IJIRST 窶的nternational Journal for Innovative Research in Science & Technology| Volume 1 | Issue 7 | December 2014 ISSN (online): 2349-6010
Optimization & Finite Element Analysis of Single Joint Universal Coupling in Automobile Truck Dhwani Sanghani Pursuing Masters Department of Mechanical Engineering Atmiya Institute of Technology & Science, Rajkot
N. D. Gosvami Assistant Professor Department of Mechanical Engineering Atmiya Institute of Technology & Science, Rajkot
Abstract Universal joint in a rigid rod that allows the rod to bend in any direction, and is commonly used in shafts that transmit rotary motion. Due to pin (fork) wear occurs, at the mating surface of the universal coupling. It becomes noisy when rotate at high speed. Our main aim is to replace traditional single joint universal coupling with modern one which having a high strength to withstand desired motion, reduce weight& cost and saving time during assembly of components. It is used in Automobile industry, Food packing machinery, pharma machinery and heavy machinery where Power Torque is to be transmitted between misalign axis. Keywords: Universal Coupling, CREO, Ansys, Assembly, Strength, Stresses. _______________________________________________________________________________________________________ I.
INTRODUCTION
Universal coupling is used in rotating shaft that transmits rotary motion. It is a specialized rotary joint used to allow a rotating split shaft to deflect along its axis in any direction. It is a positive mechanical connection between rotating shafts which are not parallel but intersecting. The flexibility is achieved by constructing the joint with two U-shaped yokes which is joined by a cross shaped hub. One of the yoke is attached to the end of each portion of the split shaft and joined with the cross hub, with the U-sections oriented at 90 degree to each other. It allows the horizontal primary shaft to drive inclined shaft with no friction or loss of speed or drive output potential. It is one of the oldest of all flexible couplings. It is commonly known for its use on automobiles and trucks.
Fig. 1: Universal Coupling
II. LITERATURE SURVEY Reference[1] Two cases of failure in the power transmission system on vehicles: A universal joint yoke and a drive shaft byH. Bayrakceken, S.Tasgetiren, ﾄｰ.Yavuz, Afyon Kocatepe University, Technical Education Faculty, Afyon 03200, Turkey 16 November 2005.In this paper spectroscopic analyses, metallographic analyses and hardness measurements are carried out for universal joint yoke and a drive shaft of an automobile power transmission system. For the determination of stress conditions at the failed section, stress analyses are also carried out by the finite element method. Reference[2] Dynamics of universal joints, its failures and some propositions for practically improving its performance and life expectancy by Farzad Vesali ,Mohammad Ali Rezvani, Mohammad Kashfi August 2012, Volume 26, Issue 8, pp 2439-2449.In this paper analyzing the loading behavior and the surface conditions of the defected bearings. By comparison with the known fatigue theories attempts are made in order to dig into the causes for the failures. Reference[3] An Investigation On Stress Distribution For Optimization Of Yoke In Universal Joint Under Variable Torque Condition: A Review by S G Solanke1 and A S Bharule Vol. 3, No. 2, April 2014.In this paper, an investigation on Stress Distribution for Optimization of Yoke in Universal Joint under Variable Torque Condition. Yoke is analysed under torque load from steering rod observing hot spot Stress concentration region, hot area potentially carrying load. Scope to optimize part by eliminatingdensity in order to maximize area of hot region with reducing in dead region. Reference[4] Finite Element Analysis of Universal Joint Swati N. Datey , S.D. Khamankar, Harshal C. Kuttarmare IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-ISSN:2278-1684,p-ISSN: 2320-334X, Volume 11, Issue 3 Ver. V (May- Jun. 2014), PP 64-69. In this paper,Finite Element analysis of rigid flange coupling is carried out with the help of ANSYS Software for different torque and load condition and it verify by manual calculation.
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Optimization & Finite Element Analysis of Single Joint Universal Coupling in Automobile Truck (IJIRST/ Volume 1 / Issue 7 / 012)
III. BASIC TYPES OF UNIVERSAL COUPLING
Cross Or Spider Type Ring Type Ball & Turnion type Rzeppa type Bendix weeiss type Tracta type
A. Cross Or Spider Type Universal Coupling
Fig. 3.1: Cross or Spider Type Universal Coupling
B. Ring Type Universal Coupling It is a straight modification of the old hook joint. This type of universal coupling is used in automobile drive shaft system.
Fig. 3.2: Ring Type Universal Coupling
C. Ball & Trunnion Type Universal Coupling It is a T-shaped shaft that is enclosed in the body of the joint. The trunnion ends are each equipped with a ball, mounted in needle bearings. and move freely in grooves in the outer body of the joint,, creating a slip joint. Compensating springs at each end of the drive shaft hold it in a centered position. Variations in length is permitted by the longitudinal movement of the balls in the body grooves. Angular displacement is allowed by outward movement of the balls on the trunnion pins. This type of universal coupling is recognized easily by the flexible dust boot that covers it.
Fig. 3.3: Ball & Turnion Type Universal Coupling
D. Rzeppa Type Universal Coupling A Rzeppa joint (invented by Alfred H. Rzeppa in 1926) consists of a spherical inner with 6 grooves in it, and a similar enveloping outer shell. Each groove guides one ball. The input shaft fits in the centre of a large, steel, star-shaped "gear" that nests inside a circular cage. The cage is spherical but with ends open, and it has six openings around the perimeter. This cage and gear fit into a grooved cup that has a splined and threaded shaft attached to it. Six large steel balls sit inside the cup grooves and fit into the cage openings, nestled in the grooves of the star gear.
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Optimization & Finite Element Analysis of Single Joint Universal Coupling in Automobile Truck (IJIRST/ Volume 1 / Issue 7 / 012)
The output shaft on the cup then runs through the wheel bearing and is secured by the axle nut. This joint can accommodate the large changes of angle when the front wheels are turned by the steering system; typical Rzeppa joints allow 45°–48° of articulation, while some can give 54°. At the "outboard" end of the driveshaft a slightly different unit is used. The end of the driveshaft is splined and fits into the outer "joint". It is typically held in place by a circlip.
Fig. 3.4: Rzeppa-Type CV Joint
E. Bendix Weeiss Type Universal Coupling It is used when smoother torque transmission & less structural strength is reuired.4 large balls transmit rotary force with a smaller ball. F. Tracta Type Universal Coupling The Tracta joint works on the principle of the double tongue and groove joint. It comprises only four individual parts: the two forks and the two semi-spherical sliding pieces (one called male or spigot swivel and another called female or slotted swivel) which interlock in a floating (movable) connection. Each yoke jaw engages a circular groove formed on the intermediate members. Both intermediate members are coupled together in turn by a swivel tongue and grooved joint. When the input and output shafts are inclined at some working angle to each other, the driving intermediate member accelerates and decelerates during each revolution. Since the central tongue and groove joint are a quarter of a revolution out of phase with the yoke jaws, the corresponding speed fluctuation of the driven intermediate and output jaw members exactly counteract and neutralize the speed variation of input half member. Thus the output speed change is identical to that of the input drive, providing constant velocity rotation.
Fig. 3.5: Tracta Joint
A coupling of the "Tracta" joint type comprises a driving member rotatable about a first axis, a driven member rotatable about a second axis, and two intermediate members for operatively coupling the driving member to the driven member. The improvement comprises elastomeric bearing means disposed between and engaging each set of mutually opposing bearing surfaces of the driving, driven and intermediate members under compression when torque is applied to the driving member about the first axis. IV. EXISTING MODELING IN SOFTWARE A. Modelling Generation of existing model of universal coupling. Software used : CREO Tools used : Modelling, Assembly
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Optimization & Finite Element Analysis of Single Joint Universal Coupling in Automobile Truck (IJIRST/ Volume 1 / Issue 7 / 012)
Fig. 4.1: Dimensioning of Universal Coupling
Fig. 4.2: Creo Modeling of Universal Coupling
V. CONCLUSION From these papers, all the design criteria’s related to universal coupling will be checked to run this research followed by literatures and reference books, journals etc. Furthermore, this research will conceive some meshing aspects. And comparative analytical results by changing materials, dimensions and other aspects related to use of coupling to minimize weight, wear, noise, cost etc. REFERENCES [1] [2] [3] [4] [5]
[ijesat] international journal of engineering science & advanced technology Volume-2, Issue-3, 690–694 ISSN: 2250–3676 Prof. Siraj MohammdAli Sheikh Rao, S. S. The Finite Element Method in Engineering", Second Edition, Elmsford, NY: Pergamon, 1989. Sevin, & Raymond, Universal Joint and Driveshaft Design Manual, (Warrendale, PA: The Society of Automotive Engineers, 1979) Tathe P.G, Bajaj D.S. 2013 “Review on Failure analysis of yoke assembly of a transmission drive shaft subjected to Torsion and Shear”2013 H.I.F.Evernden,”The propeller shaft or Hooke's coupling and the carden joint", proceedings of the institute of mechanical engineers, Automobile division,2(1),(Jan 1948)
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