The image to the left shows a schematic of a reverted geartrain. There is more than one gearpair and two shafts have two gears. The gears connecting the shafts a and c have a module of 2 mm and those connecting the shafts c and b have a module of 4. One of the most common uses of gear trains is in the gear boxes of cars. Apr 04, 2015 reverted gear train are the compound gear train in which both the axis of the driver and the driven shaft are coaxial.
Simple gear train compound gear train reverted gear train epicyclic gear train 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. Reverted gear train are the compound gear train in which both the axis of the driver and the driven shaft are coaxial. It is a compound gear with, two gearspairs, and a special condition that makes the total number of teeth of the first gearpair equals the number of teeth of the secondgearpair, when the module is the same. The gamebased laboratory for gear train design provides the students with the flexibility to. This causes the ring gear to rotate in a direction opposite that of the sun.
This reverted gear train consists of 4 double spur ge. There is more than one gear pair and two shafts have two gears. The velocity ratio of an epicyclic gear train is determined by the following methods. Remote work advice from the largest allremote company.
Provides teeth counts from any given overall ratio. Epicyclic gear train epicyclic means one gear revolving upon and around another. They are both used when there is only a small space between the input and output shafts and large changes in speed or power are needed. Hi there using compund gear train, we can have a maximum change in power output comparing to simple one. A reverted gear train is very similar to a compound gear train. Types of gear train simple, compound, reverted, epicyclic. A gear train is usually made up of two or more gears. A calculator for designing a multistage compound gear train. Simple compoundgear train n n n n t t t t r nn nn rr rr. The gear 3 which is now the second driver drives the gear 4 i. Thus we see that in a reverted gear train, the motion of the first gear and the last gear is like. This text will not deal with the stress analysis aspects of gear design. Introduction to gear trainsintroduction to gear trains. Jan 17, 2018 for the love of physics walter lewin may 16, 2011 duration.
There are two major differences between compound and reverted gear trains. Helical gear tooth relations, contact of helical gear teeth, gear trainssimple and compound, reverted and epicyclic gear trains. Q3 in a reverted gear train as shown in fig 1 two shafts a. Selecting gear and gear train depending on application. Planetary epicyclic gear ratios equations and calculators. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext.
The reverted gear train is to have a train value o. 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. Reverted gear train applications of reverted gear train. Reverted gear train when the axes of the first gear i. Design of machinery an introduction to the synthesis and. A simple reverted gear train consists of two shafts each of which carry multiple compound spur gears.
A reverted gear train is shown in figure given below, it should be noted that gear 1 and the gear 4 are mounted on the driver and the driven shaft respectively, whose axes are collinear. But in case of epicyclic gear trains, the axes of the shafts on which the gears are mounted may move relative to a. In addition, a questionnaire was administered to the students and then analyzed in order to obtain further anecdotal insights into the students. The image to the left shows a schematic of a reverted gear train. The epicyclic gear train is useful for transmitting highvelocity ratio with a gear of moderate size and in less space. The owner would like your company to manufacture a shop display that is eye catching for passersby. It is a compound gear with, two gearspairs, and a special condition that makes the total number of teeth of the first gear pair equals the number of teeth of the second gear pair, when the module is the same. By allowing both the planet carrier and the ring gear to rotate, a differential gear drive is produced, the output speed of one. In mech designer, it is easier to add compound gear trains than simple gear trains. Works on home computers pc or mac as well as smartphones and tablets. If a motor turns gear a in an anticlockwise direction. Reverted gear train when the axes of the first driver and the last driven are coaxial, then the gear train is known as reverted gear train.
Taking the soft file can be saved or stored in computer or in your laptop. Therefore, it agrees the definition of the compound gear train. 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. Since the sun gear the largest gear is fixed, the dof of the above mechanism is one. So, it can be more than a wedding album that you have. 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. A complete gear train design will necessarily involve considerations of strength of materials and the complicated stress states to which gear teeth are subjected. Thomas bevan, theory of machines, cbs publishers, 2009. Riveted gear train gear ratio is calculated similar to compound gear train.
The reverted gear trains are used in automotive transmissions, lathe back gears, industrial speed reducers, and in clocks where the minute and hour. In this example, gear1 and gear3 are on the same axis. Pdf on aug 18, 2014, amar kumar and others published epicyclic gear train mechanism find, read and cite all the research you need on researchgate. On completion of this short tutorial you should be able to do the following. D rotation of driver per revolution of follower or the driven gear or pulley. Reverted gear train is a special case of compound gear train which will be used to transmit power in coaxial shafts and in this lesson we will study it along with a general concept which is of high use in reverted and epicyclic gear trains. The reciprocal of the speed ratio or velocity is known as train value.
Gear 1 is called a sun gear, gear 2 is a planet, link h is an arm, or planet carrier. Simple compoundgear train n n n n t t t t r nn nn rr rr 26 tttt 16 15 14 15 14 12 23 34 45 56. Let t1 number of teeth on gear 1, r1 pitch circle radius of gear 1, and n1 speed of gear 1 in r. In a reverted gear train, the motion of the first gear and the last gear is same. Sep 15, 2015 i have a design problem that has two predictions that i must make. Theory of machines epicyclic gear trains bysheetal bansal air29ies2014. Homework statement this is a final hurdle of a long question designing a simple gear train. The easiest quirk to way of being is that you can plus save the soft file of solution manual shigley 9th edition in.
Solid mechanics tutorial gear systems this work covers elements of the syllabus for the edexcel module 21722p hncd mechanical principles outcome 3. But in case of epicyclic gear trains, the axes of the shafts on which the gears are mounted may move relative to a fixed axis. Simple gear pair, simple gear trains, planetary gear trains. In automotive design, the automobile layout describes where on the vehicle the engine and drive wheels are found. Two inputs are needed to obtain a predictable output.
In the simplest form, the crash gear box, a collection of spur gears were arranged to give different ratios of input to output speed and in the case of the reverse gear, change the direction of the. We use the method introduced in epicyclic ratio calculation for determining the final gear ratio of an epicyclic gear train. The constants that i am given is the amount of teeth each gear has, the. Another class of gear train has wide application, the epicyclic or planetary train. Jan 11, 2018 a reverted gear train is very similar to a compound gear train. By allowing both the planet carrier and the ring gear to rotate, a. Ok i have 4 spur gears inline, gear a 100 rpm 80 teeth input motor. Types of gear trains asimple gear train bcompound gear. Design, load analysis and optimization of compound epicyclic. Gear trains theory of machines engineering reference with.
When two or more gears are made to mesh with each other to transmit power from one shaft to another, such a combination is called gear train or train of toothed wheels. A reverted gear train input and output shafts are on the same line has a speed ratio of 12 gears i and 2 have a diametral pitch of 8 and gears 3 and 4 have a diametral pitch of 10 no gear is to have less than 24 teeth determine a suitable number of teeth for each gear. Two gears can only mesh if they have the same circular pitch, diametral pitch or module 22 23 12 12 3 3 n rd r nr d. Reverted gear trains are a type of compound gear trains in which input and output shafts are on the same axis. I have a design problem that has two predictions that i must make.
A shop owner has approached your design company to make a mechanical toy based on a head turning. Gear trains theory of machines engineering reference. Reverted gear train pdf following are the different types of gear trains, depending upon the arrangement of wheels. For the love of physics walter lewin may 16, 2011 duration. Theory of machine study notes hand written tom free. 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. 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. Velocity ratios and gear trains for the gear train shown below, determine the train value, output speed. Automobile gear system engine will constantly produce rotaional force with specific speed an. Theory of machine study notes hand written tom free study. Reverted gear train is a special type of gear train which is used to transmit motion and power from one shaft to another shaft. In mech designer, it is easier to add compound geartrains than simple geartrains the image to the left shows a compound gear train.
Many different combinations of engine location and driven wheels are found in practice, and the location of each is dependent on the application the vehicle will be used for. When the axes of the first gear and the last gear are coaxial, then the gear train is known as reverted gear train as shown in figure. 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. Compound reverted gear design project by obadah yaghi on prezi. A compound gear consists of two gears of different pitch diameters attached to one another. Velocity ratios and gear trains for the gear train shown below, determine the train value, output speed, output direction, output torque, and output power. A compound reverted gear train is to be designed as.
Equation and calculators to determine ratios of planetary or epicyclic gear assemblies. Sep 09, 2014 reverted gear train when the axes of the first gear i. Reverted gear train consists of one or more compound gear intermediate gears with input driving and output driven gears. The constants that i am given is the amount of teeth each gear has, the diameter of the gears, the input torque, speed in.
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