ABSTRACT

A knuckle joint is used to connect two rods under tensile load. This joint permits misalignment of the rods and may take compressive load if it is guided. These joints are used for different types of connections. In this, one of the rods has eye at the rod end and the other one is forked with eyes at both the legs. A pin is inserted through the rod end eye and fork end eye is secured by a collar and a split pin. Screwed connections often play an important part in the transmission of load through machine assemblies. In large circuit breakers they are subjected intermittently to high impulsive loads transmitted to large scale linkages. The paper reports on design of a knuckle joint.

The modelling of a knuckle joint is performed by using CATIA V5 R20 package The knuckle joint takes compressive loads often, thus there is a need for quality design tools. The modelling of the knuckle joint is done using 3D software. Here we will be using CATIA V5 for modelling. This joint permits angular misalignment of the rods and may take compressive load if it is guided. These joints are used for different types of connections e.g. tie rods, tension links in bridge structure. In this, one of the rods has an eye at both the legs.

A pin is inserted through the rod-end eye and fork-end eyes and is secured by collar and a split pin. Screwed connections after play an important part in the transmissions of load through machine assemblies. In large circuit breakers they are subjected intermittently to high impulsive loads transmitted through large-scale linkages

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CHAPTER-1

INTRODUCTION

A knuckle joint is used to connect two rods which are under the action of tensile

loads. However, if the joint is guided the rods may support compressive load. A knuckle joint

may be readily disconnected for adjustments and repairs. Its use may be found in link of the

cycle chain , tie rod joint for roof truss, valve rod joint with eccentric load, pump rod joint,

tension link in bridge structure and lever and rod connections of various types.

In knuckle joint one end of the rod is made into an eye and end of the other is formed

into a fork with an eye in each of the fork leg. The knuckle pin passes through both the eye

hole and fork holes and may be secured by means of a collar and taper pin or split pin. The

knuckle pin may be prevented from rotating in the fork by means of a small stop, pin, peg or

snug. In order to get a better quality of joint, the sides of the fork and eye are machined , the

hole is accurately drilled and pin turned the material used for the joint may be steel or

wrought iron.

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CHAPTER-2

GEOMENTRICAL MODELLING

A knuckle joint is a pin joint used to fasten two circular rods. In this joint, in this joint, one

end of the rod is formed into an eye end the other into a fork(double eye). For making the

joint the eye end of the rod is aligned into the fork end of the other end then the pin is

inserted through the holes and held in position by means of a collar and a taper pin once the

joint is made, the rods are free to swivel about the cylindrical pin.

Knuckle joint are used in suspension links, air brake arrangement of locomotive, etc.

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CHAPTER-3

INTRODUCTION TO CATIA

CATIA V5R20: CATIA abbreviates computer aided three dimensional Interactive Application. As a new user of this softer package, you will be joining hands with thousands of users of this high end CAD/CAM/CAE tool world-wide. You can upgrade your designing skills with latest release.

CAITA V5, developed by Dassault systems. France is completely re-engineered next generation family of CAD/CAM/CAE software solutions for product life cycle management. CATIA V5 delivers innovative technologies for max Productivity and creativity from concept to the final product. CATIA V5 reduces the learning curve as it allows the flexibility and parametric designs.

CATIA V5 Provides three basic flat forms: P1, P2, P3.

P1 is for small and medium sized process oriented companies.

P2 is for the advanced design engineering companies that require product.

P3 is for the high –end design application and is basically automotive and aerospace industry. Where high quality surface is used for designing.

The subject of the interpretability offered by CATIA includes receiving legacy data from other system and even between its own product data management modules. The real benefit is that links remain associative.

CATIA V5 serves the basic design tasks by providing different work benches. A work bench is defined as “A specified environment consisting of asset of tools, which allows the user to perform specific design tasks in a particular area” the basic work benches are part design, wire frame and surface design work bench, assembly work bench & drafting.

SYSTEM REQUIREMENTS:

The system requirements of CATIA V5 are:

System unit: An Intel Pentium III or Pentium IV based work station running Microsoft 2000 professional edition or XP edition.

Memory: 256MB RAM is used for all application.

512 MB RAM is used for DMU application.

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Disc drive: 4GB Disc drive space [min.recomended]

Internal/External drives: A CD-ROM drive is required for the program installation.

Display: A graphic colour display compatible with selected plat from with min.recomended 1711.

Graphics adaptor: A graphic adaptor with a 3d open GL accelerator is required with min. resolution of 1024*768 for MS –WINDOWS and 1280*1024 for UNIX WORK stations.

Getting started with CATIA V5 R20:

Install CATIA V5 R20 on your system and then start it by double checking on the short cut icon of CATIA V5 R20 on the desktop.

After the system has loaded all the required files to start CATIA V5 R20. A new product file with default name of product1 will start automatically.

Specification Tree:

The specific tree keeps a track of all operations that carried out on the part .it will app-ears when you start a new file. Under the part design.

Part 1: XY- plane, YZ- plane, ZX-plane- Part body. The segment to become vertical.

Assembly constraints: The constraints in the assembly design work bench are the logical operations performed to restrict the degree of freedom of the component to define its precise location and position w.r.to the order component to the assembly (the constraints in the work bench are)

Co-incidence constraints: this constraint is used to force two selected entities to coincide with each other. The selected entities to coincide with each other. The selected entities can be central axes of circular components two adjacent or opposite force or two adjacent planes.

Contact constraints: This constraint between each off is used to force to create a contact between each other.

Off set constraint: This constraint is used to place two different selected faces planes or central axis at a distance with reference to each other.

Angle constraint: This constraint is used to place two selected entities at an angle with reference to each other. The entities can be central axes of circular components two faces, two planes, or a combination of the axis and faces, planes and face or axis and plane.

Fix component: This constraint fixes the position to the selected component in the 3D space.

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Fix together: This constraint fixes the position of two different selected part with respect to each other.

Quick constraint: the quick constraint tool is used to apply the most appropriate constraint to the elements in the current selection set. You can set the priority in which CATIA V5 will perform the constraint selection.

Part body: This constraint fixes the position of two default body in the part design work bench. All solid related features such as a pad, pocket shaft and so on are placed inside it. Other bodies that will be inserted under the part design work bench will be named as part2, part3 and so on.

Geometrical set: The geometrical set is defined as a body that includes the newly created planes, surface wire frames, elements and reference element.

Wire frame: The wire frame construction element aid in creating surface they generally consists of points, lines and axes and are used as substitutes to entities drawn in sketcher work bench.

Surface: Surface is geometric feature which have no thickness. They are used to create complex shapes that are difficult to make using the solid feature after creating a surface you can assign a thickness to it to convert it into solid body.

Features: A feature is defined as a basic building block of a solid model. The combination of various feature results in a completed model. In the part design work bench of CATIA V5 the features are of the following 4types.

1. Sketch- based features

2. Dress- up Features

3. Transformation features

4. Surface- Based features.

Reframe on: Sometimes a feature, body or a sketch may not be visible space in the geometry area. This option is used to view the particular section in the available display space.

Centre graph: This option brings the selected feature body or sketch in the specification tree to the middle left position of the geometry.

Tool bar: CATIA V5 offers a user friendly design environment by providing specific tool bars to each workbench Therefore it is important that you get acquainted with the various standard tool bars and buttons that appear in the work bench of CATIA V5.

Standard tool bar: The tool bar is common to all work bench of CATIA V5. The buttons in the toolbar are used to start a new file, open an existing file, save file and to print the current

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document. These buttons are also used to and place the selection on a temporary clipboard, copy a selection, paste the content from clipboard to selected locations undo, redo and involve the help topics, the help button called what is this? Provides help on the tool bar.

Standard tool bar:

Cut - what’s this? Copy - Quick print Paste – Save Undo - Open Redo – New.

Status Bar: The status bar which appears at the button of the CATIA V5 window comprises of 3 areas

Current information or Dialogue boxPower input filed barDialogue box display button.

Current information or Dialogue box: This displays the current information about the selected feature or current tool.

Power Input Filed bar: The power in put field bar lets you involve the command and enter the data or value that can be directly associated with the feature.

Note: In case an in correct command is entered in the power input field bar a power input message dialog box appears indicating the unknown command or syntax error choose the ok button from this dialog box to launch any command using the power input field box the general syntax of command is C:< name of the command> for example to start a new file enter C: New

Dialog box display button: Choosing the dialog box display button will turn on and turn off the display of the current dialog box.

User information package button: Choosing this button will open a window with a default link that is C:\program files\Dassault system\B14\Intel-a\resource\galaxy\default .htm .you can learn more about PLM latest news from dassault system technical support and so on using the link on this page you need an internet connection to access these pages.

Part design work bench tool bars: You can involve the part design work bench by choosing the new button from the standard tool and selecting part from the new dialog box. Alternatively you can choose start> mechanical design> part design from the menu. Tool bars in the part design work bench are discussed.

View tool bar: The button in the view tool bar are used for manipulating the view of the model using the tools such as pan, zoom, normal viewing about planar surface face or plane, defining a render style and so on. The view tool bar is available in all the work benches.

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View tool bar commands:

Zoom out - Normal viewZoom in - Create multi-viewRotate - Isometric viewPan - Shading with edgeFit all in - Hide/showFly mode - Swap visible space.

Select tool bar: The select tool is involved from the select tool bar to select a particular object or sketch when you choose the select box it prompts you to select an object or a tool. By default the select tool remain active, until another tool or object is selected.

Sketcher tool bar: The Sketcher button in the sketcher tool bar is used to involve it from the main menu bar by choosing.

Start >mechanical design >sketcher.

After choosing the sketcher button select a plane or a planar force to involve the profile tool bar are used to draw the sketcher. It is one of the most important tool bar in the sketcher work bench.

Profile tool bar: The tools in the profile tool bar are used to draw the sketcher. It is one of the most important tool bar in the sketcher work bench.

Profile tool bar commands:

Spline Profile Circle Ellipse Rectangle Line Axis Point by clicking

Constraint tool bar: The tools in the constraint tool bar are used to apply constraint to the geometric entities and assign dimensions to the draw a sketch you can make a sketch fully defined using tool in the tool bar. A fully defined is known as an ISO-constraint sketch

Button in constraint tool bar: Constraint - Fix together Constraint defined in dialog box Animated constraint -Edit – multi- constraint

Operation tool bar: The tools in the operation tool bar are used to edit the drawn sketcher. Button in the operation tool bar:

Chamfer – mirror – corner Trim – project 3D element.

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Sketch tool bar: The tools in this sketch tool bar are used to set the sketcher settings such as setting the snap swishing the standard and construction elements and soon.

The button in sketch tool bar:

Construction/ standard elements Snap to point Grid Geometrical constraint. Dimensional constraint.

Once the basic sketch is complete you need to convert it into a feature. Choose the exit work bench button from the work bench tool bar and switch back to the part design work bench. Sketch based featured tool bars are used to convert a sketch drawn in the sketcher work bench into a feature.

The button in the sketch based feature tool bar:

Hole Pocket Slot Remove multi selection solid Groove Pad Solid combine Shaft Rib Multi selection solid.

Dress up features: The tools in the dress-up feature tool bar used to apply the dress-up features such as fillet, chamfer, and shell and so on:

The button in the dress up features tool bar:

Draft angle Shell Chamfer Thickness Remove face Edge fillet Thread/tap

Measure tool bar: The tools in the measure tool bar are used to measure a single item the distance b/w two geometric on calculate the mass properties of the object.

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The button in the measure tool bar:

Measure betweenMeasure itemMeasure inertia.

Transformation feature tool bar: The tools in the transformation feature tool bar are used to (surface based operation) apply the transformation features to the part such as moving mirror, pattern and so on

The button in the transformation feature tool bar is:

MirrorRectangular patternTranslationScaling

Surface –Based feature tool bar: The tools in the surface based feature tool bars are used to perform surface based operations on part bodies or to convert a surface body into a solid body.

surface Thick Close feature Split Sew surface.

Apply material tool bar: The tool in the apply material tool bar is used to assign a material to the part body.

Wire frame and surface design work bench tool bar: You can involve the wire frame & surface design work bench tool bar from maintenance bar by choosing start> mechanical design > wire frame and surface design.

Surface tool bar: The tools in the surface tool bar are used to create surface

Surface Offset Blend Sphere Sweep Revolve Fill Extrude

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Multi selection surface.

Operation tool bar: The tools in the operation tool bar are used for surface editing operations.

The button I the operation tool bar:

Split Translate Join Extra polate Boundary

Wire frame tool bar: The tools in the wire frame tool bars are used to create 2D or 3D curves using points, lines and splines. User defined planes can also be created by choosing the plane button.

The buttons in the wire frame tool bar are:

Plane Inter section Projection Line Circle Point Spline

Assembly design work bench tool bar: You can involve the assembly design work bench by choosing the button from the standard tool bar and selecting product from the new dialog box. Alternatively choose Start >Mechanical design > Assembly design from the menu bar. The tool bars in the assembly design work bench are discussed next.

Product structure tools tool bar: The tools in the product structure tool bar are used to insert an existing part or assembly in the current product file. You can also create anew assembly or part inside the product file using the tools in this tool bar.

The button in the product structure tools tool bar:

Existing component with positioning Existing component Part Part Product Component Graph tree- reordering

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Generate numbering Selective load Manage representation Fast multi instantiation

Constraint tool bar: The constraint tool bar is used to apply constraint to the component of the assembly to restrict its degree of freedom w.r. to the surrounding.

The buttons in the constraint tool bar are:

Fix component Angle constraint Off set constraint Contact constraint Change constraint Coincide constraint Quick constraint Fix together Flexible rigid sub- assembly Reuse pattern.

Move tool bar: The tools required to perform operations such as moving and snapping the parts or exploding an assembly in the assembly design work bench are available in the move tool bar.

The button in the move tool bar are:

Snap Explode Manipulation Stop manipulation.

Space analysis tool bar: The tools in the space analysis tool bar are used to check any interference and clash in the assembly create the section of the assembly and perform the distance analysis.

The button in the space analysis tool bar is:

Clash distance and Band Sectioning Analysis

Drafting work bench tool bar: To involve the drafting work bench choose the new button from the standard tool bar and select the drawing from the new drawing dialog box.

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Alternatively this work bench can involve by choosing Start> Mechanical Design > Drafting from the menu bar.

Drawing tool bar: The tools in the drawing tool bar are used to insert anew sheet. Create a new view and so on.

Button in the drawing tool bar is:

New sheet Instantiate 2D Component New view

View tool bar: The tools in the view tool bar are used to generate orthographic section detail or clipped views for a solid part or assembly.

Buttons in the view tools bar are:

Detail view Offset section view Front view Clipping view Broken view View creation wizard.

Sl.No HOT KEYS FUNCTION

1. CTRL+Z Undo

2. CTRL+Y Repeat

3. CTRL+S Saves repeat current document

4. ALT+ENTER Involves the properties tool

5. CTRL+F Involves the search tool

6. CTRL+U Involves the update tool

7. SHIFT+F2 Involves the specification over view tool

8. F3 Toggles the display of the specification tree

9. SHIFT+F1 Involves what’s this? Tool

10. F1 Involves the CATIA V5 help tool

11. CTRL+D Involves the fast multi-instantiations tool in the assembly

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design work bench.

12. CTRL+E Involves the define multi-instantiations tool in the assembly design work bench.

- - Distance - Fix - Symmetry - Length- - Coincidence - Mid-point - Angle - concentricity- - vertical - Radius/Diameter - Tangency - Equidistant

point- - Semi major

axis- Semi minor axis Sketcher tool bar:

Polygon trap Intersecting trap Selection trap Select Point stroke

selection Outside trap

selection Intersecting outside

trap selection.

Drawing lines with a symmetrical extension:

Bi-tangent line Bisecting line Lines Infinite line Line normal to curve.

Drawing Rectangles:

Cylindrical elongated hole

Elongated hole Parallelogram Oriented rectangle Rectangle Key hole profile Hexagon Cantered rectangle Cantered

parallelogram

- Perpendicular

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Drawing Circles: Circle using co-

ordinates Three point circles Circle Tri-tangent Circle Three point arc Three point are with

starting limits Arc

Drawing profile:

Lines Tangent arc Three point arc

Drawing display tools:

Zoom in Zoom out Rotate Pan Fit all in Fly mode Normal view Create multi-view Isometric view Shading with edges Hide /show Swap visible space.

Drawing an ellipse:

Parabola by focus Hyperbola by focus Ellipse Conic

Drawing splines:

Spline Connect

Connecting two elements by

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arc or spline:

Continuity in point Continuity in

tangency Continuity in

curvature Connect with a spline Connect with an arc

Trimming UN wanted sketched element:

Quick trim Close Trim Break Complement

Mirroring sketched element:

Translate Rotate Symmetry Scale Mirror Off set

Offsetting sketched Elements:

Tangent propagation Point propagation No propagation Both side offset.

Constraining sketches:

Constraint defined in dialog box

Constraint Fix together Edit multi-constraint Animate constraints.

- Apply additional constraints to the

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sketch:ParallelismApplying dimensional constraints: Constraint Contant constraint

Creating base feature by extruding:

Drafted filled pad Multi pad Pad

Modifying the view orientation:

Left view Isometric view Bottom view Rear view Right view Named view Front view Top view

Display modes of the model:

Shading with edges without smooth edges Shading with edges shading SHD Shading with edges and hidden edges Shading with materials Wire frame Customise view parameter.

Reference elements:

Point Plane Line

Creating Fillets:

Variable radius fillet Face-face fillet Edge fillet Tri-tangent fillet

Measuring element:

Measure Item

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Measure between Measure Inertia.

Translating Bodies:

Rotation Translation Symmetry.

Components of a knuckle joint:

Fork end Eye end Knuckle pin Collar Taper pin

Fig.3.1 FORK END

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Fig.3.2 EYE END

Fig.3.3 KNUCKLE PIN

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Fig.3.4 COLLAR

Fig.3.5 TAPER PIN

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Fig. KNUCKLE JOINT

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CHAPTER-4

MATERIALS USED FOR KNUCKLE JOINT

The knuckle joints which are used in the industries are generally made by the combination of cast iron and stainless steel. Rapid growth of technology in recent decades led to reduction of cost and weight of the materials as a result accidents have reduced and safety has increased. knuckle joint may be cast or fabricated or forged. Teflon can also replaced with the cast iron. Recent researches have proved that if we use composite material instead of cast iron, there will be many advantages such as making of knuckle joint is easy, having maximum safety and eco-friendly.

A knuckle joint may be failed on the following three modes:

1.shear failure of pin(single shear)

2.crushing of pin against rod.

3.tensile failure of flat end bar.

The failure mechanism of knuckle joint has been studied by several investigators.

Jones has reported that shear failure due to tensional loading is the normal failure

Mechanism in many engineering components. pantazopolouset have studied the failure

of a knuckle joint of a universal coupling system. It was mentioned that torsional

overload of a knuckle joint is the major cause of failure. However in many cases it

was reported that wear of material due to severe friction leading to delimitation wear.

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chapter– 5

ADVNTAGES AND DISADVANTAGES OF

A KNUCKLE JOINT

ADVANTAGES:

Knuckle joint can withstand large tensile loads. It has good mechanical rigidity. It is easy to manufacture and setup. It can be easily assembled and dismantled. Design is simple and easy. High repeating accuracy even with varying material thickness and tensile strengths. Reduced impact shock and high system rigidity. Long tool life.

DISADVANTAGES:

The joint cannot withstand large compressive loads. It permits angular movement in only one plane. It is not as flexible as universal joint.

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CHAPTER-6

APPLICATIONS OF A KNUCKLE JOINT

Knuckle joints are mainly used to connect two coaches of a train. Knuckle joints are used in wind shield wipers in automobiles. In automotive engine small end of connecting rod is connected to piston

By means of a knuckle joint. Knuckle joints are used in the robotic arms. Knuckle joints are used in the links of the cycle chains. Knuckle joints are used in the cranes. Knuckle joints are used in the earth movers. Knuckle joints are used in the chain straps.

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Conclusion:

The knuckle joint is more reliable in the case of tensile loads, when compared to the other joints. By replacing cast iron with the composite material or Teflon the strength, reliability, safety are optimised. Due to the automation the use of knuckle joints in industries is increasing day by day.

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