Gear train nptel pdf merge

If a simple gear train is used to give a large speed reduction, the last gear has to be very large. Electrical engineering introduction to hybrid and electric. A gear whose axis itself is revolving is called a planetary gear. Usually, following two types of lubrication mechanisms are commonly used for gear lubrication. March 29, 2020 admin medical leave a comment on gear trains nptel pdf. Epicyclic gear train nptel pdf in the first three types of gear trains, the axes of the shafts over which the gears are mounted are. The worm gear can achieve a higher gear ratio than spur gears of a comparable size.

A worm gear is a gear in which a wheel resembles a screw, with parallel helical teeth, while the other is like a normal spur wheel. It may be noted that the motion of the driven gear is opposite to the motion of driving gear. Bevel gears transmit power between two intersecting shafts at any angle or between non intersecting shafts. Gear d 400 rpm 20 teeth output against a load of 200 nm all shafts carry a frictional resistance of 5 nm i need to find. Please start with the tutorial for shaft calculation to see how to introduce geometry and supports for single shafts. Types of gear trains asimple gear train bcompound gear. Gears and gear trains study notes for mechanical engineering. Design of machinery an introduction to the synthesis and. Smaller gear is known as pinion and larger mating gear is called gear. The 24t gear also exists in the form of a crown gear, a special gear with front teeth that can be used like an ordinary 24t, but can also combine with another straight gear to transmit motion in an orthogonal direction. Introduction to mechanisms carnegie mellon school of. This method is extremely methodical, which is appropriate since use of intuition is quite futile with an epicyclic gear train such as the following example. Often gears are treated as pitch cylinder, which roll together without slip as shown in fig.

Mechanical properties of materials nptel pdf wpkuluv. Calculation of a planetary gear train this tutorial shows the usage of mesys shaft calculation with shaft systems. The ring gear 5 is fixed and the gear 2 is rotating. The gear 3 which is now the second driver drives the gear 4 i. The required pressures are generally high and the tools and equipment. The overall gear ratio is the product of all the gear ratios of the gear pairs in the train. Bevel gears are useful when the direction of a shafts. Gate mechanical engineering theory of machines video lecture. Gear trains are widely used in all kinds of mechanisms and machines, from can openers to aircraft carriers. Nptel textile engineering mechanics of textile machinery. Understand gear trains and how to calculate ratios.

Balance shaft and gear train modeling to capture gear rattle. Design, load analysis and optimization of compound. Gear trains mechanical engineering mcq questions and answers. Types of gear train basic, formula and numerical problems of gate previous year questions with solution approach theory of machine, in this. As shown in figure 1, a hev is formed by merging components from a pure. Jan 05, 2015 gear d 400 rpm 20 teeth output against a load of 200 nm all shafts carry a frictional resistance of 5 nm i need to find. Introduction to gear trainsintroduction to gear trains. The gear train consists of five external gears and 4 internal annulus gears, including sun and planet gears forming an epicyclic gear train. Reverted gear train pdf following are the different types of gear trains, depending upon the arrangement of wheels. In absence of lubricant additives and antifriction coating, gears will be subjected to direct friction. Reverted gear train when the axes of the first gear i. That is done but now am not sure of my calculations for power in out and torque in and out, so hopefully someone can help. Gear trains mechanical engineering mcq questions and.

Kinematics of machines nptel online videos, courses. The ring gear 5 is fixed and the gear 2 is rotating at 60 rpn ccw ccwcounterclockwise and cw clockwise. With involute profile of gears, only one contact position experiences pure rolling. In figure 76b a compound ordinary train is seen to be one in which two or more gears may rotate about a single axis. Nptel video lectures, iit video lectures online, nptel youtube lectures, free video lectures, nptel online courses, youtube iit videos nptel courses. Based on the motors output and some measurement and calculation, we would expect an output torque of 6. Gears are compact, positiveengagement, power transmission elements capable of changing. Tabular method for epicyclic gear trains tabular method for epicyclic gear trains theory of machines video tutorial theory of machines video tutorials for gate, ies, and other psus exams preparation and to help mechanical engineering students covering.

The sun gear 2 on the input shaft is a 20 teeth external gear. A gear train may consist of spur, bevel or spiral gears. Gear surfaces coated with boundary additive or antifriction. A gear a mounted on shaft x having 50 teeth drives the gear b having 75 teeth mounted. Thus we see that in a reverted gear train, the motion of the first gear and the last gear is like. To obtain the gear ratio, tv output rateinput rate, of a compound gear train, an illustrated example is presented in this section. Oct 21, 2019 epicyclic gear train nptel pdf merge friction losses can be divided into two major categories. Types of gear ypes of gear ypes of gear ypes of gear trains rains rains rains following are the different types of gear trains, depending upon the arrangement of wheels. Friction losses can be divided into two major categories. First, i found it very difficult to work with this accelerator. The reciprocal of the speed ratio or velocity is known as train value. In absence of lubricant additives and antifriction. The gear train is classified into following types, simple gear train compound gear train riveted gear train epicyclic gear train 1.

A gear train is usually made up of two or more gears. A shop owner has approached your design company to make a mechanical toy based on a head turning. Gears is a positive drive which transmits exact velocity ratio from one shaft to another shaft, gear drive is used when the distance between driver and follower is very less, when two or more gears are made to mesh with each other to transmit power from one shaft to another, the combination is called gear trains gears. The owner would like your company to manufacture a shop display that is eye catching for passers. Simple gear train efficiency and torque help physics forums. The point on the imaginary line joining the centers of the two. Helical gearing, in which the teeth are cut at an angle with the axis of rotation, was developed after spur gearing and has the advantages that has the smoother action and tends to be trainw fig. Usually for a speed reduction in excess of 7 to 1, a simple train is. The stationary gear sun gear or ring gear can be referred to as the central gear. Ch contents contents 428 l theory of machines eatur. A gear train is a set or system of gears arranged to transfer rotational torque from one part of a mechanical system to another, with some gear ratio performing a mechanical advantage. This planetary gear train consists of a sun gear yellow, planet gears blue supported by the. The gt gear train model proved to be a quick, simple tool to accurately predict the stabilizing torque required to eliminate gear rattle in the secondorder balancer gear train the gt model is flexible enough such that future enhancements can be added to obtain more accurate results.

Simple gear train in this type, there is only one gear is mounted on each shaft. These are casting, machining, joining welding, mechanical fastners, epoxy, etc. Nov 09, 2017 gear train types of gear train simple, compound, reverted and epicyclic gear train duration. The owner would like your company to manufacture a shop display that is eye catching for passersby. For example, a truck that uses a diesel to drive a generator, which in turn drives.

In gear train, combination of two or gears are used to transmit power. Types of gear trains basic, formula and numerical problems. Balance shaft and gear train modeling to capture gear. Let t1 number of teeth on gear 1, r1 pitch circle radius of gear 1, and n1 speed of gear 1 in r. The sun gear2 on the input shaft is a 20 teeth external gear. Previous years gate questions on gear trains 200820. Ok i have 4 spur gears inline, gear a 100 rpm 80 teeth input motor.

Ordinary gear trains have axes, relative to the frame, for all gears comprising the train. Modal and stress analysis of gear train design in portal axle using finite element modeling and simulation article pdf available in journal of mechanical science and technology 262. Figure 76a shows a simple ordinary train in which there is only one gear for each axis. Epicyclic gear trains are generally used for automatic transmission, overdrives, and final drives. In some cases, such as the automotive differential, one input is provided the. Whenever a change in the speed or torque of a rotating device is needed, a gear train or one of its cousins, the belt or chain drive mechanism, will usually be used. A gear train is a set or system of gears arranged to transfer rotational torque from one part of a mechanical system to another, with some gear ratio performing a mechanical advantage epicyclic gearing or planetary gearing is a gear system consisting of one or more outer gears, or planet gears, revolving about a central, or sun gear key facts. This chapter will explore the theory of gear tooth action and. There are few explanations i think even in youtube there are not good videos. Gears is a positive drive which transmits exact velocity ratio from one shaft to another shaft, gear drive is used when the distance between driver and follower is very less, when two or more gears are made to mesh with each other to transmit power from one shaft to another, the combination is called gear trains.

The term power transmission is defined as the move ment of. In some epicyclic gear trains, we may find two or more planetary gears. Dynamics of the gear train set in wind turbine article pdf available in materials science forum 697698. In the first three types of gear trains, the axes of the shafts over which the gears are mounted are fixed relative to each other. An epicyclic gear train is shown schematically in the adjacent figure. We use the method introduced in epicyclic ratio calculation for determining the final gear ratio of an epicyclic gear train. The present work on epicyclic gear trains carries out the design of all the gears, shafts, keys and the loads are calculated for individual gears in the epicyclic gear train system. Design, load analysis and optimization of compound epicyclic. Since the gear 1 drives the gear 2, therefore gear 1 is called the driver and the gear 2 is called the driven or follower. Module 2 gears nptel pages 1 17 text version fliphtml5. For the gear train shown below, determine the train value, output speed, output direction, output torque, and output power.

Now, it is to be replaced with 20o involute gear set of module system standard having the same number of teeth and the other dimensions. To find more books about gear trains pdf nptel, you can use related keywords. Nptel syllabus mechanics of textile machinery web course course outline machine elements and drives introduction to drives, selection of drives, primary machine. This is the same convention as used in automotive transmissions. The procedure is to start with the input, and to calculate how the angular velocity propagates through each successive intermeshing pair of gears based upon the number of teeth. Gear trains theory of machines engineering reference with. A twostage planetary gear stage is defined using the program. T1 number of teeth on gear 1, r1 pitch circle radius of gear 1, and n1 speed of gear 1 in r. A gear train is a mechanical system formed by mounting gears on a frame so the teeth of the gears engage gear teeth are designed to ensure the pitch circles of engaging gears roll on each other without slipping, providing a smooth transmission of rotation from one gear to the next.

Apr 04, 20 reverted gear train when the axes of the first gear i. Following are the different types of gear trains, depending upon the arrangement of wheels. I cannot find the working steps for doing gears i couldnt unders. In some epicyclic gear trains, we may find two or more. Compound gear train in this type, two or more gears are. Feb 23, 2017 types of gear train basic, formula and numerical problems of gate previous year questions with solution approach theory of machine, in this video tutorial you will learn about all types of gear. Mar 29, 2020 epicyclic gear train nptel pdf merge sijthre. Epicyclic gearing or planetary gearing is a gear system consisting of one or more outer gears, or planet gears, revolving about a central, or sun gear. Gear train types of gear train simple, compound, reverted and epicyclic gear train duration. Consider a motor driving a rotary load through a gear train, as shown in figure 1.

Mechanical engineering manufacturing processes i nptel. An efficient method of achieving high reduction ratios in minimum space is the use of planetary gearing. Gear trains pdf nptel, gear trains nptel pdf download, gear trains nptel lectures, gear and gear train nptel pdf, gear trains, gear trains theory, gear trains problems, gear trains pdftheory of machine, nptel gear train pdf, gear trains pdftheory of machine for diploma. Gear life depends on effective lubrication, which can be quatified by minimum film trajns to r compositeas shown in fig. Gear trains l 429 transmit motion from one shaft to the other, as shown in fig.

With increase in pitch line velocity, lubricant used should be less viscous in order to min. Hi, i am trying to design a gear train with inventor 20. Pdf modal and stress analysis of gear train design in. The advantage of a compound gear train over a simple gear train is that a much larger speed reduction from the first shaft to the last shaft can be obtained with small gears. Download limit exceeded you have exceeded your daily download allowance. Higher value of t f cause scuffing failure of gears.