INTERNATIONAL JOURNAL OF PROFESSIONAL ...ijpres.com/pdf39/5.pdfINTERNATIONAL JOURNAL OF PROFESSIONAL ENGINEERING STUDIES Volume 10 /Issue 1 / MAY 2018 IJPRES B. Noncontact Scanners

INTERNATIONAL JOURNAL OF PROFESSIONAL ENGINEERING STUDIES Volume 10 /Issue 1 / MAY 2018

IJPRES

SPUR GEAR DEVELOPMENT USING RAPID PROTOTYPING BY REVERSE ENGINEERING 1 SAMBASIVARAO, 2 Mr. SHAIK RAFI

1 UG Scholar, Dept of MECH, NALANDA INSTITUTE OF TECHNOLOGY, Village: KANTEPUDI,

SATTENAPALLI(M), GUNTUR(Dist), A.P, India, Pin: 522438.

Email id: [email protected] 2 Assistant professor, Dept of MECH, NALANDA INSTITUTE OF TECHNOLOGY, Village: KANTEPUDI,

SATTENAPALLI(M), GUNTUR(Dist), A.P, India, Pin: 522438.

ABSTRACT

This project is about application of reverse

engineering. Reverse engineering helps in obtaining

the geometry of part or product which is not available

otherwise. Its application makes it possible to

reconstruct the original component with its drawing

and manufacturing process. In this project we are

going to produce spur gear used in automobile by

Reverse Engineering. The procedure includes various

stages which will help understand the different

phases of reverse engineering.

The process starts with understanding the reverse

engineering procedure. The part geometry is first

obtained with the help of scanning technology. Then

with the use of different softwares, the three-

dimensional model of the spur gear is obtained. Once

the CAD model is obtained the part is analyzed using

SOLIDWORKS simulation tool. After the optimized

geometry is obtained, the pattern of the part is

obtained using Rapid prototyping machine. This can

be used for casting of the original part.

INTRODUCTION

In today’s intensely competitive global market,

product enterprises are constantly seeking new ways

to shorten lead times for new product developments

that meet all customer expectations. In general,

product enterprise has invested in CAD/CAM, rapid

prototyping, and a range of new technologies that

provide business benefits. Reverse engineering (RE)

is now considered one of the technologies that

provide business benefits in shortening the product

development cycle. Figure 1.1 below depicts how RE

allows the possibilities of closing the loop between

what is “as designed” and what is “actually

manufactured”.

What Is Reverse Engineering?

Engineering is the process of designing, , assembling,

manufacturing and maintaining products and

systems. There are two types of engineering, forward

engineering and reverse engineering. Forward

engineering is the traditional process of moving from

high-level abstractions and logical designs to the

physical implementation of a system. In some

situations, there may be a physical part/ product

without any technical details, such as drawings, bills-

of-material, or without engineering data. The process

of duplicating an existing part, subassembly, or

product, without drawings, documentation, or a

computer model is known as reverse engineering.

Reverse engineering is also defined as the process of

obtaining a geometric CAD model from 3-D points

acquired by scanning/ digitizing existing

parts/products.

Fig.1: Product development life cycle

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The process of digitally capturing the physical

entities of a component, referred to as reverse

engineering (RE), is often defined by researchers

with respect to their specific task (Motavalli &

Shamsaasef 1996). Abella et al. (1994) described RE

as, “the basic concept of producing a part based on an

original or physical model without the use of an

engineering drawing”. Yau et al.(1993) define RE, as

the “process of retrieving new geometry from a

manufactured part by digitizing and modifying an

existing CAD model”. Reverse engineering is now

widely used in numerous applications, such as

manufacturing, industrial design, and jewelry design

and reproduction For example, when a new car is

launched on the market, competing manufacturers

may buy one and disassemble it to learn how it was

built and how it works. In software engineering, good

source code is often a variation of other good source

code. In some situations, such as automotive styling,

designers give shape to their ideas by using clay,

plaster, wood, or foam rubber, but a CAD model is

needed to manufacture the part. As products become

more organic in shape, designing in CAD becomes

more challenging and there is no guarantee that the

CAD representation will replicate the sculpted model

exactly.

Fig.2: Physical-to-digital process

REVERSE ENGINEERING –THE GENERIC

PROCESS:

The generic process of reverse engineering is a three-

phase process as depicted in Figure.

Fig.3: Reverse engineering- the generic process

SCANNING:

This phase is involved with the scanning strategy–

selecting the correct scanning technique, preparing

the part to be scanned, and performing the actual

scanning to capture information that describes all

geometric features of the part such as steps, slots,

pockets, and holes. There are two distinct types of

scanners, contact and noncontact.

A. Contact Scanners

These devices employ contact probes that

automatically follow the contours of a physical

surface .In the current market place, contact probe.

Fig.4: Contact scanning touch probe.

Scanning devices are based on CMM technologies,

with a tolerance range of +0.01 to 0.02 mm.

However, depending on the size of the part scanned,

contact methods can be slow because each point is

generated sequentially at the tip of the probe.

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B. Noncontact Scanners

A variety of noncontact scanning technologies

available on the market capture data with no physical

part contact. Noncontact devices use lasers, optics,

and charge-coupled device (CCD) sensors to capture

point data, as shown in Figure. Although these

devices capture large amounts of data in a relatively

short space of time, there are a number of issues

related to this scanning technology.

• The typical tolerance of noncontact scanning is

within ±0.025 to 0.2 mm.

• Some noncontact systems have problems generating

data describing surfaces, which are parallel to the

axis of the laser.

Fig.5: Optical scanning device. Originally published

in Rapid Prototyping Casebook, McDonald, J.A.

Fig.6: Vertical faces–touch probe versus a laser.

POINT PROCESSING

This phase involves importing the point cloud data,

reducing the noise in the data collected, and reducing

the number of points. These tasks are performed

using a range of predefined filters. It is extremely

important that the users have very good

understanding of the filter algorithms so that they

know which filter is the most appropriate for each

task.

This phase also allows us to merge multiple scan data

sets. Sometimes, it is necessary to take multiple scans

of the part to ensure that all required features have

been scanned. This involves rotating the part; hence

each scan datum becomes very crucial. Multiple scan

planning has direct impact on the point processing

phase.

APPLICATION GEOMETRIC MODEL

DEVELOPMENT

In the same way that developments in rapid

prototyping and tooling technologies are helping to

shorten dramatically the time taken to generate

physical representations from CAD models, current

RE technologies are helping to reduce the time to

create electronic CAD models from existing physical

representations. The need to generate CAD

information from physical components will arise

frequently throughout any product introduction

process. The generation of CAD models from point

data is probably the most complex activity within RE

because potent surface fitting algorithms are required

to generate surfaces that accurately represent the

three-dimensional information described within the

point cloud data sets. Most CAD systems are not

designed to display and process large amounts of

point data; as a result new RE modules or discrete

software packages are generally needed for point

processing.

INTRODUCTION TO POWER

TRANSMISSION

Power transmission states that speed and torque

conversions from rotating power source to other

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device. Here in our project we design and analysis

the intermediate shaft for stress and deflection, it is

necessary to know the applied forces. If the forces are

transmitted through gears, it is necessary to know the

gear specifications in order to determine the forces

that will be transmitted to the shaft. But stock gears

come with certain bore sizes, requiring knowledge of

the necessary shaft diameter. This project will focus

on an overview of a power transmission system

design, demonstrating how to incorporate the details

of each component into an overall design process.

Fig.7: Compound reverted gear train.

Transmission

The term power transmission is defined as the

movement of energy from a source to an output

device that performs work. In mechanical power

transmissions, a device is interposed between a

source of power and a specific application for the

purpose of adapting one to the other. Most

mechanical transmissions function as rotary speed

changers; the ratio of the output speed to the input

speed may be constant (as in a gearbox) or variable.

On variable-speed transmissions the speeds may be

variable in discrete steps or they may be continuously

variable within a range.

The need for a transmission in an automobile is a

consequence of the characteristics of the internal

combustion engine. Engines typically operate over a

range of 600 to about 7000revolutions per minute

(though this varies, and is typically less for diesel

engines), while the car's wheels rotate between 0 rpm

and around 1800 rpm.

TYPES OF POWER TRANSMISSION

SYSTEMS

Manual transmission

Manual transmissions come in two basic types:

A simple but rugged sliding-mesh or

unsynchronized/non-synchronous system,

where straight-cut spur gear sets spin freely,

and must be synchronized by the operator

matching engine revs to road speed, to avoid

noisy and damaging clashing of the gears.

The now common constant-mesh gearboxes,

which can include non-synchronized, or

synchronized/synchromesh systems, where

typically diagonal cut helical (or sometimes

either straight-cut, or double-helical) gear sets

are constantly "meshed" together, and a dog

clutch is used for changing gears. On

synchromesh boxes, friction cones or "synchro-

rings" are used in addition to the dog clutch to

closely match the rotational speeds of the two

sides of the (declutched) transmission before

making a full mechanical engagement.

Semi-automatic

A hybrid form of transmission where the integrated

control system handles manipulation of the clutch

automatically, but the driver can still - and may be

required to - take manual control of gear selection.

This is sometimes called a "clutchless manual," or

"automated manual" transmission. Many of these

transmissions allow the driver to fully delegate gear

shifting choice to the control system, which then

effectively acts as if it was a regular automatic

transmission. They are generally designed using

manual transmission "internals", and when used in

passenger cars, have synchromesh operated helical

constant mesh gear sets.

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Early semi-automatic systems used a variety of

mechanical and hydraulic systems - including

centrifugal clutches, torque converters, electro-

mechanical (and even electrostatic) and

servo/solenoid controlled clutches - and control

schemes – automatic declutching when moving the

gearstick, pre-selector controls, centrifugal clutches

with drum-sequential shift requiring the driver to lift

the throttle for a successful shift, etc. -and some were

little more than regular lock-up torque converter

automatics with manual gear selection.

Automatic

These primarily use hydraulics to select gears,

depending on pressure exerted by fluid within the

transmission assembly. Rather than using a clutch to

engage the transmission, a fluid flywheel, or torque

converter is placed in between the engine and

transmission. It is possible for the driver to control

the number of gears in use or select reverse, though

precise control of which gear is in use may or may

not be possible.

Automatic transmissions are easy to use. However, in

the past, automatic transmissions of this type have

had a number of problems; they were complex and

expensive, sometimes had reliability problems

(which sometimes caused more expenses in repair),

have often been less fuel-efficient than their manual

counterparts (due to "slippage" in the torque

converter), and their shift time was slower than a

manual making them uncompetitive for racing. With

the advancement of modern automatic transmissions

this has changed.

Fig.8: Epicyclic gear train

POWER TRANSMISSION DEVICES

Gear Drive

Chain drive

Belt Drive

GEAR TRAINS

A gear train is formed by mounting gears on a frame

so that the teeth of the gears engage. Gear teeth are

designed to ensure the pitch circles of engaging gears

roll on each other without slipping; this provides a

smooth transmission of rotation from one gear to the

next.

Gears trains are classified into following types Simple gear train Compound gear train Reverted compound gear train Planetary gear train

GEARS

Gear is a part, as a disk, wheel, or section of a shaft,

having cut teeth of such form, size and spacing that

they mesh with teeth in another part to transmit or

receive force and motion.

They can be applied between two shafts which are

Parallel Collinear Perpendicular and intersecting Perpendicular and nonintersecting Inclined at any arbitrary angle

METHODOLOGY USED FOR CASE STUDY OF GEAR A case study of Gear is done for the purpose of

obtaining point cloud data which was exported into

associate nursing .stl format of the CAD program.

The best method to approximate a 3D geometrical

model is by approximating it with lots of triangular

aspects.

A. The typical reverse engineering process can be

summarized in following steps:

1. Physical model which needs to be redesigned or to

be used as the base for new product.

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2. Scanning the physical model to get the point

cloud. The scanning can be done using various

scanners available in the market.

3. Processing the points cloud includes merging of

points cloud if the part is scanned in several settings.

The outlines and noise is eliminated. If too many

points are collected then sampling of the points

should be possible.

4. To create the polygon model and prepare .stl files

for rapid prototyping.

5. To prepare the surface model to be sent to

CAD/CAM packages for analysis.

6. Tool path generation with CAM package for

suitable CNC machine manufacturing of final part on

the CNC machine.

Fig.9: Front view of Gear which has to be produced

Fig.10: Side view of Gear which has to be produced

Fig.11: Back view of Gear which has to be produced

Fig.12: Isometric view of Gear which has to be

produced

The Gear has been scanned in a Roland Model lpx-

600 laser scanner .

Fig.13: Roland Model LPX-600 Laser Scanner

The Roland Model lpx-600 laser scanner is a medium

sized scanner used to scan object of maximum height

of around 150 mm and diameter of 120 mm. It

operates with interface of computer with software Dr.

Picza which helps in setting up the scanning

parameters and also shows the scanning process. It

stores the scanned file in .stl format

Once the scanned image of object is obtained using

scanner it is exported into .stl format shown in fig..

The parameter set in the above software decides the

quality of scanned image. As the time for scanning

increases the quality of scanned image improves.

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Fig.14: .stl Image File of Scanned Component

B. Obtaining the solid geometry from the point cloud data The original .stl data is scattered and contains some

noise around the boundary of model. The noise

creates a problem while generating a solid model so it

has to be cleaned from the data. Solid works software

has Scan to 3D option which help to point out the

noise from the data and with the help of noise

reduction tool the noise is reduced. Then we get a

clean .stl data which can be used for further

processing.

INTRODUCTION TO SOLID WORKS

Solid works mechanical design automation software

is a feature-based, parametric solid modeling design

tool which advantage of the easy to learn windows TM

graphical user interface. We can create fully associate

3-D solid models with or without while utilizing

automatic or user defined relations to capture design

intent.

Building a model in Solid Works usually starts with a

2D sketch (although 3D sketches are available

for power users). The sketch consists of geometry

such as points, lines, arcs, conics (except the

hyperbola), and spines. Dimensions are added to the

sketch to define the size and location of the

geometry. Relations are used to define attributes such

as tangency, parallelism, perpendicularity, and

concentricity. The parametric nature of Solid Works

means that the dimensions and relations drive the

geometry, not the other way around. The dimensions

in the sketch can be controlled independently, or by

relationships to other parameters inside or outside of

the sketch.

SOLIDWORKS SCAN TO 3D

Using the Solid Works software’s ScanTo3D

functionality, you can open scan data from any

scanner (mesh or point cloud files) or curve data from

mathematics software, prepare the data, then convert

it into a surface or solid model.

ScanTo3D significantly reduces the time required to

build complex 3D models from non-digital data.

Designers can use ScanTo3D for various purposes:

Medical designers - Create anatomical objects

for reference.

Fig.15: Example of a solid created from scanned data of a hand, using the Surface

Wizard's Automatic creation.

Consumer product designers - Create quick

representations of physical components made

from clay, foam, etc.

Machine designers - Create quick references to

OEM parts.

Two Methods for Converting Scan Data to a

Solid Model.

Semi-manual Creation: Direct Mesh Referencing

Direct mesh referencing is useful for very complex surfaces, such as consumer products.

Semi-automated Creation Using Wizards

The Mesh Prep and Surface Wizards guide you

through the ScanTo3D process

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MESH PREPARATION WIZARD

Mesh Prep Wizard - Welcome Property Manager

The Mesh Prep Wizard prepares and cleans up mesh or point cloud files. The wizard produces a mesh feature from which you can create surfaces and a solid model using direct mesh referencing or the Surface Wizard.

Orientation Property Manager

Align the mesh or point cloud feature to the global

origin and planes, which is important for accurate

downstream manipulation of the model.

Noise Removal Property Manager

For point cloud data, this tool divides the cloud into

partitions and removes points that are outside the

average distribution, resulting in the removal of noise

points.

Removing Noise From Point Clouds or Meshes

You can remove noise using the Noise Removal

Property Manager. Noise is defined as either points

that are outside the average distribution, or separate

mesh patches that are small in area.

Extraneous Data Removal Property Manager

Extraneous data typically exists in point cloud data

and comes from the fixture used to hold the part in

place while you scan it. Choose a tool to select

extraneous data, then click Delete to remove the data.

Mesh Boundaries

Mesh boundaries form along boundary edges.

ScanTo3D can create boundary curves only along

boundary edges. Boundary edges are commonly

found on meshes that represent surfaces or have large

holes in them.

SURFACE WIZARD CREATION MANAGER

Surface Wizard - Welcome Property Manager

The Surface Wizard converts a mesh feature into

surfaces and a solid model.

Solid/Surface Creation Property Manager

The Surface Wizard can automatically create surfaces

or guide you to create surfaces.

Automatic Creation

Automatically create solids based on the desired

amount of detail.

SURFACE EXTRACTION PROPERTY

MANAGER

Use this Property Manager to extract sub-meshes

from the model as surfaces. You later can convert the

surfaces into solids using the Solid Works surface

tools such as Trim, Knit, and Thicken. To manually

extract surfaces, select a sub-mesh, then select a

surface type under Face Settings.

Fig.16: Model before surface extraction Model after

extracting two cylindrical and two b-spline surfaces

When you extract surfaces, you might see salient sub-

meshes (arrows), which are transitions between

primary mesh regions. Transition regions usually

show a large variation in geometry, such as

curvature. You usually do not convert salient sub-

meshes as surfaces during guided surface creation,

but instead you create these surfaces later in Solid

Works.

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Fig.17: Extracted surfaces using ScanTo3D

Fig.18: Solid model created from the extracted

surfaces using Untrim, Trim, Extend,Knit,

and Thicken tools.

Exporting files:

After you import a mesh or cloud point file into a

Solid Works document using ScanTo3D, We export

the document as another file type that contains the

mesh or cloud point data.

1. Click File > Save As.

2. Select a file format in Save as type:

ScanTo3D (*.xyz)

ScanTo3D (*.wrl).

ScanTo3D (*.stl).

ScanTo3D (*.3ds)

ScanTo3D (*.iges)

The scanned file is imported in solid works software

which helps to extract geometry from the .stl file or

point cloud data shown in figure below to Solid

geometry.

Fig.19: .Stl file imported to solid works Scan to 3D

By using Mesh preparation wizard meshing of the

.Stl file is done.

Increasing the global smoothness then entering into

surface wizard manager for adjusting surface

resolution.

Fig.20: surface failure areas

Fig.21: individual sub meshes are identified

Now all the surface are extracted as shown below

Fig.22: surfaces extraction

Fig.23: model is completed with extra surfaces

Finally the base model is complete by using Trim,

knit ,fillets and chamfer options for generating solid

model. The file is saved in .STL format.

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Fig.24: Four views of the Gear

The drawings are generated for the Gear model and

the following dimensions are obtained.

Symbol Parameter Gear

m Module 1.79~2mm

b Face width 8.5mm

T No. of teeth 29

D Pitch circle

diameter

52mm

Profile 20° full depth involute

INTRODUCTION TO SOLIDWORKS

SIMULATION:

Solid Works® Simulation is a design analysis system

fully integrated with Solid Works. Solid Works

Simulation provides simulation solutions for linear

and nonlinear static, frequency, buckling, thermal,

fatigue, pressure vessel, drop test, linear and

nonlinear dynamic, and optimization analyses.

Powered by fast and accurate solvers, Solid Works

Simulation enables you to solve large problems

intuitively while you design. Solid Works Simulation

comes in two bundles: Solid Works Simulation

Professional and Solid Works Simulation Premium to

satisfy your analysis needs. Solid Works Simulation

shortens time to market by saving time and effort in

searching for the optimum design.

Fig.25: Simulation example

ANALYSIS STEPS :

The steps needed to perform an analysis depend on

the study type. You complete a study by performing

the following steps:

Create a study defining its analysis type and

options.

If needed, define parameters of your study. A

parameter can be a model dimension, material

property, force value, or any other input.

Define material properties.

Specify restraints and loads.

The program automatically creates a mixed

mesh when different geometries (solid, shell,

structural members etc.) exist in the model.

Define component contact and contact sets.

Mesh the model to divide the model into many

small pieces called elements. Fatigue and

optimization studies use the meshes in

referenced studies.

Run the study.

View results.

STRUCTURAL ANALYSIS OF GEAR USING

SOLIDWORKS SIMULATION TOOL

Structural analysis procedure:- The Structural

analysis involves the following

procedure:

- Pre-Processing: It include the description of the

geometry or model, the physical characteristics of the

model.

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Definition of type of analysis, material properties,

Loads and boundary conditions

- Solution: it involves the application of the finite

element analysis

- Run analysis to obtain solution (stresses).

- Post-Processing: It includes the visualization and

interpretation of the results of the solution.

PERFORMING STATIC ANALYSIS ON GEAR

The structural stress analysis of the gear tooth model

is carry out using the FEA in

Solid works simulation .The load applied at the

tooth of the gear by applying the analysis over the

tooth which is facing the load we get the stress

distribution in the numeric as well as in the form of

the color scheme.

Material Properties Alloy steel

Density = 7700 kg/m^3

Poison ratio = 0.28

Young' modulus = 2.1E+11 N/mm^2

Fixed:

Force: 500N

Mesh Information

Mesh type Solid Mesh Mesher Used: Standard mesh

Automatic Transition: Off Include Mesh Auto

Loops: Off

Jacobian points 4 Points Element Size 2.7397 mm

Tolerance 0.136985 mm Mesh Quality High

MESH INFORMATION - DETAILS

Total nodes = 27167

Total elements = 16148

STUDY RESULTS FOR FACE WIDTH 8.5 MM

Stress

Strain

Displacement

STUDY RESULTS FOR FACE WIDTH 10.5 MM

Stress

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Strain

Displacement

STUDY RESULTS FOR FACE WIDTH 12.5MM

Stress

Strain

Displacement

STUDY RESULTS FOR FACE WIDTH 14.5MM

Stress

Strain

Displacement

RESULTS AND DISCUSSIONS

The structural stress analysis of the gear tooth model

is carry out using the FEA in Solid works simulation.

The load applied at the tooth of the gear .by applying

the analysis over the tooth which is facing the load

we get the stress distribution in the numeric as well

as in the form of the color scheme. By varying the

face width and keeping the other parameters constant

various models of the gear are created. For

determining at any stage during the design of the gear

face width is an important parameter. The results of

the variation in face width from (8.5 mm to 14.5mm

)there is continuous decrement in the value of the

stress of the tooth of the gear stress. Results of

theoretical and static analysis are closer, therefore

the design are accepted. As it is seen clearly from all

tables and graphs the maximum bending stress values

are increase with the decrease of face width. In this

work we got on two results as follow

_ Theoretical results (from Lewis equation directly)

_ static analysis results

And all results are closer as shown in graphs.

Effect of face width :

The effect face width on maximum bending stress is

study by varying the face width for five values which

are (b=8.5mm, 10.5mm, 12.5mm, 14.5mm) the

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magnitude of the stresses obtained for those face

widths are displayed .

COMPARISION OF THEORETICAL STRESS

VALUES AND SOLIDWORKS VALUES

Face width

(mm)

Bending

stresses (MPa)

Lewis equation

Bending

stresses (MPa)

Static analysis

8.5 50.7 47.2

10.5 41.04 40.2

12.5 34.4 29.2

14.5 29.7 25.2

Table.1: Comparison of bending stresses

(theoretical and software )

Introduction to rapid prototyping

rapid prototyping (rp) can be defined as a group of

techniques used to quickly fabricate a scale model of

a part or assembly using three-dimensional computer

aided design (cad) data. what is commonly

considered to be the first rp technique, stereo-

lithography, was developed by 3d systems of

valencia, ca, usa. the company was founded in 1986,

and since then, a number of different rp techniques

have become available.

why rapid prototyping ?

the reasons of rapid prototyping are

• to increase effective communication.

• to decrease development time.

• to decrease costly mistakes.

• to minimize sustaining engineering changes

• to extend product lifetime by adding

necessary features and eliminating redundant

features early in the design.

rapid prototyping decreases development time by

allowing corrections to a product to be made early in

the process. by giving engineering, manufacturing,

marketing, and purchasing a look at the product early

in the design process, mistakes can be corrected and

changes can be made while they are still inexpensive.

the trends in manufacturing industries continue to

emphasize the following:

• Increasing number of variants of products.

• Increasing product complexity.

•Decreasing product lifetime before

obsolescence.

• Decreasing delivery time.

METHODOLOGY OF RAPID PROTOTYPING

The basic methodology for all current rapid

prototyping techniques can be summarized as

follows:

1. A CAD model is constructed, and then

converted to STL format. The resolution can be

set to minimize stair stepping.

2. The RP machine processes the .STL file by

creating sliced layers of the model.

3. The first layer of the physical model is created.

The model is then lowered by the thickness of

the next layer, and the process is repeated until

completion of the model.

4. The model and any supports are removed. The

surface of the model is then finished and

cleaned

PROTOTYPING OF THE GEAR USING

SELECTIVE LASER SINTERING

RAPIDPROTOYPING SYSTEM

FORMIGA P 100 - small, fast, efficient, e-

Manufacturing in the Compact Class Plastic laser-

sintering system for the direct manufacture of series,

spare parts and functional prototypes.

Fig:26: RP Systems

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TECHNICAL SPECIFICATIONS

TABLE NO – 1:

Effective building

volume

200 mm x 250 mm x 330

mm (7.9 x 9.8 x 13 in)

Building speed

(material-dependent)

up to 24 mm height/h (0.94

in/h)

Layer thickness

(material-dependent) typically 0.1 mm (0.004 in)

Support structure not necessary

Laser type CO2, 30W

Precision optics F-theta lens

Scan speed during

build process up to 5 m/s (16.4 ft/sec)

Power supply 16 A

Power consumption

(nominal) 2 Kw

Nitrogen generator integrated (optional)

Compressed air

supply

minimum 6,000 hPa; 10

m3/h (87 psi; 13.08 yd3/h)

TABLE NO – 2:

Machine with

powder

containers and

touch screen

1,320 mm x 1,067 mm x 2,204

mm

(51.97 x 42.01 x 86.77 in)

Recommended

installation space

3.2 m x 3.5 m x 3 m (126 x 137.8

x 118.1 in)

Weight Ca. 600 kg (1,323 lb)

Powder mixing

station

700 mm x 500 mm x 1,000 mm

(27.56 x 19.69 x 39.37 in)

Unpacking and

sieving station

1,200 mm x 700 mm x 1,500 mm

(47.24 x 27.56 x 59.06 in)

TABLE NO – 3:

PC current Windows operating system

Software EOS RP Tools; Magics RP

(Materialise)

CAD

interface

STL. Optional: converter to all

common formats

Network Ethernet

Certification CE

CONCLUSIONS

In theory of Gear, we are considering that the load

is acting at one point and the stress is calculated.

The calculation of maximum stresses in a gear at

tooth root is three dimensional problems. The

accurate evaluation of stress state is complex task.

The contribution of this thesis work can be

summarized as follows:

The strength of gear tooth is a crucial parameter to

prevent failure. In this work, it is shown that the

effective method to estimate the root bending stress

using three dimensional model of a gear and to

verify the accuracy of this method the results with

different face width of teeth are compared with

theoretical values.

The face width is an important geometrical

parameter in design of gear as it is expected in this

work the maximum bending stress decreases with

increasing face width.

REFERENCES

[1]. Cheng, Y., And Tasy C.B., Stress Analysis Of

Helical Gear Set With Localized Bearing

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structures, 49,pp.253-268,1993.

[3]. Huston, R.L., Mavriplis, D., Oswald, B.F., and

Liu Y.S., A Basis for Solid Modeling of Gear Teeth

With Application In Design And Manufacturing,

NASA Technical Memorandum

Gurmeet

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[4]. Zhang, J.J., East, I.I., Shi, And Y.H., Load

Analysis with Varying Mesh Stiffness, Computer

And Structures, 70, pp.273-280, 1999

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[7]. Hedlund, J., And Lethovaara, A., Modeling Of

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University Of Technology, Machine Design, P.O.

Box 589,33101 Tampere, Finland.

[8]. Vera, N.S., And Ivan, C., The Analysis Of

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Pp, 1055-1066, 2003.

[9]. Pushpendra Kumar Mishra, Dr. M. S. Murthy",

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Width of Helical Gear Obtained pp45-51, 2013.

[10]. Ajeet Kumar Rai and Mustafa S Mahdi, “A

Practical Approach to Design and Optimization of

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Issue 3, 2012, pp. 378 - 386, ISSN Print: 0976 –

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[11]. Ajeet Kumar Rai and Ashish Kumar, “A

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Applications”, International Journal of Advanced

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(IJARET), Volume 3, Issue 2, 2012, pp. 214 - 225,

ISSN Print: 0976-6480, ISSN Online:

0976-6499.

Gurmeet

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