Published on September 18, 2011
Slide 1: Submitted to; A Seminar On “ Automobile suspension system” Submitted by:- NAME: GUJARWAD RAMDAS GANPAT Under the guidance of Mr.Khade S.G. Submitted to:- Dept. of Mech. Engg. Indira Institute of Technology Vishnupuri , Nanded contents: contents INTRODUCTION SOURCES OF VIBRATION NEED OF SUSPESION SYSTEM FUNCTION OF SUSPESION SYSTEM CLASSIFICATION OF SUSPESION SYSTEM CONCLUSION REFRENCES What is suspension system: What is suspension system Suspension is the term given to the system of springs, shock absorbers and linkages that connects a vehicle to its wheels. It is protect the vehicle from vibrations stresses and from rolling etc. The element which protect the vehicle and passengers from this causes and hence the element or devices is called as suspension system. SOURCES OF VIBRATION: SOURCES OF VIBRATION Road imperfection. Vibration in torque. Pitching of body Centrifugal force during cornering which cause rolling and slip in tyre. NEED OF SUSPENSION SYSTEM: NEED OF SUSPENSION SYSTEM In order to provide comfortable ride to the passengers . Avoid additional stresses in the vehicle frame. For maintaining good condition of the vehicle. FUNCTIONS SUSPENSION SYSTEM: FUNCTIONS SUSPENSION SYSTEM To acts as a safeguard for the for the occupants against road shocks and provide comfort ride. To preserve the stability of the vehicle in rolling, pitching, while in motion. To keep the body perfectly in level while travelling over the uneven road. types suspension systems: types suspension systems Conventional suspension system Independent suspension system Air suspension system Hydro elastic suspension system Conventional suspension system: Conventional suspension system Two wheels are mounted on either side of the rigid axle When one wheel encounters the bump, both the wheel do not execute parallel up and down motion. Rear driving wheels mounted on live axle suspended by laminated leaf springs and shock absorbers It is used in truck, buses, jeep etc. Independent suspension system: Independent suspension system The independent system in which there is no rigid axel beam and each wheel is free to move vertically without any reaction on the other wheel. It again classified:- Independent front suspension 1)Mac-pherson strut type 2)Wishbone type Independent rear suspension 1)leaf spring rear suspension 2)coil spring rear suspension Slide 11: MAC-PHERSON STRUT It is simple in construction. The wheel chamber does not vary much. The maintenance is very easy. the most widely used front suspension system in cars It is used in Swift, Wagon R, I10. WISHBONE SUSPENSION: The shock absorber is placed inside the coil spring and is attached to the cross member and to lower wishbone member. It used in Alfa Romeo, Honda Accord, Mazda6 etc. WISHBONE SUSPENSION Advantages ( independent front ): Advantages ( independent front ) Bigger deflection of front wheels, no reaction on steering Greater distance for resisting rolling action Front axle (small-stub), improves road holding tendency of tyres. Minimum vibrations DISADVANTAGES Better shock absorber required. Expensive Tyre wear increases due to transmission of torque. rear end suspension system: rear end suspension system 1)leaf spring Semi-elliptical leaf spring are widely used for suspension in light and heavy duty vehicle. In car these are used for rear suspension. rear end suspension system: rear end suspension system 1)coil spring The energy stored per unit volume is double than leaf spring. Coil springs are provided for progressive stiffness increase load. These spring do not have noise problem and static friction. Advantages ( independent rear suspension): Advantages ( independent rear suspension) Lesser unsprung weight – improves ride , reduces tyre wear. Increased passenger space Rear wheels remain stable .. DISADVANTAGES Increased cost Complicated design Steering action is not proper Air suspension: Air suspension Comprises of compressor , suppling air to air tank Pressure maintained – 5.6 to 7 kg/sq.cm Air bags – on each wheel As load applied , air bags compressed actuating the leveling valve . Air from the tank fills the compressed air bag & hence raise the level of the frame. Air from air bag gets released as load on chassis decreases . Air suspension layout: Air suspension layout Advantages of air suspension : Advantages of air suspension It helps to reduce the load while the vehicle in motion i.e. the dynamic loading as the spring rate variation between laden weight is much less. It gives smooth and comfort ride of the vehicle. The stiffness of the system increases with the increase of the deflection. Hydro elastic Suspension : Hydro elastic Suspension The front and rear suspension units have Hydrolastic displacers, one per side. These are interconnected by a small bore pipe. Each displacer incorporates a rubber spring Damping of the system is achieved by rubber valves. when the front wheel encounter bumps ,the piston moves upwards pressurising the fluid to enter into the rear unit . Slide 21: when the front wheel encounter bumps ,the piston moves upwards pressurising the fluid to enter into the rear unit. Hydroelastic was eventually refined into Hydragas suspension....... Hydro elastic Suspension Hydro gas suspension : Hydro gas suspension Known as hydro-pneumatic suspension. The difference is in the displacer unit itself. In the older systems, fluid was used in the displacer units with a rubber spring cushion built-in. With Hydragas, the rubber spring is removed completely. The fluid still exists but above the fluid there is now a separating membrane or diaphragm, and above that is a cylinder or sphere which is charged with nitrogen gas. The nitrogen section is what has become the spring and damping unit whilst the fluid is still free to run from the front to the rear units and back. Difference …: Difference … Conclusion : Conclusion From the whole discussion in suspension system, I observe that suspension system is like a white blood cell . As white blood cell provides energy to our body to fight against diseases or viruses which try to destroy or try to decrease our life ,in the similar way suspension system provides the energy to a vehicle to protect itself from damaging, increasing life of the vehicle ,increases the handling,increases comfort of passengers and many more. Reference: : Reference: Web:- www.google.com www.findebookee.com www.mypptsearch.com BOOKS:_ AUTOMOBILE ENGINEERING ( G.B.S. NARANG ) Slide 26: THANK YOU !!!