Spring

Present design deals with the power transmission from one place to another. There are different mechanisms by which one can transmit the power, liker gear system, crank chain mechanism, spring etc.

A spring is an elastic body, whose expand in size when load applied and regain its original shape when removed. It absorbs automobile vibrations, shocks and loads by springing action and to some extend by damping functions. It absorbs energy in the form of potential energy. Springs capacity to absorb and store more strain energy makes the suspension system more comfortable. Leaf spring is the simplest form of spring used in the suspension system of vehicle. These springs are also known as flat, laminated or carriage spring. Most widely used leaf spring type is semi-elliptic in heavy and light automobile vehicles. The multi leaf spring comprises of various steps called blades while mono leaf spring is of only one step. Number of steps increases the spring absorbing capability. For heavy vehicles multi leaf spring are used while light vehicle mono leaf spring can be used.

Springs initially given a camber so they will have a tendency to bend under loading condition. The leaf spring works under two hypothesis uniform strength and uniform width. The master leaf spring is the longest and has eyes at its end while remaining steps of spring are called graduated leaves.

A gear transmits power from one shaft to another. It is a rotating machine which has teeth on its periphery. Teeth on meshing gears should have the same shaper for proper transmission of motion or power. At least two gears are required for transfer of motion from one shaft to another, more than two gears produces a gear train which has wide amount of applications in the automobile industry. If one gear is smaller it will rotate faster compared to the larger gear. One gear is termed as driver gear while second gear is termed as driven gear.

Figure below shows the power transmission mechanism.

Above figure illustrates the type of motion transmission. In this mechanism two axial has been used to hold the power transmission plate in their respective positions. While two connecting plates has been utilized to connect them with the connecting angle with the help of connecting shaft.

Above figure shows the top view of the power mechanism generated in the present work.

Above figure shows the front view of the power transmission mechanism produced in the present work. From the front view one can easily visualise all the parts of the power transmission mechanism.

Gear

Above figures shows the 2D view of the different parts of the power transmission system. Figure 1-a represents the connecting angle while figure 1-b represents the connecting shaft and connecting angle together. Figure 1-c represents the connecting plate and power transmission plate together while figure 1-d represents the top portion of the assembly which includes axial holder, power transmission plate and connecting plate.

Below figure shows the right view of the power transmission assembly. In this assembly axial holder will remain on their while all other parts will rotate at an angle. The bottom power transmission plate will rotate on their axis; due to the motion of power transmission plate bottom connecting plate will also rotate, same will happen with the upper part of the body which will also rotate. This full rotation will give a rotatory motion to the assembly. This rotatory motion either is circular or spherical shape which will depends upon the angle developed. This type of motion can be applied to the applications where rotation of any device at any angle is required.

Shokrieh and Rezaei (2003) conducted optimization of spring while Pateriya and Khan (2015) studied dynamic characteristics. Different materials have been used considering similar boundary condition for finding the best suitable material. Pozhilarasu and Pillai (2013) analysed conventional steel and composite material. They also utilized GFRP (glass fibre reinforced polymer) in their analysis. Aishwarya et al (2014) conducted vibration analysis of assembly made of composite material.

Kumar et al (2014) conducted optimization analysis of material for large weight vehicles. They used ANSYS to conduct their study and compared their results between composite material and conventional material. Anuraag and Sivaram (2012) targeted their analysis towards shock analysis and dynamic analysis of spring made of composite materials having different layers. They modelled their leaf spring using Unigraphics software NX7.5. They sued ANSYS to analyse their study. They have done static, dynamic and shock analysis. For analysing the results they have used five layered and two layered composite leaf spring. They noticed maximum displacement in the two layered leaf spring compared to five layered 101.5mm to 83.23mm. They found more compressive stress in case of vehicles with more layers compared to vehicles with fewer layers. They found that shock first increases than decreases for fewer layers vehicle, and also concluded that shock increases with increment in the time. While for vehicles having larger layers deflection first decreases than increases with increment in the time.

Top View

Mahdi et al (2006) and Kumar & Teja (2012) analysed the suspension system of the vehicles having elliptic spring. They conducted different sets of experimentation to analysed the behaviour of spring, they also conducted the numerical analysis for same sets of variable and compared them, found that results matches well with the experimental results. They determined that design of experiments helps in achieving the best results. Amrute et al (2013) and AI-Qureshi (2001) conducted study on composite material leaf spring. They considered a composite spring and analysed its behaviour under different sets of parameters. Rupesh et al (2015) and Zhang et al (2014) conducted Analysis on Performance of Leaf Spring Rotary Engine. They simulated a leaf spring rotary engine which was different on the basis of rotor structure.

Durus et al (2015) conducted fatigue life prediction of z type leaf spring and new approach to verification method. They studied the different loading condition. They conducted the results when fracture reached and to take process effect they framed an S-N curve. A finite element tool has also been used by them to perform the study and they found that FE tool generates the good results. Fuentes et al (2009) conducted premature fracture in automobile leaf springs which has been used in Venezuelan buses. They conducted failure analysis and fracture analysis on the Venezuelan bus. They also conducted Chemical analysis, macroscopic inspection, metallographic analysis and hardness test.

Load required to create a unit deflection is called spring stiffness.

Stiffness of the spring is in Newton/meter (N/m)

Load in Newton

Deflection in meter

Below a flow layout of the manufacturing of the parts to be created, first the raw materials will be selected after that cutting of the material will be done as per the required shape or size, than different test and operations will be performed on the material as per the requirements.

Finite element analysis of the above assembly can be done to analyse the regions whwre maximum amount of deflection and stress are generating. FEM is a great tool as it helps in understanding the model developed accurately before going for actual production.

This can be done with the help of software available in the market like Abaqus or ANSYS. Geometry created in the Autodesk inventor can be imported in these tools for further analysis.

Two different materials have been considered in the present study. Conventional steel and E-glass/Epoxy has been used as an alternative material. Weight reduction by using E-glass/Epoxy can also be studied in the present work.

Front View

Mechanical properties and composition of conventional steel (EN47 steel) have been shown in table 1 and 2. While E-glass/Epoxy mechanical properties are represented in table 3.

Table 1 Steel (EN47) mechanical properties

Table 2 Chemical composition of steel (EN47)

Table 3 E-glass/Epoxy material properties

From the tables above it can be noticed that the density of the e-glass material is very less compared to the conventional steel material. If we compare the same geometry for two different materials considered in the study, this will give that the power transmission assembly made of E-glass material weight less compared to the power transmission assembly made of conventional steel.

References

Aishwarya A.L., Kumar, A. E. & Murthy, B.V., (2014), Free vibration analysis of composite leaf springs, International Journal of Research in Mechanical Engineering & Technology, 4(1), 95-97.

Ai-Qureshi, H.A., (2001), Automobile Leaf Spring from Composite Materials, Journal of Materials Processing Technology, 118(1-3), 58-61.

Amrute A. V., Karlus E. N. & Rathore R. K., (2013), Design and Assessment of Multi Leaf Spring, International Journal of Research in Aeronautical and Mechanical Engineering, 1(7), 115-124.

Durus M., Kirkayak L., Ceyhan A. & Kozan K, (2015), Fatigue Life Prediction of Z type Leaf Spring and new approach to verification method, Procedia Engineering, 101, 143-150.

Fuentes, J.J., Aguilar, H.J., Rodr?´guez J.A. & Herrera, E.J., (2009), Premature Fracture in Automobile Leaf Springs which has been used in Venezuelan Buses, Engineering Failure Analysis, 16(2), 648-655.

Kalwaghe R. N. & Sontakke K. R., (2015), Design and Analysis of Composite Leaf Spring by using FEA and ANSYS, International Journal of Scientific Engineering and Research, 3(5), 74-77.

Kumar A. T. N. V., Rao E. V. & Krishna G. S. V., (2014), Design and Material Optimization of Heavy Vehicle Leaf Spring, International Journal of Research in Mechanical Engineering & Technology, 4(1), 80-88.

Kumar S. Y. N. V. & Teja M. V., (2012), Design and Analysis of Composite Leaf Spring, International Journal of Mechanical and Industrial Engineering, 2(1), 97-100.

Mahdi E., Alkoles O.M.S., Hamouda A.M.S., Sahari B.B., Yonus R., & Goudah G., (2006), Light composite elliptic springs for vehicle suspension, Composite Structures, 75(1-4),  24–28.

Patnaik M., Yadav N. & Dewangan R., (2012), Study of a Parabolic Leaf Spring by Finite Element Method & Design of Experiments, International Journal of Modern Engineering Research, 2(4), 1920-1922.

Pateriya, A, & Khan, M., (2015), Structural and thermal analysis of spring loaded safety valve using FEM, International Journal of Mechanical Engineering and Robotics Research, 4(1), 430-434.

Pozhilarasu V. & Pillai, T. P., (2013), Performance analysis of steel leaf spring with composite leaf spring and fabrication of composite leaf spring, International Journal of Engineering Research and Science & Technology, 2(3), 102-109.

Saianuraag K. A. & Sivaram B. V., (2012), Comparison of Static, Dynamic & Shock Analysis for Two & Five Layered Composite Leaf Spring, Journal of Engineering Research and Applications, 2(5), 692-697.

Saini P., Goel A., & Kumar D., (2013), Design and analysis of composite leaf spring for light vehicles, International Journal of Innovative Research in Science, Engineering and Technology, 2(5), 1-10.

Shokrieh, M. M. & Rezaei, D., (2003), Analysis and optimization of a composite leaf spring, Composite Structures, 60, 317–325.

Zhang Y., Zou Z-X, Yuan C-H & Wang D-J, (2014), Analysis on Performance of Leaf Spring Rotary Engine, Energy Procedia, 61, 984-989.