Universal JointAnd

Intermittent Motion Mechanism

Group 5Michael Angelo AzadaExel JD Mae BaloloyNoel Angelo Cahayag

Charlene RamirezKeane Cabrera

Rogelio GonzalesJhoemel Flores

UNIVERSAL JOINT

UNIVERSAL JOINT

A mechanical device that allows one or more rotating shafts to be linked together

The most common type of universal joint is the Hooke or Cardan joint.

HISTORYCardan joint- The gimbal suspension used for mounting compasses and the like is sometimes called a Cardan suspension after Italian mathematician and physicist Gerolamo Cardano (1501–1576)Hardy-Spicer joint- Hardy Spicer (company) began operating as a specialist in driveline components to service the automotive industry. The company was incorporated in Victoria in January 1949 and became part of the well known Repco Group in the 1950s.Hooke's joint - Robert Hooke is commonly thought of as the inventor of ‘Hooke's joint’ or the ‘universal joint’.

-The first known application of the universal joint occurred in China more than 2,000 years ago. The Chinese had invented what we call “gimbals,” a series of interlocking rings within a device that allowed a candle placed in the center to remain upright regardless of the device’s position.

A gimbal is a pivoted support that allows the rotation of an object about a single axis. In China, the Han Dynasty (202 BCE – 220 CE) inventor Ding Huan created a gimbal incense burner around 180 CE

Han Dynasty Period206 BC – 220 AD

Degrees of freedom:D.O.F= 3(N-1)-2PD.O.F= 3(2-1)-2(1)D.O.F= 1

To obtain a constant velocity ratio, two Cardan joints are connected. The angle between shaft 2 and 3 and shaft 3 and 4 should be equal.

SEVERAL UNIVERSAL JOINTS WITH CONSTANT VELOCITY RATIO

Universal joints used in toys:- Invented to give a constant velocity ratio-Radii are equal thus it produces constant velocity

-Motion is transmitted from one shaft to the other through 4 balls which fit between raes in the yokes of the shafts.-Races are designed so that the center of each ball lies in the homokinetic plane at all times thus producing a constant velocity ratio.-A fifth ball, center of which lies at the intersection of the shaft’s axes is used in conjunction with a means of locking the parts in assembly and for carrying end thrust.

BENDIX-WEISS JOINT

TRACTA JOINT

RZEPPA JOINT

TRIPOD JOINT

DOUBLE CARDAN

THOMPSON COUPLING

Advantages and Disadvantages of Universal Joint

Advantages:-Universal coupling is more flexible than knuckle joint.-It facilitates torque transmission between shafts which have angular misalignment.-It is cheap and cost effective.-It is simple to be assembled and dismantled.-Torque transmission efficiency is high.-The joint permits angular displacements.

Disadvantages:-Wear may occur if the joint is not properly lubricated.-Maintenance is often necessary to avoid wear.-Universal joint produces fluctuating motion.-It does not support axial misalignment.

INTERMITTENT MOTION

MECHANISM

INTERMITTENT MOTION MECHANISM

- Transforms an incoming motion, generally uniform rotational, in an outgoing progressive or alternating intermittent motion.

- Usually, this intermittent motion is rotational, but it can be also transformed into translator rectilinear motion by means of appropriate transmission mechanism.

HISTORY- There is no said discoverer of the

mechanism.- This mechanism was used in order to for the

fabric to be fed correctly. Through this, the fabric was ensured to be stationary or still while every stich is made when moving the required stitches between distances.

GENEVA WHEEL/ GENEVA MECHANISM- translates a continuous rotation into an intermittent rotary motion. The rotating drive wheel has a pin that reaches into a slot of the driven wheel advancing it by one step. The drive wheel also has a raised circular blocking disc that locks the driven wheel in position between steps.

RATCHET WHEEL/ RATCHET MECHANISM

-A wheel provided with suitably shaped teeth, receiving an intermittent circular motion from an oscillating or reciprocating member, is called a ratchet wheel. -based on a wheel that has teeth cut out of it and a pawl that follows as the wheel turns.

APPLICATIONS

FILM PROJECTORS

This mechanism is used in film projectors, where the film stops in front of the projector bulb for a fraction of a second (usually 1/24th) before moving on.

WATCHES/ MECHANICAL CLOCK

It is also used to interrupt the drive force in a mechanical clock or watch to keep the spring tension within range.

PEN PLOTTER- Pen change mechanism in a pen plotter

AUTOMATED WORK ASSEMBLY TRANSFER LINES

ROTARY TABLE

OTHER APPLICATIONS:- Pen Plotters- Automated Sampling machines- Banknote counting machines- Indexable equipment used in

manufacturing

REFERENCES Borboni, Alberto. Faglia, Rodolfo. “Parasitic Phenomena in the

Dynamics of Industrial Devices”: CRC Press, 2011. Page 267 “Intermittors”.

Bickford, John H. “Mechanisms for Intermittent Motion”. Ithaca, New York: Industrial Press 1972.

Martin, George H. “Kinematics and Dynamics of Machine” http://what-when-how.com/automobile/universal-joints-automobile/

Fundamentals of Motor Vehicle Technology By Victor Albert Walter Hillier

http://gizzardstone.com/2012/08/how-it-works-malta-cross-geneva-mechanism/

http://wikipedia.org http://www.technologystudent.com/cams/ratch1.htm https://www.cs.cmu.edu/~rapidproto/mechanisms/chpt8.html http://nptel.ac.in/courses/112103174/19