounted horizontally & drive is

passed through pulleys.

2.2. TRANSMISSION SYSTEM:

The mechanical power produced by prime mover we used to drive various

machines in the worshop & factories. transmission system is the mechanism

which deals with transmission of power & motion from prime move to shaft or from

one shaft to the other.

-ig . /haft

The rotary motion of the one pulley is transmitted to the operative element to

provide on operative woring or auxiliary motion. 0hen the re!uired motion is

rotary1 the transmission taes place through mechanisms transfer rotary motion from

one shaft to another. Transmission of the motion from the external source i.e.

electrical energy to the operative element can tae place trough mechanical elements

such as belts, chain etc.

The belt drive is one of the most common effective devices transmission

motion & power from one from one shaft to the other by means of then inextensible

belt over running over pulleys.

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-ig #.( 2riven 'ulley

0hen the centre distance between the two shafts is large than the tight side of

the belt should be the lower one the pulley called driver is mounted on the driving

shaft while the shaft while the other which is mounted on the shaft to which power is

to be transmitted is called the driven pulley.

0hen the belt moves over the pulley there is always the possibility of

slipping between the belt & pulley & hence the character of the motion transmitted is

not positive when positive action is re!uired.

In our project the electromagnetic operate by battery. The battery is mounted

at the middle part. The battery is most common form of electrical storage. 3atteries

can store & deliver only 2. +. power. 4nless on inventor is used to convert 2. +. to

. +. Only 2. +. appliances can be operated from the stored power. The battery

voltage must be the same as the voltage needed to run appliances.

/tandard battery voltage is or # volts. -or on appliance re!uiring ) volts,

two # volts or four volt battery connected is re!uired in series. They can be filly

charged & discharged while standard lead acid batteries 5ex. automobile type$

cannot. Then fully charged battery supply gives better effect on electromagnet.

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Cup belt conveyor

The belt runs supported by a pulley and a sheave. The pulley is driven by the motor.

The desired pulley rotation speed, i.e. the desired topping onion, is achieved by the

selection of a suitable gear ratio. The onions rest against the cups in the rising portion

of the belt, and after passing the sheave the onions fall out of the cups and remain

resting against the outer surface of the preceding cup in the descending portion of the

belt. The 46 profile tube protecting the conveyor retains the onions in place until they

arrive at the dropping point.

7owever, there are certain problems involved with the cup conveyors of the onion

cutter type described above.

The cup size is usually relatively large in proportion to the onion being conveyed, in

order that the onion should certainly remain in the cup in the rising portion of the

belt. 8specially if relatively small seed onions are used, there are easily left several

onions in one and the same cup, the conveyor, i.e. the elevator, must be relatively

high. This, again, affects the size of the apparatus.

t the sheave the onions may tend to be flung out by centrifugal force, especially athigh rotation speeds.

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t the point at which the onion is dropped the size of the onion affects its precise

time of being dropped. 0hen a cup arrives at the pulley, a small onion detaches

easily from between the horn wall and the cup bottom, whereas a large onion remains

there longer

It is a particular object to provide a cup conveyor in which no excess onions are left

during the feeding step, whereby a high elevator is avoided. 3y means of a conveyor

according to the project it is also possible to drop the onions into the furrow at

exactly the right moment, regardless of their size.

The project thus relates to a cup conveyor for a onion cutter, the conveyor being

intended for conveying the onion to be sorted from the onion feeding point to the

point at which it is dropped into the furrow, the conveyor comprising a pulley, a

sheave and, running on these wheels, a belt e!uipped with successive cups. The

project is characterized in that in connection with or in the vicinity of the cups there

are fitted flaps, and that each cup, and the corresponding flap, is arranged to eep a

onion in a holding grip to the point at which the intention is to drop the onion into the

furrow.

!ESI"N

2esign consists of application of scientific, principles, technical information

and imagination for development of new or improvised machine or mechanism to

perform a specific with maximum economy & efficiency.

7ence a careful design approach has to be adopted. The total design wor has

been split up into two parts1

/ystem design

%echanical 2esign

/ystem design mainly concerns the various physical constraints and

ergonomics, space re!uirements, arrangement of various components on main frame

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at system, man 9 machine interaction, :o. of controls, position of controls, woring

environment of machine, chances of failure, safety, measures to be provided,

servicing aids, ease of maintenance, scope of Improvement, weight of machine from

ground level, total weight of machine and a lot more.

In mechanical design the components are listed down and stored on the basis

of their procurement, design in two categories namely,

2esigned 'arts

'arts to be purchased

-or designed parts detached design is done & distinctions thus obtained are

compared to next highest dimensions which are readily available in maret. This

amplifies the assembly as well as postproduction servicing wor. The various

tolerances on the wors are specified. The process charts are prepared and passed on

to the manufacturing stage.

The parts which are to be purchased directly are selected from various

catalogues & specified so that anybody can purchase the same from the retails shop

with given specifications.

$.1. SYSTEM !ESI"N:

In system design we mainly concentrated on the following parameters;6

$.1.1. Sy%te& Select'on ()%e* on +,y%'c)l Con%tr)'nt%:

0hile selecting any machine it must be checed whether it is going to be

used in a large < scale industry or a small scale industry. In our case it is to be used

by a small scale industry ./o space is a major constrain. The system is to be very

compact so that it can be adjusted to corner of a room.

The mechanical design has direct norms with the system design. 7ence the foremost

job is to control the physical parameters, so that the distinctions obtained after

mechanical design can be well fitted into that.

$.1.2. Arr)n-e&ent% o /)r'ou% Co&ponent%:

=eeping into view the space restrictions the components should be laid such

that their easy >emoval or servicing is possible. %ore over every component should

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be easily seen none should be hidden. 8very possible space is utilized in components

arrangements.

$.1.3. Co&ponent% o Sy%te&:

s already stated the system should be compact enough so that it can be

accommodated at a corner of a room. ll the moving parts should be well closed &

compact. compact system design gives a high weighted structure which is desired.

%an %achine Interaction

The friendliness of a machine with the operator that is an important criteria of

design. It is the application of anatomical & psychological principles to solve

problems arising from %an < %achine relationship. -ollowing are some of the topics

included in this section. 2esign of foot lever 8nergy expenditure in foot & hand

operation ?ighting condition of machine.

$.1.. C,)nce% o F)'lure:

The losses incurred by owner in case of any failure are important criteria of

design. -actor safety while doing mechanical design is ept high so that there are

less chances of failure. %oreover periodic maintenance is re!uired to eep unit

healthy.

$.1.#. Serv'c'n- F)c'l'ty:

The layout of components should be such that easy servicing is possible.

8specially those components which re!uire fre!uents servicing can be easily

disassembled. /cope of -uture Improvement rrangement should be provided to

expand the scope of wor in future.

/uch as to convert the machine motor operated1 the system can be easily

configured to re!uired one. The die & punch can be changed if re!uired for other

shapes of notches etc.

$.1.$. 0e'-,t o M)c,'ne ro& "roun*:

-or ease and comfort of operator the height of machine should be properly

decided so that he may not get tried during operation. The machine should be slightly

higher than the waist level, also enough clearance should be provided from the

ground for cleaning purpose.

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$.1.. e'-,t o M)c,'ne:

The total weight depends upon the selection of material components as well

as the dimension of components. higher weighted machine is difficult in

Transportation & in case of major breadown1 it is difficult to tae it to worshop

because of more weight.

$.1.. Mec,)n'c)l !e%'-n:

%echanical design phase is very important from the view of designer as

whole success of the project depends on the correct design analysis of the problem.

%any preliminary alternatives are eliminated during this phase 2esigner

should have ade!uate nowledge above physical properties of material, loads

stresses, deformation, and failure. Theories and wear analysis. 7e should identify the

external and internal force acting on the machine parts.

This force may be classified as1

#@ 2ead weigh forces

@ -riction forces

(@ Inertia forces

)@ +entrifugal forces

*@ -orces generated during power transmission etc.

2esigner should estimate these forces very accurately by using design

e!uations. If he does not have sufficient information to estimate them he should

mae certain practical assumptions based on similar conditions. This will almost

satisfy the functional needs. ssumptions must always be on the safer side.

/election of factors of safety to find woring or design stress is another

important step in design of woring dimensions of machine elements. The

corrections in the theoretical stress value are to be made according in the inds of

loads, shape of parts & service re!uirements.

/election of material should be made according to the condition of loading

shapes of products environments conditions & desirable properties of material.

'rovision should be made to minimize nearly adopting proper lubrications

methods.

In, mechanical design the components are listed down & stored on the basis

of their procurement in two categories.

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2esign parts

'arts to be purchased

-or design parts a detailed design is done & designation thus obtain are

compared to the next highest dimension which is ready available in maret.

This simplification the assembly as well as post production service wor. The

various tolerances on the wor are specified. The processes charts are prepared &

passed on to the wor are specified.

The parts to be purchased directly are selected from various catalogues &

specification so that anybody can purchase the same from retail shop with the given

specifications.

$.2. MOTOR SE4ECTION

The operation speed of the is about *oo rpm, hence the power re!uirement of

the machine can be analyzed as follows,

Tor!ue re!uired at the shaft A *BB :6mm A .* :6m

Power=p=2NT

60

0here1 T A Tor!ue at spindle 5:m$

' A 'O08> 5=w$

:A/peed 5rpm$

p=2 5002.5

60

' A #(B .C* watt

+onsidering efficiency of belt drive DB E power re!uired A #DB watt

Motor Select'on

#6'hase Induction %otor 5 'ole $

(BFolts, *B 7p 5 B.#C =w$

/peed A #))B rpm 5 /ynchronous $

-rame /ize A D#

+urrent A #.DB mp

Tor!ue A O.#D =g.m

T8-+ +onstruction.

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$.2.1. Tor6ue An)ly%'%:

Tor!ue at spindle is given by

p=2NT

60

0here1

T A Tor!ue at spindle 5:m$

' A 'ower 5=w$

: A /peed 5rpm$

T=18060

2 500

T=3.437Nm

+onsidering *E overload1

Tdesign=1.25T

A#.* (.)(D

4.296Nm

Tdesign=4.296Nm

$.3. !ESI"N OF (E4T !RI/E FOR MAC0INE S+IN!4E:

/election an open belt drive using F6 belt1

>eduction ratio A1440

500 A .CC

'lanning a # stage reduction1

/tage

$ %otor pulley 52#$ A*B mm

3$ %ain shaft pulley 52$ A#*B mm

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$.3.1. Input !)t):

Input 'ower A B.#C =0

Input /peed A #))B >pm

+enter 2istance A (BB mm

%ax 3elt /peed A #BB m"min A.D m"sec

Groove ngle 5$ A 40

+oefficient Of -riction A B.*

3etween 3elt and 'ulley

llowable Tensile /tress A .* :"mm

$.3.2. Sect'on o (elt Select'on:5>ef '/G 2esign 2ata 'g :o.D.*C$

Table no..#./ection of 3elt /election

+"/

/ymbol

4sual

?and Of 2rive

5=0$

:ominal

Top 0idth

05mm$

:ominal

Thicness

T5mm$

0eight %eter

=gf

B.D*6* #( C B.#B

sin=R2R1

x =

D2D1

2x

sin=150502300

=9.59

ngle of lap smaller pulley1 i.e. motor pulley

=1802

18029.59

=160.82

=2.793

:ow,

%ass of belt " meter length A B.#Bgf

+entrifugal Tension 5Tc$ % v2

Tc=0.10626.672

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Tc=75.397N

%ax Tension in belt 5T$ A fall Area

A .* 104

A B N/mm2

Tension In Tight /ide Of 3elt A T1 A T 6 Tc

A B 6 D*.(HD

T1 A #C) :

Tension In /lac /ide Of 3elt A T2

2.3log [T1T2]=cosec( ) 0.252.8cosec (20 )

log [T1T2]=0.86

[ T1T2]=7.27T2=25.28N

'ower Transmitting +apacity of 3elt

P=(T1T2 ) vP=(18425.28)26.67

P=4.23 kw

3elt can safely transmit B.#C 0 power.

$.3.3. 4en-t, o (elt:

L=2 (x )+ (D2+D1 )

2

+

[(D2D1 )

2

x

]L=2 (300)+

(150+50 )2

+ (15050 )2

300

L=922.49mm

? AH(B mm

$.3.. Select'on o (elt:

/election of belt 6 (CJ from /T2 manufacturerJs catalogue%=8; 'IK

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Table no.. >esult Table

# 3elt /elected 6 (

Tight side Tension T# A #C) :

( /lac side Tension T A *.C :

) %otor pulley diameter 52#$ 2#A *B mm

* 'ulley diameter 52$ 2 A #*B mm

$.3.#. !ESI"N OF MAIN S+IN!4E:

Tdesign A (.C :m

A (.C x 103 :.mm

/election of main spindle material 5>ef;'/G 2esign 2ata 'g :o.;6 #.#B & #.#.#.#D$Table no..( 2esign of %ain /pindle

2esignation4ltimate Tensile

/trength 5:"mm$

Lield strength

5:"mm$

8: )5)B :1 cr #%oC$ DB BB

4sing /%8 code of design

llowable shear stress1

sall Is given stress1

sall A B.(B x !"#

A B.(B x B

A #CB:"mm

sall A B.#C x !$l#

A B.#C xDB

A #(B :"mm

+onsidering minimum of the above values1

sall A#(B :"mm

s, we are providing ey way on shaft1

>educing above value by *E

sall AB.D* x #(B

A HD.* :" mm

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a$ +onsidering pure torsional load1

Tdesign= sall d

3

16

d3=Tdesign16

sall

d3=

4.2910316

97.5

d3=224.09

d=6.0739mm

/electing minimum diameter of spindle A # mm from ease of +onstruction

because the standard pulley has a pilot bore of #.* mm in as cast condition, and a

bore of minimum # mm for eyway slotting operation.

3ut, /haft is also subjected to bending loads1 due to tensions in tight side and

slac of pulley and weight of magnetic die supporter.

Tension in Tight /ide of 3elt 5 T1 $ A #C) :

Tension in /lac /ide of 3elt 5 T2 $ A *.C :

orce=m g

orce=39.81

orce=29.43N

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-ig..# ?oading & 3ending 2iagram

"=0RA+R%=(T1T2 )+29.43

RA+R%=188.15N

&A=0RA 0=50158.72+29.43310 R% #D*

R%

=97.48N

RA=90.66N

%ax bending moment A 7.936103Nmm

8!uivalent Tor!ue1

Te=&'2+T

2

Te=(7.936103 )2+(4.29103 )

2

Te=9.0213103Nmm

1#

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sac#=16Te

d3

sac#=

169.0213(103

203

sac#=6.4179N

mm2

s sac#

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/electing1 single >ow deep groove ball bearing as follows1

/eries

Table no. .) /election of 3earing

I / I :o.3earing of 3asic design

:o. 5 /=- $2 2# 2 2 3 3asic +apacity

B 3+B 'lummer 3loc B )D )# #) #BBBB **B

' A K r 9 L a

-or our application -a A o

' A K r

0here r A B).* :

s1

r M eK A #

' A r

%ax radial load A r A B).* :

' A B).* :

+alculation dynamic load capacity of bearing

L=()P )a

0here, aA( for ball bearings

0hen ' for ball 3earing

-or m"c used for eight hr of service per day1

L* A #BBB6 BBBB hr

L=60n L

*

106

L=600 %rev

:ow1

600=)

3

204.53

)=1724.8N

s the re!uired dynamic capacity of bearing is less than the rated dynamic

capacity of bearing.

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(e)r'n- '% %)e.

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MANUFACTURIN" 8 FA(RICATION

Table no. D.# %anufacturing & -abrication

/r.

:o.'art :ame 2imensions

#. 'lummer 3loc

Inner 2ia.A

Bmm

?ength6

#*mm

7eight6

Bmm

. 2riven 'ulley

Outer

2ia.A#*Bm

mInner

2ia.ABmm

(. F63elt Type63HB

%aterial6'olyester

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a

b

h

+ord

). 2river 'ulleyInner

2iameterAB

mm

GroovengleA

40

*. /hafts2iameter of

shaftABmm

27