Ppt belt drives and chain drives powerpoint presentation. Design of v belt drives module belt drives lesson 3. A selection of arrangements of belt drives is shown in the diagram below. Belt drives are used as the source of motion to transfer to efficiently transmit power or to track relative movement. Md14 belt and chain drives university of northern iowa. In a belt drive system, a ratio is used to determine the speed relation between two vbelt pulleys. Pdf pages of our catalog view or download product sections or the complete catalog. Pdf in its simplest form a drive of this type consists of an endless belt fitted tightly over two pulleys driving and driven transmitting motion. We are providing theory of machines by rs khurmi pdf for. A modern development seen on some cars, is a flat belt with a series of mini vees on the inner surface.
Belt drives industrial wiki odesie by tech transfer. Theory of machines by rs khurmi is one of the popular books for mechanical engineering students. There are flat belt and v belt used for the power transmission. This is in contrast to the elastic creep theory which explains the traditional belt drive in terms of longitudinal strains. Power transmission belts are available in several types. Focusing on transmission dynamometers, i will examine a few examples of either. Motors, drives basics of belt drives power transmission belting has been used for more than 200 years. The chain drive is used in bicycles, motorcycles, and many more engines. Used to span large distances or need flexible xmission. Belt drive definition and meaning collins english dictionary. Belt drive, in machinery, a pair of pulleys attached to usually parallel shafts and connected by an encircling flexible belt band that can serve to transmit and modify rotary motion from one shaft to the other.
It is mostly used where a moderate amount of power transmission is required. The journey to improved belt drive reliability begins with knowing and executing the basics. Pdf the steady mechanics of a twopulley belt drive system are examined where the pulley grooves, belt extension and wedging in the grooves, and. The belt rq because of more tension is known as tight side, whereas the belt lm because of less tension is known as slack side, as shown in fig. Belt and chain drives august 15, 2007 2 august 15, 2007 3 objectives understand principles of operation of flexibledrive systems. Flat belt drive is the simplest form of belt drive. In all cases, they operate by fr iction between the belt and the surface of a. Vbelt selection its a veritable cinch machine design. The amount of power transmitted depends upon the following factors. The speed ratio would be stable if slippage did not occur. From driver motor,peddles, engine,windmill,turbine to driven conveyor belt, back wheelsbike,generator rock crusher,dryer. Several ropes also can be used together to transmit more power.
A pulle y reduces these effects with rolling contact between the cable and the machine, but it must be of sufficient size, typi. Timing belts, pulleys, sprockets, and chains for power. Cross sections of vbelt scope this manual covers vbelt drives used primarily for power transmission in industrial applications. One or more v belts may be used on a drive, as required, to transmit the horsepower load. Mechanismsdrives is an introductory treatment of modern mechanical drives, combining the elements of mechanical theory with those of practicality. As everyone knows that theory of machines tom is very tough subject in mechanical engineering. Belt theory friction drives vbelts and vribbed belts the figure to the left illustrates the basic idea of static friction. Types of belt drive,advantage and disadvantage of belt drive. This course is intended for second year diploma automotive technology students with emphasis on study of basics on mechanisms, kinematic analysis of mechanisms, gear drives, can drives, belt drives and study on governor mechanisms. Clamps are available in plastic and aluminum for single and doublesided timing belts. Later, cotton or hemp rope was used with vgroove pulleys to reduce belt tension. Mechanisms drives electromechanical technology series.
Observing signs of unusual belt wear or damage will help troubleshoot possible drive problems. Belt theory friction drives v belts and vribbed belts the figure to the left illustrates the basic idea of static friction. Create a book download as pdf download as epub printable version. Belt and chain drives august 15, 2007 2 august 15, 2007 3 objectives understand principles of operation of flexible drive systems.
Variable frequency drives vfds popular speed control devices used in industrial, commercial and residential applications. One or more vbelts may be used on a drive, as required, to transmit the horsepower load. Maintaining belt drives for best reliability reliabilityweb. If the block weighs w perpendicular to the surface and the force parallel to the surface f can be applied to the side of the block before it begins moving, then the coefficient of static friction. Mechanics and sliding friction in belt drives with. The super ii vbelt was designed specifically for severe drives, and tests show that it lasts far longer than conventional vbelts in these types of applications. Belts systems, types of belts systems flat belt drives article pdf available. Open belt drive open belt drive is used when sense of rotation of both the pulleys is same. The circular belt or rope is circular in section as shown in figure 8. The driver pulley pulls the belt from one side and delivers it to the other side. Thread sprocket onto carrier body until sprocket stops and locks against the washer and carrier body flange fully seating nylatron washer into recess of sprocket. Introduction the belts are used to transmit power from one shaft to another by means of pulleys which rotate at the same speed or at different speeds. Pdf mechanics and sliding friction in belt drives with. A vee section or round section belt in a vee groove will grip better than a flat belt and is.
Problem 2 based on belt drive video lecture from chapter power transmission in theory of machine for mechanical engineering students. Cs34a compensator installation instructions belt drives. Then whenever a change in belt tension occurs due to frictional forces between the belt and the pulley, the belt will extend or contract. Belt transmission dynamometer and torsion dynamometer. Most belt drives consist of flat leather, rubber, or fabric belts running on cylindrical pulleys or of belts with a vshaped cross section running on grooved pulleys. Creep theory the theory assumes that the belt is flexible and extensible, and is sufficiently thin to make shear and bending strains negligible. Belt drive types, advantage and disadvantage mecholic. Wearing gloves, work around the belts, checking for cracks, frayed spots, cuts, or unusual wear patterns. Tc2ps 2 b for softail models with standard cable clutch, 2007 up. A ratio is a proportional factor between two similar objects of different sizes. Belt belts are looped over pulleys belt drive when a belt is used for power transmission it is called a belt drive. Like comment and download belt is a flexible mechanical element that transmit power from one shaft to another belt is a flexible mechanical element that tran slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising.
The mechanical belt drive, using a pulley machine, was first mentioned in the text the dictionary of local expressions by the han dynasty philosopher, poet, and politician yang xiong 5318 bc in 15 bc, used for a quilling machine that wound silk fibers on to bobbins for weavers shuttles. Watch previous videos of chapter power transmission. Some belts are more appropriate for specific applications. In general, the drives are in the integralhorsepower class as distinguished from light duty or fractional horsepower drives. If a belt or cable runs around a fixed shaft, friction between the belt and the shaft can cause the efficiency to be low, and the cable can rapidly wear. The geometrical features of the belt section are indicated in the figure. Mark or note a point on the belt, or on one of the belts in a multiple vbelt drive. But vbelt drive systems, also called friction drives because power is. Page 1 module belt drives version 2 me, iit kharagpur page 2 module belt drives version 2 me, iit kharagpur lesson 3 design of v belt drives version 2 me, iit kharagpur page 3 module belt drives version 2 me, iit kharagpur lesson 3 design of v belt drives version 2 me, iit kharagpur instructional objectives. The design calculations for vbelt drives are based on the pitch line or the. We calculate the relation between the torque m and the beltpulley slip s. Problem 1 based on belt drive power transmission theory of machine. Cross sections of v belt scope this manual covers v belt drives used primarily for power transmission in industrial applications. Idler pulley is a pulley which does not transmit power but assist power transmission by increasing angle of contact of smaller pulley 9.
Insidepenton com electronic design adobe pdf logo tiny, download this article in. The following are the most common types of belt drives used in these days. Free download bucket sort java program with source code. Belt and chain drives objectives introduction introduction. Let d 1 and d 2 be the diameters of driving and driven pulleys, respectively. The person who designs the solution for different engineering problems has to go through the various stages of the design process to arrive at an optimal solution. The belt transmits power by friction contact between the belt and the driving and driven sheave. The friction between the belt and the wheel is further affected by centrifugal force which tends to lift the belt off the wheel. In a two pulley system, the belt can either drive the pulleys in the same direction, or the belt may be crossed, so that the direction of the shafts is opposite. Vbelts drives types, characteristic and industrial. The friction between the belt and wheel may be increased by the shape of the belt. The belt drive is an essential component to the invention of the spinning wheel.
Chain drives are made up of metal which is stronger and more durable. Pdf mechanics and sliding friction in belt drives with pulley. Today the majority of belts in use are of vee cross section, often used in sets of three side by side. Friction, belt, rope and chain drives, toothed wheels, gear trains, gyroscopic couple and precessional motion, inertia. We present numerical results for the ms relation, and for the frictional energy dissipation as a function of the slip, which is important for the rubber wear. They may be used as a source of motion, to efficiently transmit power, or to track relative movement. For a given weight on the belt, the torque to turn the belt is always the same regardless of speed. Belt drives for power transmission are classed as frictional drives. Determine allowable forces and torques for flexibledrive systems, along with the necessary sprockets or sheaves. Determine allowable forces and torques for flexible drive systems, along with the necessary sprockets or sheaves. This is not stronger as compared to the belt drive. Unit 3 power transmission devices power transmission devices.
The book is also a great help for gate examinations. Belt drives a belt is a looped strip of flexible material, used to mechanically link two or more rotating shafts. A wide selection of timing belt clamps for use in linear drive systems is offered. Cross belt drive since power transmitted by a belt drive is due to the friction, belt drive is subjected to slip and creep. Transfer power torque from one location to another. N 1 and n 2 be the corresponding speeds of driving and driven pulleys, respectively.
The theory includes both the belt compliance and the pulley tread block stiffness. Narrow belt sheaves are more compact than classical belt sheaves. In belt drive, little difficulties have when it gets damaged. This can be done using hertz contact stress theory as described in. The pitch line, which is also marked as na, is the neutral axis of the belt section. Tc2bh 2 c 2 open belt drive, 2014 up touring with hydraulic clutch, chrome finish. In a two pulley system, depending upon the direction the belt drives the pulley, the belt drives are divided into two types. Download theory of machines by rs khurmi it is excellent book for practicing problemsolving with adequate theory combined with problems, worked examples, exercise problems at the end of each chapter, complete coverage of syllabus of all indian universities. Printed in great britain mechanics of t h e belt d r i v e t.
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