Pdf design, analysis and optimization of leaf spring. The results showed that a spring width decreases hyperbolically. They are used as cantilever springs fixed at one end, or as simple beams fixed at both ends. Springs based on the principle of long slander beams of rectangular section subjected to bending. Leaf spring design and engineering strength of materials. When the leaf spring deflects, the upper side of each leaf tips slides or rubs against the lower side of the leaf deflects. Abstract this paper explains the design of new type of leaf spring which has an integrated damper system. With the theory of leaf spring and by hypermesh software following result for structure analysis result is concluded. Valve spring is a critical component for any engines performance. The leaves are use usually given an initial curvature or cambered so that they will tend to straighten under the load. In this project work, a heterogeneous model leaf spring. Design and analysis of leaf spring for solar vehicle proceedings of 105th ththe iier international conference, bangkok, thailand, 5 6th june 2017 103 ii. In this case, imagine your audience to consist of one of your classmates who had to miss this weeks lab.
In this paper we describe design and analysis of composite leaf spring. The leaf spring is based upon the theory of a beam of uniform strength. Gfrp with similar mechanical and geometrical properties as the multileaf spring, was designed 4. Invention of leaf spring leaf spring was invented by obadiah elliot of london in 18th century. Nowadays, cad and fea tools are used extensively in the industry for the design of leaf spring. It is built up of a number of plates known as leaves. Design and numerical investigation of static and dynamic. Following are the objectives of a spring when used as a machine member. The thickness and width of the front leaf springs for optimum design are 8 mm and 50 mm. Design, analysis and optimization of leaf spring dhiraj k. The chassis supports the two ends and middle of the leaf spring is connected to the axle. Usually of rectangular shape, sometimes springs thicker in the middle and at the end of the leaf are used. This stress evaluation with load deflection test is challenging task, in validation dynamic and static friction will play key role in the suspension system. So, in this work rigid joint of agricultural trolley is to be replaced with flexible joint v shape spring for suspension system.
Design of leaf springs mechanical engineering notes edurev. Design procedure of the leaf spring in design procedure of leaf springs, firstly, the weight. Leaf springs are all but dead as a technology in the car world. Design of leaf springs design aspects design of springs machine design i duration. The above mentioned studies provide theoretical guidance for the. A spring with squared and ground ends compressed btbetween.
Leaf springs are subdivided into longitudinal and transverse leaf springs. He simply piled one steel plate on top of another, pinned them together and shackled each end to a carriage, it was the first ever leaf spring. Leaf spring design guidelines explained here is the simplest version of the whole leaf spring design procedure. From the theoretical and the ansys, the allowable design stress is found. The advantage of leaf spring over helical spring is that the ends of the spring may be guided along a definite path as it deflects to act as a structural member in addition to energy absorbing device. In new light commercial vehicle development, engine is mounted at rear to have low engine noise and vibration inside cabin. Substitution of h in the stress equation above will yield the value of plate width b. The objective is to compare the stresses and weight saving of composite leaf spring with that of steel leaf spring. Design of a modified leaf spring with an integrated damping system for added comfort and longer life sean dsilva 1, sumit jain 2 1, 2 department of mechanical engineering, rajiv gandhi institute of technology, mumbai, india. Design and experimental analysis of leaf spring using. The design of the leaf spring on ansys is shown in figure no. The benefit of leaf spring over helical spring is that the ends of the spring may be leaded along a definite path as it deflects to act as a structural. The dimensions of an existing conventional steel leaf spring of a light design calculations. Jeevan kumar 39 leaf springs are unique kind of springs used in abstract automobile suspension systems.
Manual on design and application of leaf springs hs788 a revised guide to the design of both multi leaf and single leaf tapered springs, this manual includes nomenclature and specifications for spring design elements such as. Vertical leaf spring rate and strain data were studied. It was then fabricated handlayup technique and tested. The main point of the analysis study is to improve the quality of this design for a leaf spring with a longer life, and achieve a big reduction in vibration forces.
Leaf springs are used for rear suspensions on cars and many light trucks. China abstract a leaf spring bender geometry for watercooled double. As the leaf spring is compressed, the steel leaves bend acting as. A flat spring is much more likely to twist as is a spring over design. Leaf springs are mainly used in suspension systems to absorb shock loads in automobiles like light motor vehicles, heavy duty trucks and in rail systems 1. Leaves are made up of laminated strips of curves steel. It is important when designing springs to adhere to proper procedures and design considerations. Leaf spring design guidelines laminated leaf spring. Reducing weight while increasing or maintaining strength of products is getting to be highly important research issue in this modern world. At the same time there is a need of high load carrying rear suspension to suit market requirement. Consider, allowable bending stress for the spring material. Longitudinal leaf springs are used only on rigid axles, more commonly on commercial vehicles and trailers.
Design of a leaf spring bender for double laue crystal. A variable rate can be accomplished with a leaf spring suspension by providing contacts on the mount that effectively. In spite of the widespread theoretical static analysis of leaf spring, there is lack of experimental fidelity in the ensuing models. Single leaf steel springs, called mono leaf, are used on some vehicles. Nonuniform leaf springs with geometric nonlinearity. The abovementioned studies provide theoretical guidance for the. Design and analyze helical compression springs, including compatibility with allowable stresses.
A leaf spring takes the form of a slender arcshaped length of spring steel of rectangular crosssection. Belleville washers disk springs considerations prior to the spring design process. Therefore, once the design parameters, given on the left side of the above equation, are fixed the value of plate thickness, h can be calculated. Composite materials are one of the material families which are attracting researchers and being solutions of. The leaf spring placed perpendicularly to support the weight of vehicle.
Optimal design of automobile leaf spring using finite. Thus the leaf springs may carry lateral loads, brake torque, driving torque etc. In the most common configuration, the center of the arc provides location for the axle, while loops formed at either end provide for attaching to the vehicle chassis. A single or mono leaf spring is usually tapered to produce a variable spring rate. Main objective of this study was the behaviour of parabolic leaf spring, design of experiment has been implemented. In this paper complete design of leaf spring rear suspension for rear engine is discussed. The basic principle of leaf spring design and assembly are moderately simple the number of leaves in an spring is relies on the weight conveying limit of a vehicle most heavy duty vehicle today use two pairs of leaf spring per axle. The leaf spring design is based upon the theory of beams of uniform strength.
Optimal design of automobile leaf spring using finite element. Multileaf spring and hotchkiss suspension cae simulation. Computer algorithm using clanguage has been used for the design of constant crosssection leaf spring. The design process of the leaf spring is another aspect that can be optimized in order to improve the load carrying capacity and fatigue life of the spring. Leaf springs absorb the vehicle vibrations, shocks and bump loads. A spring with plain ends that are squared or closed is obtained by deforming the ends to a zerodegree helix angle. This was the centerbolted leaf spring supported on rollers at both eyes.
Construction of leaf spring a leaf spring commonly used in automobiles is of semielliptical form as shown in fig. Pdf leaf springs design, calculation and testing requirements. Pdf design, analysis and optimization of leaf spring abhijeet. Consider, allowable bending stress for the spring material as 350 mpa and e2 10 5 mpa. Fatigue life prediction of z type leaf spring and new. Fem analysis of leaf spring for different composite. Theory it is essential that the theory section be written for the particular audience for which the report is intended. Deflections and stresses for nonlinear bending are discussed and compared with those of a traditional leaf spring by rajendran and vijayarangan 1. Static analysis of model of leaf spring is performed using ansys 11. The testing principle involves subjecting a scaled down sprung tank to the. Comparative theoretical design of leaf spring and vshape. There are many factors that go into reducing axlewrap. Cushioning, absorbing, or controlling of energy due to shock and vibration. Spring design objectives identify, describe, and understand principles of several types of springs including helical compression springs, helical extension springs, torsion tubes, and leaf spring systems.
Yang 1 1shanghai institute of applied physics, shanghai 201800, p. Extension springs extension springs are similar to compression springs within the body of the spring. Pdf design development and performance analysis of leaf. Preferring composite materials is very costly even though they are far better than metals, so, it is evident to develop an economical, maintenance friendly design for the leaf spring system. For leaf springs, the lightweight design of trucks is mainly reflected. To apply tensile loads, hooks are needed at the ends of the springs. Based on the linear theories of curve beams, the first derivative matrix equation of the combination statusvector is deduced, which discusses the difficulty of. China 2 university of chinese academy of sciences, beijing 49, p. Moreover, design verifi cation methodology of conventional leaf springs is directly related with suspension travel because there is a direct relation between displacement and applied. A spring can is used for multiple purposes and functions in different devices, some of them are listed below. In this paper complete design of leaf spring rear suspension for rear engine is. Fatigue life prediction of z type leaf spring and new approach to.
International journal of applied engineering research issn 09734562 volume 14, number 10, 2019 special issue. Assume permissible shear stress for spring material as 420 mpa andspring index as 5. In order to have an idea of working principle of a leaf spring, let us think of the diving board in a swimming pool. Springs should always be both squared and ground for important applications, because a better transfer of the load is obtained.
Venkatesan2 pg scholar, computer aided design,university college of engineering,nagercoil. The rotation of the axle housing twists the leaf springs into an s shape. Spring design for target load and stiffness is also completed. The stress induced in the cglassepoxy composite leaf spring is 64% less than that of the steel spring nearly and the. The suspension leaf spring is one of the potential items for weight reduction in automobiles unsprung weight. Design a leaf spring to carry a load of 3400n and placed over a span of 800 mm.
867 368 1459 485 723 35 339 1361 1300 1493 843 71 1478 30 455 935 415 365 833 510 1233 1024 956 1140 790 480 708 253 528 1513 280 360 525 1485 886 612 849 32 354 1015 488 994 150 871 1411 37 1233 1287 692