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Today’s wind turbines are capable of converting a great amount of energy in the wind into electricity. This is due to the blades, which are developed using state of the art aerodynamic analysis and the other performance enhancing equipment. In this video, we will explore these different sets of technology in a simple, yet scientific, way. \u003Cdiv style=\"text-align: center;\"\u003E\u003Ciframe width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/qSWm_nprfqE\" frameborder=\"0\" allowfullscreen\u003E\u003C\/iframe\u003E\u003C\/div\u003E\u003C\/p\u003EA detailed webpage version of the video is given below.\u003C\/p\u003E\u003Chr\u003E\u003Cbr\u003E\u003Ch2\u003EThe Basic Working\u003C\/h2\u003E\u003Cp\u003EFirst, let’s get into its basic working.  You might have noticed that even a breezing wind will turn the gigantic wind turbine blades. But how it is possible ? To get answer for this let's have a close look at the wind turbine blade. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-UrKBF1vKSaw\/VuEvQiH4e_I\/AAAAAAAADqc\/4_tVAiDu83A\/s1600\/Wind_turbine_blade_shape.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.1 A wind turbine blade is a collection of different airfoil shapes \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E  The blade has a lot of airfoil cross sections consisting of different sizes and shapes from the root to tip. The simple airfoil technology makes the wind turbine blade turn. That means that a lift force is produced when a fluid moves over an airfoil. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/3.bp.blogspot.com\/-QJIYlck0NcY\/VuFWkVY-DYI\/AAAAAAAADsE\/jHJRuJapCs0\/s1600\/airfoil_technology.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.2 A lift force is generated when flow occurs over an airfoil \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003EYou can note from the Fig.1 that at the root, the airfoil shape is super thick. The reason for this is structural rather than the aerodynamics. At the root mechanical strength required is really high due to the high bending moment induced there.  This way, the wind turbine achieves the basic rotation we are accustomed to seeing. \u003C\/p\u003E\u003Ch2\u003EWind Turbine Blade Design\u003C\/h2\u003E\u003Cp\u003EThe design of wind turbine blade is a clever art.There are aerodynamic reasons behind the complex 3 dimensional shape of wind turbine blade. We will see these factors in this section. \u003Ch3\u003EBlade Tilt\u003C\/h3\u003E\u003Cp\u003EJust as in a moving train, you experience things relatively; the moving wind turbine blade also experiences the wind relatively.  For the moving blade, the relative wind velocity shown in first part of Fig 3. To get relative velocity, you have to vectorially subtract blade velocity from the actual wind velocity. You can note a even if the wind velocity is normal relative velocity is always inclined. Therefore, the wind turbine blade is positioned in a tilted manner in order to align with the relative wind speed. This blade tilt is shown in second part of Fig.3.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-kwJoHck9_04\/VuFWkbc5MHI\/AAAAAAAADr0\/_2h3Phgv-5k\/s1600\/blade_tilt_relative_velocity.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.3 The concept of relative wind velocity and blade tilting \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E\u003Ch3\u003EBlade Twist\u003C\/h3\u003E\u003Cp\u003EBut the problem does not stop here. The blade velocity increases along the length of the blade. So the relative wind speed becomes more inclined towards the tip. To make sure that the relative velocity is aligned at all the cross-sections of the blade a continuous twist is given to the blade from the root to tip.This twist is clearly depicted in Fig.4. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/1.bp.blogspot.com\/-d5JNmFa2KNA\/VuJM68kEy5I\/AAAAAAAADtg\/jGbz3L0EzMA7Y8xdy5v_iiY8EnlXWeyIQ\/s1600\/blade_twist.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.4 Wind turbine blades are always twisted as shown \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E \u003C\/p\u003E\u003C\/p\u003E\u003Ch2\u003EWind Turbine Components\u003C\/h2\u003E\u003Cp\u003ENow we will see different components and accessories used in a wind turbine to enhance its performance. \u003Ch3\u003EGearbox - Increase the rotational speed\u003C\/h3\u003E\u003Cp\u003ENoise produced by the wind turbines is a huge issue around the globe. Higher the speed of the rotor more the noise is. Due to this reason wind turbine rotor is always designed to turn at very low RPM. However, such a low speed rotation cannot be directly coupled to a generator, it will not produce any meaningful electricity frequency. So, before connecting to the generator, the speed is increased in a gearbox. The gearbox uses a planetary gear set arrangement to achieve the high speed ratio. Usually the speed \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/1.bp.blogspot.com\/-iUw8de3wnJk\/VuFWlqcT6SI\/AAAAAAAADso\/mjd5F6h4Dws\/s1600\/gear_box.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.5 A gearbox based on planetary gear arrangement is used to achieve the high speed ratio\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E \u003C\/p\u003E\u003Ch3\u003EFunction of Brake\u003C\/h3\u003E \u003Cp\u003EToo much of wind speed may be catastrophic for a wind turbine. High wind speed will make the blade speed at excessive speed, much above the designed limit and induce a huge centrifugal force. This will eventually lead to blade failure. To arrest the blade rotation during excessively windy condition a brake is used in the nacelle. Usually a maximum limit of 80 km\/hr is set for the cut-off speed.\u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-zaQj2GJmyCc\/VuJKeYK8kDI\/AAAAAAAADtU\/41NpIJo2_LcF81mW7jnSAa07qYXlUidvw\/s1600\/Windturbine_parts.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.6 Different parts of wind turbine are marked here \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E \u003C\/p\u003E \u003Ch3\u003EStep-up Transformer\u003C\/h3\u003E\u003Cp\u003EConsequently, the electricity that is produced is transferred through the cables towards the base, where a step-up transformer is situated. High voltage is always easy to transmit due to the low transmission loss it produces. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-ScSYYQpyfXs\/VuJRrXBx0GI\/AAAAAAAADts\/MGnVivVyt7kE-eou7-pBDB-5yjkNvyFbw\/s1600\/step_up_transformer.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.7 A step-up transformer is usually situated at the base of the wind turbine.\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E\u003C\/p\u003E\u003Ch2\u003EKeep it Aligned with the Wind \u003C\/h2\u003E   \u003Cp\u003ETo extract maximum energy from the wind, it is always needed to keep it aligned with the wind. In this section we will see how the wind turbine is aligned with the wind both in nacelle and blade level. \u003Ch3\u003EThe Yaw Mechanism \u003C\/h3\u003E  \u003Cp\u003EThe blades should face the wind normally for maximum power extraction. But, the wind direction can change at any time. A velocity sensor fitted on the top of the nacelle measures the wind speed and direction. The deviation in the wind’s direction is sent to an electronic controller, which in turn sends an appropriate signal to the yawing mechanism to correct the error. You can see how the yaw motors turn the nacelle. Thus, the wind turbine will always be aligned with the wind direction. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/4.bp.blogspot.com\/-6h2RMX9EhLU\/VuJIDcNDnPI\/AAAAAAAADtI\/gbkw_nEDzWcNLEJnmegJS2j3ncmyPIxeQ\/s1600\/Yaw_Mechanism.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.8 Yaw motors rotate the nacelle to keep it aligned with the wind \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E \u003C\/p\u003E\u003Ch3\u003EOptimizing the Blade Orientation\u003C\/h3\u003E\u003Cp\u003EAccording to the wind speed, the relative velocity angle of the wind also changes. This is clearly depicted in Fig.9. You can see that with the increase in wind speed, relative wind velocity becomes more normal to the blade. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-zTO7I7xayUM\/VuFWmCFS8mI\/AAAAAAAADsw\/FugTEm1zXfw\/s1600\/relative_velocity_change.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.9 A blade tilting mechanism helps to keep the blade aligned with the changing wind relative velocity \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E A blade tilting mechanism tilts the blades and guarantees a proper alignment of the blades with the relative velocity. Fig.10 shows details of how the blade are tilted. Thus the blades are always at the optimum angle of attack with the relative wind flow. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-F8cxnR72BDQ\/VuFWkTFpaiI\/AAAAAAAADr4\/BAywAgMtV50\/s1600\/Blade_tilting_mechanism.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.10 More details of blade tilting mechanism \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E\u003C\/p\u003E\u003Ch2\u003EWind Turbine Efficiency\u003C\/h2\u003E\u003Cp\u003EEfficiency of a wind turbine is a really interesting topic. Historically many crazy attempts have been made to extract the maximum energy from the wind. But all of these attends were no fruitful. In this section we will see why a wind turbine cannot achieve 100% efficiency in a logical way. \u003Ch3\u003ELet's Measure the Wind Speed\u003C\/h3\u003E\u003Cp\u003E To gain a good insight into wind turbine efficiency, assume that you are measuring wind speed at upstream and downstream of a wind turbine. You can note that the wind speed at the downstream is much smaller than the upstream. This is because the blades absorb some kinetic energy from the wind. The same amount of energy is converted as mechanical power of the wind turbine.\u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/1.bp.blogspot.com\/-BikiSS2A6Uc\/VuFWkJoJvDI\/AAAAAAAADro\/QqM_e0VFIS4\/s1600\/velocity_measurement_wind_turbine.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.11 If you measure the wind speed across the wind turbine, you can note that wind speed at the upstream is less than the downstream \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E \u003C\/p\u003E\u003Ch3\u003EIs Zero downstream speed possible ?\u003C\/h3\u003E\u003Cp\u003EIt is interesting to note that a wind turbine absorbs 100% of the available kinetic energy, only if the downstream wind speed becomes zero. However, zero wind speed at downstream is a physically impossible condition.  This cartoon animation clearly depicts this fact. Zero downstream speed simply means that the whole flow is stuck.\u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/2.bp.blogspot.com\/-U9LdPJh3yg0\/VuFWk7vjbZI\/AAAAAAAADsI\/tyWj6X3pwfo\/s1600\/zero_velocity_situation.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.12 Zero wind speed means the whole flow is stuck \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003EThis leads to an interesting conundrum. You will get maximum energy extraction only when the exit speed is zero, but such a condition means there is no flow through wind turbine. It is clear that wind turbine efficiency is zero, when the outlet wind speed is same as the inlet wind speed. This means there exists an optimum value of outlet wind speed between zero and inlet velocity where the efficiency is maximum. \u003C\/p\u003E \u003Ch3\u003EBetz's Limit\u003C\/h3\u003E\u003Cp\u003EThis physical reality of the flow demands a certain amount of exit wind speed. That means that there is a theoretical maximum efficiency a wind turbine can achieve. This limit is known as Betz’s limit. One can theoretically evaluate value of this maximum efficiency value of a Horizontal Axis Wind Turbine. The value turns out to be 59.3 %.  Essentially, it means that no wind turbine in the world can ever cross the efficiency limit of 59.3 %. You can check for the derivation of Betz's limit in a separate article. However Betz's limit is possible only when the turbine has an infinite number of blades and and the blades are rotating at a very high speed. About 40% of mechanical efficiency is practically possible in today's wind turbines. \u003C\/p\u003E\u003C\/p\u003E \u003Cscript async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"\u003E\u003C\/script\u003E\u003C!-- Responsive ad --\u003E\u003Cins class=\"adsbygoogle\"      style=\"display:block\"      data-ad-client=\"ca-pub-2737347269754935\"      data-ad-slot=\"7774217985\"      data-ad-format=\"auto\"\u003E\u003C\/ins\u003E\u003Cscript\u003E(adsbygoogle = window.adsbygoogle || []).push({}); \u003C\/script\u003E"},"link":[{"rel":"edit","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/2466370752380359853"},{"rel":"self","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/2466370752380359853"},{"rel":"alternate","type":"text/html","href":"http:\/\/www.learnengineering.org\/2016\/03\/Wind-turbine-working-design-details.html","title":"Working and Design detials of Wind Turbines"}],"author":[{"name":{"$t":"Sabin M"},"uri":{"$t":"https:\/\/plus.google.com\/113983923192891667856"},"email":{"$t":"noreply@blogger.com"},"gd$image":{"rel":"http://schemas.google.com/g/2005#thumbnail","width":"32","height":"32","src":"\/\/lh4.googleusercontent.com\/-7s2C1CoKPjM\/AAAAAAAAAAI\/AAAAAAAADuk\/p4kg_Q3BKZA\/s512-c\/photo.jpg"}}],"media$thumbnail":{"xmlns$media":"http://search.yahoo.com/mrss/","url":"https:\/\/img.youtube.com\/vi\/qSWm_nprfqE\/default.jpg","height":"72","width":"72"}},{"id":{"$t":"tag:blogger.com,1999:blog-7182417135626013721.post-4742282326812889662"},"published":{"$t":"2015-10-24T02:52:00.001-07:00"},"updated":{"$t":"2016-04-28T01:18:03.392-07:00"},"category":[{"scheme":"http://www.blogger.com/atom/ns#","term":"Manufacturing"},{"scheme":"http://www.blogger.com/atom/ns#","term":"Mechanics"}],"title":{"type":"text","$t":"Understanding Cutting Tool Geometry"},"content":{"type":"html","$t":"\u003Cscript async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"\u003E\u003C\/script\u003E\u003Cscript\u003E  (adsbygoogle = window.adsbygoogle || []).push({     google_ad_client: \"ca-pub-2737347269754935\",     enable_page_level_ads: true   }); \u003C\/script\u003E\u003Cp\u003EThe selection of proper cutting tool geometry is of the utmost importance when doing an effective cutting. In this video, we will provide a clear explanation of the cutting process and tool geometry related to single point cutting tool. \u003Cdiv style=\"text-align: center;\"\u003E\u003Ciframe width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/bUrp8JMRwx4\" frameborder=\"0\" allowfullscreen\u003E\u003C\/iframe\u003E\u003C\/div\u003EA detailed webpage version of the video is given below.\u003C\/p\u003E\u003Chr\u003E\u003Cbr\u003E \u003Ch2\u003E The Basic Cutting Operation\u003C\/h2\u003E\u003Cp\u003ETo remove a metal chip from a work piece, you have to cut along at least 2 surfaces. Cutting along just one surface will not guarantee chip removal. This is clearly shown in the figure below. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/4.bp.blogspot.com\/-wOdeJrSqlzI\/VimEsO81mSI\/AAAAAAAADn8\/5izeewMLTgM\/s1600\/basic_cutting_principle.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.1 To remove a piece of metal from the work piece you have cut through 2 surfaces \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E    For this purpose, cutting tools are provided with 2 cutting edges, a main cutting edge and an auxiliary cutting edge. The main cutting edge cuts the main portion of the chip, while the auxiliary cutting edge cuts the second surface and removes the material. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/3.bp.blogspot.com\/-IDzah24g5kM\/VimFZS2irwI\/AAAAAAAADok\/u-YKyyc2fU0\/s1600\/main_auxiliary_cutting_edges.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.2 A close-up view of main and auxiliary cutting edges \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E    \u003C\/p\u003E\u003Ch2\u003ESingle Point Cutting Tool –  Tool Geometry Details\u003C\/h2\u003E\u003Cp\u003EThe single point cutting tool has many geometrical parameters to make the cutting process more smooth and efficient.  These geometrical parameters also help to enhance the tool life by a great extent. All these details are discussed in this session. \u003C\/p\u003E\u003Ch3\u003ENose Radius\u003C\/h3\u003E\u003Cp\u003EYou can see the smooth corner between the main and auxiliary cutting edges; this corner is known as the nose of the tool. The radius of the nose greatly affects the surface finish of the operation and the strength of the tool.  Sharp nose always produces scratches on the work piece. A blunt nose as shown in the figure eliminates these scratches and gives a good surface finish. Moreover the risk of nose breakage is greatly reduced in a tool with an appropriate nose radius. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/2.bp.blogspot.com\/-FXacgIH4L_I\/VimEs0Rm7dI\/AAAAAAAADoA\/FoSM5mBRYy4\/s1600\/nose_and_rake_angle.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.3 Nose, Rake angle and relief angle make the cutting operation more efficient \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E    \u003C\/p\u003E\u003Ch3\u003ERake Angle\u003C\/h3\u003E\u003Cp\u003EMaterial removal by the main cutting edge is easier when the material’s flowing surface is at an angle, as shown. This angle is known as the rake angle of the tool, more specifically as the back rake angle. The back rake angle greatly affects the chip thickness and the force of the cutting. The rake angle can be positive, zero or negative . A positive rake angle greatly reduces the cutting force . Due to this reason most of the cutting operations are done with a positive rake angle.\u003C\/p\u003E\u003Ch3\u003ERelief Angle\u003C\/h3\u003E\u003Cp\u003ETo avoid the rubbing of the cutting tool with the work piece, a relief angle is provided as shown. The relief angle greatly reduces the tool wear. Please remember that the relief angle has to be positive always. \u003C\/p\u003E\u003Ch3\u003ESide Rake and Relief Angle\u003C\/h3\u003E\u003Cp\u003ESimilar rake and relief angles are also given to the auxiliary cutting edge. To get a better view of the angles a cross-sectional shape is shown in the figure below.\u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/4.bp.blogspot.com\/-o4cGt1P_TFk\/VimGfnZ9BpI\/AAAAAAAADow\/BIFG5B0VM_E\/s1600\/side_rake_relief_angles.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.4 Auxiliary cutting edge is also provided with rake and relief angles \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E   \u003C\/p\u003E\u003Ch3\u003EEnd and Side Cutting Edge Angle\u003C\/h3\u003E\u003Cp\u003ENow, let’s have a look at the tool’s initial position. You can see that the cutting edges form angles, as shown. They are called end and side cutting edge angles.\u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/3.bp.blogspot.com\/-1dJh29b8Khw\/VimEszdiKtI\/AAAAAAAADoE\/hwkK61ZHufU\/s1600\/side_end_cutting_edge_angles.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.5 A view of side and end cutting edge angles \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E  \u003C\/p\u003E\u003Ch2\u003EThe Tool  Signature\u003C\/h2\u003E\u003Cp\u003EThese 7 parameters together, completely define the geometry of a tool. These 7 parameters together known as the signature of a tool. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/3.bp.blogspot.com\/-JDI-zLbI4mg\/VimEsNT858I\/AAAAAAAADn0\/pTASgQ4suZg\/s1600\/Tool_nomenclature.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.6 The 7 parameters discussed so far is known as tool signature \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E    There are different international standards available to represent the the tool signature. However all those standards are interchangeable.\u003C\/p\u003E \u003Cscript async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"\u003E\u003C\/script\u003E\u003C!-- Responsive ad --\u003E\u003Cins class=\"adsbygoogle\"      style=\"display:block\"      data-ad-client=\"ca-pub-2737347269754935\"      data-ad-slot=\"7774217985\"      data-ad-format=\"auto\"\u003E\u003C\/ins\u003E\u003Cscript\u003E(adsbygoogle = window.adsbygoogle || []).push({}); \u003C\/script\u003E"},"link":[{"rel":"edit","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/4742282326812889662"},{"rel":"self","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/4742282326812889662"},{"rel":"alternate","type":"text/html","href":"http:\/\/www.learnengineering.org\/2015\/10\/single-point-cutting-tool.html","title":"Understanding Cutting Tool Geometry"}],"author":[{"name":{"$t":"Sabin M"},"uri":{"$t":"https:\/\/plus.google.com\/113983923192891667856"},"email":{"$t":"noreply@blogger.com"},"gd$image":{"rel":"http://schemas.google.com/g/2005#thumbnail","width":"32","height":"32","src":"\/\/lh4.googleusercontent.com\/-7s2C1CoKPjM\/AAAAAAAAAAI\/AAAAAAAADuk\/p4kg_Q3BKZA\/s512-c\/photo.jpg"}}],"media$thumbnail":{"xmlns$media":"http://search.yahoo.com/mrss/","url":"https:\/\/img.youtube.com\/vi\/bUrp8JMRwx4\/default.jpg","height":"72","width":"72"}},{"id":{"$t":"tag:blogger.com,1999:blog-7182417135626013721.post-7104603657198055370"},"published":{"$t":"2015-08-24T22:45:00.000-07:00"},"updated":{"$t":"2016-04-28T01:18:27.266-07:00"},"category":[{"scheme":"http://www.blogger.com/atom/ns#","term":"Automobile"},{"scheme":"http://www.blogger.com/atom/ns#","term":"Machine Design"},{"scheme":"http://www.blogger.com/atom/ns#","term":"Mechanics"}],"title":{"type":"text","$t":"Manual Transmission, How it works ?"},"content":{"type":"html","$t":"\u003Cscript async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"\u003E\u003C\/script\u003E\u003Cscript\u003E  (adsbygoogle = window.adsbygoogle || []).push({     google_ad_client: \"ca-pub-2737347269754935\",     enable_page_level_ads: true   }); \u003C\/script\u003E\u003Cp\u003EManual transmission, or simply a gearbox, has been serving automobiles well for many decades. Even today it’s the most popular form of transmission. Globally manual transmission accounts for 52% of market share as per 2013 data. In this video, we’ll give a conceptual introduction on the workings of an actual manual transmission with a reverse gear.  \u003Cdiv style=\"text-align: center;\"\u003E\u003Ciframe width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/wCu9W9xNwtI\" frameborder=\"0\" allowfullscreen\u003E\u003C\/iframe\u003E\u003C\/div\u003EA detailed webpage version of the video is given below.\u003C\/p\u003E\u003Chr\u003E\u003Cbr\u003E   \u003Ch2\u003EWhy the Transmission is Required?\u003C\/h2\u003E\u003Cp\u003EThe basic question, is why transmission is required in an automobile?  The power generated by the engine flows through the transmission before it reaches the drive wheels.The basic function of the transmission is to control the speed and torque available to the drive wheels for different driving conditions.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/1.bp.blogspot.com\/-cWVnefU6xVc\/Vdwwze3VBPI\/AAAAAAAADl4\/7GiQwLtraI8\/s1600\/drive_train_automobile.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.1 Power flow in an automobile; the power from engine to drive wheels is transferred through a drive train \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E   For example, if you want to climb a hill, you need more torque. By reducing the speed at the transmission, we will be able to achieve higher torque for the same power input. This is simply conservation of energy. Power transmission through a shaft is torque times angular velocity of the shaft. When you reduce the speed of the shaft, it will automatically result in increase in the torque transmission. Conversely, if the torque demand is low , we can increase the transmission speed. These 2 cases are depicted in Fig.2. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-lok3KAwSRos\/VdAaRzzXwfI\/AAAAAAAADi0\/jav35buRkc0\/s1600\/transmission_use.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.2 During a climb the wheels need more torque; during descent the reverse is the case\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E\u003Ch2\u003EThe Basic Working Principle \u003C\/h2\u003E\u003Cp\u003ENow let’s look at its inner workings. Manual transmissions work on the simple principle of gear ratio. As shown in Fig.3 a different output speed can be achieved by meshing gears of different size. The speed ratio is given by the simple equation shown in the figure (N represents speed, T represents number of teeth). \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-RLhrqywZaRI\/VdppLlFYZiI\/AAAAAAAADlo\/eDmDgmWxyyg\/s1600\/Basic_Principle_Gear_ratio.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.3 The basic principle of a gear pair \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E  \u003Ch2\u003ESliding Mesh Transmission\u003C\/h2\u003E\u003Cp\u003ESliding mesh is the one of the earlier type of manual transmission technology, and the one which is easiest to understand. The most basic slidngmesh transmission mechanism is shown in the Fig.4. Here the input and output shafts are connected through a counter shaft. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-NHpPSSxIaJc\/VdAaRUjONUI\/AAAAAAAADik\/IqUWi3Je_YI\/s1600\/sliding_mesh_transmission_operation.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.4 First and second gear in a sliding mesh transmission; the red line represents the power flow  \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003EThis mechanism can operate under 2 different configurations. In the firs configuration, the output shaft will turn at a slower speed than the input. Just by sliding output gear and connecting the output shaft with the input will result in the second configuration. It is clear that, here the input and out will turn at the same speed. Direction of the power flow is represented as red dotted lines in the Fig.4.   \u003Cp\u003E A 3-speed mechanism will look as shown in the Fig.5. For the gear meshing shown in the figure, the output shaft will rotate at its slowest speed (1\u003Csup\u003Est\u003C\/sup\u003E Gear).It is clear that just by sliding the gears we can achieve different transmission ratios, such as 2\u003Csup\u003End\u003C\/sup\u003E and 3\u003Csup\u003Erd\u003C\/sup\u003E gears.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-8rfOXRwAt4c\/VdA2zMfDFZI\/AAAAAAAADjg\/rv1rrqu3bfc\/s1600\/Three_Speed_Sliding_Mesh.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.5 Three speed sliding mesh transmission: first gear is shown in the figure \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E   \u003Cp\u003EThe sliding mesh transmission is good for controlling the speed, but they have an inherent disadvantage.  It’s quite tricky to slide from one gear and engage with another gear. A technology known as double clutching should be used for achieving a smooth slide of gears. The driver should possess a good skill to do an effective double clutching. Maintenance associated with the double clutch transmissions are quite frequent too.\u003C\/p\u003E\u003C\/p\u003E   \u003Ch2\u003ESolving the Sliding Problem – Synchromesh Transmission\u003C\/h2\u003E\u003Cp\u003E\u003Cp\u003EThe synchro mesh transmission permanently solves this problem. Here the gears are always in mesh, but with a major difference. Here the output gears are loosely connected to the shaft. You can see from Fig.6 that there is a small clearance between the output gears and shaft. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-6zmAxnjX_mY\/VdAxIGzVYTI\/AAAAAAAADjI\/XIlbADqlUTY\/s1600\/synchromesh.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.6 Synchromesh transmission: Here the gear pairs are always in mesh \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E If we connect only one gear to the shaft at a time, the shaft will have the speed of the connected gear.\u003C\/p\u003E\u003Ch3\u003EUnderstanding the basis using a Hypothetical connector\u003C\/h3\u003E\u003Cp\u003EWe will first use a hypothetical connector to illustrate how different gear ratios work in the sycnhromesh transmission. Later on we will move to the actual technology. With the help of the hypothetical connector, different gear ratios are illustrated in Fig.5. It is interesting to note that in 4th gear the input and output shafts are directly connected. This means the output and input shaft will have the same speed in 4th gear. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-tmRDh4SUpm0\/VdnA0B50ZcI\/AAAAAAAADj4\/a5o_bZjO4CM\/s1600\/Hypothetical_Connector.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.7 First and Fourth gear are illustrated in this figure with help of a hypothetical connector \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003EThe art of locking a loosely held gear to the shaft effectively and smoothly lies at the heart of the manual transmission. Let’s see how this is done in actual practice.\u003C\/p\u003E  \u003Ch3\u003ESynchronizer Cone-Teeth Arrangement\u003C\/h3\u003E\u003Cp\u003EFirst of all, the main shaft gears have a synchronizer cone-teeth arrangement as illustrated in Fig.8.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-5swUB5IMv9U\/VdnA0McmC9I\/AAAAAAAADj8\/OT2nilQ1Sv4\/s1600\/Synchronizer_cone_teeth.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.8 Synchronizer cone teeth arrangement of synchromesh transmisson \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E A hub is fixed to the shaft. A sleeve that is free to slide over the hub is also used in this system. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/4.bp.blogspot.com\/-UnIAp-090X4\/VdnD51rZXjI\/AAAAAAAADkM\/rfsXKixaAMw\/s1600\/Sleeve_Hub.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.9 When the sleeve and synchronizer teeth are engaged the locking action can be achieved \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003EIt is clear that, if the sleeve gets connected with the teeth of the synchronizer cone, the gear and shaft will turn together, or the desired locking action will be achieved. But during the gearbox operation, the shaft and gear will be rotating at different speeds. So such a locking action is not an easy task.\u003C\/p\u003E  \u003Ch3\u003EUse of Synchronizer ring\u003C\/h3\u003E\u003Cp\u003EA synchronizer ring helps to match the speed of the gear with that of the shaft. The synchronizer ring is capable of rotating along with the hub, but is free to slide axially. Before moving the sleeve, the clutch pedal is pressed. This way power flow to the gear is discontinued.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-wS0Wc9_Mygs\/VdnFe49XtyI\/AAAAAAAADkY\/95Cvg47zY5g\/s1600\/Synchronizer_Ring.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.10 A synchronizer cone is placed between a hub and synchronzier cone \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003EWhen we move the sleeve, the sleeve will press the synchronizer ring against the cone. Due to the high frictional force between the synchronizer ring and cone, the speed of the gear will become the same as the shaft. At this time, the sleeve can be slid in further, and it will get locked with the gear. Thus, the gear gets locked with the shaft in an efficient and smooth way. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/4.bp.blogspot.com\/-CahbbUu1xQI\/VdnIxmlAWYI\/AAAAAAAADk0\/iLGkgx_vqaA\/s1600\/synchromesh_operation.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.11 Movement of sleeve brings the synchronizer teeth and sleeve to the speed, after that the locking is achieved \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E   \u003Ch2\u003EDifferent Gear Ratios \u003C\/h2\u003E\u003Cp\u003EWhat we have seen in last section was  the technology behind the 2\u003Csup\u003End\u003C\/sup\u003E  gear. In the same way the other gear ratios are also achieved. The details are described in this session.    \u003Ch3\u003EUnder Drive – 1\u003Csup\u003Est\u003C\/sup\u003E, 2\u003Csup\u003End\u003C\/sup\u003E and 3\u003Csup\u003Erd\u003C\/sup\u003E\u003C\/h3\u003E\u003Cp\u003EIn under drive the output shaft turns at a lower speed than the input.  For the manual transmission technology we are explaining 1\u003Csup\u003Est\u003C\/sup\u003E , 2\u003Csup\u003End\u003C\/sup\u003E and 3\u003Csup\u003Erd\u003C\/sup\u003E gear ratios fall under the under drive category. The following figure depicts the sleeve motion required for 1st and 3rd gear. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-SEqzty0X9tc\/VdnHQgmUUrI\/AAAAAAAADkk\/EE4x0G2FoaU\/s1600\/1st_3rd_Gear.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.12 The first and third gear of a manual transmission \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E \u003C\/p\u003E\u003Ch3\u003EDirect Drive\u003C\/h3\u003E\u003Cp\u003EAs the name suggests in direct drive, the output and input shafts turn at the speed. For this purpose the output and input shafts are directly coupled using the synchronizer cone-sleeve mechanism. The hub is fixed to the output shaft, when the sleeve gets connected with the synchronizer teeth of the input shaft, they get coupled together. During the direct drive, the sleeve at the third gear position (2nd part Fig.12) should move to left side.\u003C\/p\u003E\u003Ch3\u003EOver Drive\u003C\/h3\u003E\u003Cp\u003EA 5th gear is used to turn the output shaft at a higher speed than the input shaft. You can note here that unlike the other gear pairs, in 5th gear the output shaft gear is smaller than the counter shaft gear. This generates the overdrive scenario. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-LLUDQzO9YpU\/VdnKkSCg32I\/AAAAAAAADlA\/QtaSHeNSrp0\/s1600\/Over_drive.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.13 The arrangement of 5th gear \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E You can note more difference in the 5th drive configuration, the output gear is fixed to the shaft and the counter shaft gear is loosely connected. As a result synchroizer ring – sleeve mechanism is arranged on the counter shaft. The sole purpose of such an arrangement is to accommodate the reverse gear mechanism. We will see that in next session. \u003C\/p\u003E\u003Cp\u003EThe sleeve motion is controlled by a shift stick . You can also  see the mechanism used for controlling the sleeve with the shift stick. You can note that using this mechanism, not more than one sleeve will be engaged with the output gears. That is important, since engaging 2 sleeves at a time will lead to an impossible turning condition. \u003C\/p\u003E\u003Ch3\u003EThe Reverse Gear\u003C\/h3\u003E\u003Cp\u003ENow let’s see how the reverse gear works? The reverse gear uses a 3-gear arrangement, as shown. Out of those, one is the idle gear. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/4.bp.blogspot.com\/-lozFxoQJ4mc\/VdnZD6KAZeI\/AAAAAAAADlU\/17PeizlLiWY\/s1600\/Reverse_Gear.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.14 The three gear arrangement of a reverse gear \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E It is clear that addition of one more gear will turn the output shaft gear in the reverse direction. For engaging the reverse gear the idle gear is pushed and connected to the other 2 gears. Thus  the required output shaft rotation in the reverse direction can be achieved. Please note here that the reverse gear does not have a synchronizer ring mechanism. This means that, the gearbox rotation has to stop completely before applying the reverse gear. \u003C\/p\u003E\u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/1.bp.blogspot.com\/-mgGikPzE4es\/VdnZDoSLKfI\/AAAAAAAADlQ\/R5xcplEEzJw\/s1600\/Reverse_Working.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.15 The idle gear is pushed and connected with the other 2 gears to achieve the reverse operation \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003Cp\u003EYou might have noticed that in reverse gear, your vehicle moves in a very low speed. As you can see from the figure the three gear arrangement gives speed reduction in 2 stages. This results in very low output speed (high torque). Generally the reverse has a gear ratio of 4:1 (input speed : output speed). \u003C\/p\u003E   \u003Cscript async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"\u003E\u003C\/script\u003E\u003C!-- Responsive ad --\u003E\u003Cins class=\"adsbygoogle\"      style=\"display:block\"      data-ad-client=\"ca-pub-2737347269754935\"      data-ad-slot=\"7774217985\"      data-ad-format=\"auto\"\u003E\u003C\/ins\u003E\u003Cscript\u003E(adsbygoogle = window.adsbygoogle || []).push({}); \u003C\/script\u003E"},"link":[{"rel":"edit","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/7104603657198055370"},{"rel":"self","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/7104603657198055370"},{"rel":"alternate","type":"text/html","href":"http:\/\/www.learnengineering.org\/2015\/08\/Manual-Transmission-Working.html","title":"Manual Transmission, How it works ?"}],"author":[{"name":{"$t":"Sabin M"},"uri":{"$t":"https:\/\/plus.google.com\/113983923192891667856"},"email":{"$t":"noreply@blogger.com"},"gd$image":{"rel":"http://schemas.google.com/g/2005#thumbnail","width":"32","height":"32","src":"\/\/lh4.googleusercontent.com\/-7s2C1CoKPjM\/AAAAAAAAAAI\/AAAAAAAADuk\/p4kg_Q3BKZA\/s512-c\/photo.jpg"}}],"media$thumbnail":{"xmlns$media":"http://search.yahoo.com/mrss/","url":"https:\/\/img.youtube.com\/vi\/wCu9W9xNwtI\/default.jpg","height":"72","width":"72"}},{"id":{"$t":"tag:blogger.com,1999:blog-7182417135626013721.post-7188373855658821700"},"published":{"$t":"2014-11-19T03:33:00.000-08:00"},"updated":{"$t":"2016-04-28T01:19:35.261-07:00"},"category":[{"scheme":"http://www.blogger.com/atom/ns#","term":"Automobile"},{"scheme":"http://www.blogger.com/atom/ns#","term":"Machine Design"},{"scheme":"http://www.blogger.com/atom/ns#","term":"Mechanics"}],"title":{"type":"text","$t":"Torsen Differential, How it works ?"},"content":{"type":"html","$t":"\u003Cscript async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"\u003E\u003C\/script\u003E\u003Cscript\u003E  (adsbygoogle = window.adsbygoogle || []).push({     google_ad_client: \"ca-pub-2737347269754935\",     enable_page_level_ads: true   }); \u003C\/script\u003E\u003Cp\u003ETorsen is a trade mark of the JTEKT Corporation.  The Torsen differential has many patented components and,  is the most unique and ingenious method of providing differential action while overcoming the traction difference problem. This article gives a logical introduction to the working of Torsen differential.\u003C\/p\u003E  \u003Cdiv style=\"text-align: center;\"\u003E\u003Ciframe width=\"720\" height=\"405\" src=\"\/\/www.youtube.com\/embed\/JEiSTzK-A2A\" frameborder=\"0\" allowfullscreen\u003E\u003C\/iframe\u003E\u003C\/div\u003E\u003Cp\u003EA detailed webpage version of the video is given below.\u003C\/p\u003E\u003Chr\u003E\u003Cbr\u003E\u003Ch2\u003EThe internal components\u003C\/h2\u003E\u003Cp\u003EThe internal components of a Torsen are quite different from that of a conventional differential. An exploded view of the Torsen is given in Fig.1.   \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/3.bp.blogspot.com\/-Xx4eHtrjh9A\/VJfybu2On3I\/AAAAAAAADV4\/iRkdhsDuG7I\/s1600\/Torsen_componets.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.1 An exploded view of Torsen differential \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E  At the heart of the system lies a specially shaped gear pair assembly. Let’s see the cross sectional shape of these gears at the mating point. As can be seen, one gear is a spur gear, and the other one is a worm gear.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-UPbUXETyMnw\/VJk3DZLU8TI\/AAAAAAAADWI\/CG_ygbOzhbc\/s1600\/Worm_gear_Worm_wheel.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.2 A worm gear-worm wheel mesh lies at the heart of the Toresn; Cross sectional shape of the figure is shown in the second part  \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E  A Torsen works on the simple principle of worm gear- worm wheel; that is a spinning worm gear can rotate the wheel, but the rotating wheel cannot spin the worm gear.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-yLoMYbRSHJY\/VJlAgSxg_AI\/AAAAAAAADWY\/ETau-jdt5wY\/s1600\/Principle_Torsen.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.3 The worm gear- worm wheel principle lies at the heart of the Torsen operation \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E Throughout this discussion, just keep this principle in mind.  A pair of such worm wheels are fitted with the case, so the engine power received by the case is transferred to the worm wheels.  Each end of the wheels is fitted with a spur gear. As a result, a simplified Torsen differential will look as shown in the Fig.4.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/3.bp.blogspot.com\/-a1TFyHpiWXk\/VJlDYJe2vFI\/AAAAAAAADWs\/o40w1cJ3yK8\/s1600\/Basic%2BComponents.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.4 The complete Torsen differential\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003ENow we will go through different driving scenarios and understand how the Torsen manages to operate the vehicle well.\u003C\/p\u003E\u003Ch2\u003EThe Vehicle Moves Straight\u003C\/h2\u003E  \u003Cp\u003EWhen the vehicle moves straight, the worm wheels will push and turn the worm gears. So both the drive wheels will rotate at the same speed.  Please note here that, in this condition the worm wheels do not spin on its own axis.  In this condition, the whole mechanism moves as a single solid unit.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/1.bp.blogspot.com\/-GNsvkKPKlKU\/VJlXKjxHiwI\/AAAAAAAADW8\/DAfUJEZRtO0\/s1600\/Vehicle_moves_straight.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.5 When the vehicle moves straight, worm wheels just push and turn the worm gears at the same speeds. \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E\u003Ch2\u003EThe vehicle takes a right turn\u003C\/h2\u003E\u003Cp\u003EWhen the vehicle is negotiating a right turn, the left wheel needs to rotate at a higher speed than the right wheel. This fact is clear from the Fig.6. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/3.bp.blogspot.com\/-P6vRUp4Snms\/VK-xSBJdauI\/AAAAAAAADXs\/TaSeFEKJavA\/s1600\/Right_Turn.png\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.6 During a right turn the left wheel has to travel more distance \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E  This speed differential is perfectly supported in a Torsen. Please note that the worm wheel is subjected to relative motion not the absolute motion. The worm wheel is fitted between the case and worm gear, so the relative motion between the case and worm gear is what makes the worm gear turn.\u003C\/p\u003E \u003Cp\u003EThe worm gear of the faster left axle will make the corresponding worm wheel spin on its own axis. On the other side, relative to the case the slow right axle is turning in the opposite direction; thus the right worm wheel will spin in the opposite direction. The meshing spur gears at the ends of worm wheel will make sure that, the worm wheels are spinning at the same speed. Thus it guarantees a perfect differential action. Perfect differential action implies equal amount of speed loss and speed gain to the right and left wheels. With the perfect differential the vehiclce will be able to negotiate a smooth turn.   \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/3.bp.blogspot.com\/-TI3DAajiUWQ\/VK-wbYZqCzI\/AAAAAAAADXg\/txJoaW8-vUk\/s1600\/right-turn-Torsen.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.7 The right worm wheel will spin opposite to the right worm wheel; this is due to the opposite relative motion left worm wheel is experiencing  \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003EWhile taking a left turn the worm wheels will spin in an exact opposite way to that shown in Fig.7.\u003C\/p\u003E\u003Ch2\u003EOvercoming the Traction difference problem\u003C\/h2\u003E  \u003Cp\u003ENow let’s try to understand how the Torsen overcomes the drive wheel traction difference problem.  As you might be aware, when your vehicle encounters a situation as shown, the slippery wheel starts to spin very rapidly and will draw the majority of the engine’s power.  As a result, the vehicle will get stuck. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/3.bp.blogspot.com\/-e-GyAKG2SIc\/VK-x7WmmN7I\/AAAAAAAADX0\/3grwVfkt0wM\/s1600\/traction_difference_problem.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.8 A typical traction difference problem a vehicle is experiencing \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E  But, if a Torsen differential is used in this case, as soon as the slippery wheel starts to spin excessively, the speed change will be transferred to the corresponding worm wheel.  The right worm wheel transfers the speed change to the left worm wheel, since they are connected through spur gears.  Here comes the tricky part! The left side worm wheel will not be able to turn the corresponding worm gear, because, as we said, a worm wheel cannot drive a worm gear!  As a result, the whole mechanism gets locked, and the left and right wheels turn together.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"http:\/\/1.bp.blogspot.com\/-ppcL2vQ4SUc\/VK-yJ9eCEBI\/AAAAAAAADX8\/YJ_K2WTYtsQ\/s1600\/Torsen_Locking_action.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.9 The excessive speed of slipping wheel make the system locked due to the 'basic principle of worm gear-worm wheel' \u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E This allows a large amount of power to be transferred to the high-traction wheel, and the vehicle can thereby overcome the traction difference problem. To carry the load 2 more worm wheel pairs are added.\u003C\/p\u003E  \u003Ch2\u003EPros and Cons of Torsen\u003C\/h2\u003E\u003Cp\u003EIf you are familiar with the other common technologies used to overcome the traction difference problem, you might have noticed a great advantage of the Torsen.  While the other technologies allow the drive wheel to slip for a limited amount of time before it gets locked, in Torsen the locking action is instantaneous. That means as soon as the vehicle encounters a traction difference track the wheels will get locked. They are also compact compared to their counter parts.\u003C\/p\u003E\u003Cp\u003EFollowing are the some disadvantages of the Toresn type (T1) explained here. \u003Cul\u003E\u003Cli\u003ENoisy\u003C\/li\u003E\u003Cli\u003ECostly\u003C\/li\u003E\u003Cli\u003EMore difficult to assemble\u003C\/li\u003E\u003C\/ul\u003E \u003C\/p\u003E \u003Cscript async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"\u003E\u003C\/script\u003E\u003C!-- Responsive ad --\u003E\u003Cins class=\"adsbygoogle\"      style=\"display:block\"      data-ad-client=\"ca-pub-2737347269754935\"      data-ad-slot=\"7774217985\"      data-ad-format=\"auto\"\u003E\u003C\/ins\u003E\u003Cscript\u003E(adsbygoogle = window.adsbygoogle || []).push({}); \u003C\/script\u003E"},"link":[{"rel":"edit","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/7188373855658821700"},{"rel":"self","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/7188373855658821700"},{"rel":"alternate","type":"text/html","href":"http:\/\/www.learnengineering.org\/2014\/11\/Torsen-Differential.html","title":"Torsen Differential, How it works ?"}],"author":[{"name":{"$t":"Sabin M"},"uri":{"$t":"https:\/\/plus.google.com\/113983923192891667856"},"email":{"$t":"noreply@blogger.com"},"gd$image":{"rel":"http://schemas.google.com/g/2005#thumbnail","width":"32","height":"32","src":"\/\/lh4.googleusercontent.com\/-7s2C1CoKPjM\/AAAAAAAAAAI\/AAAAAAAADuk\/p4kg_Q3BKZA\/s512-c\/photo.jpg"}}],"media$thumbnail":{"xmlns$media":"http://search.yahoo.com/mrss/","url":"http:\/\/3.bp.blogspot.com\/-Xx4eHtrjh9A\/VJfybu2On3I\/AAAAAAAADV4\/iRkdhsDuG7I\/s72-c\/Torsen_componets.jpg","height":"72","width":"72"}},{"id":{"$t":"tag:blogger.com,1999:blog-7182417135626013721.post-8219067920659538249"},"published":{"$t":"2014-05-21T19:29:00.001-07:00"},"updated":{"$t":"2016-04-28T01:22:36.998-07:00"},"category":[{"scheme":"http://www.blogger.com/atom/ns#","term":"Automobile"},{"scheme":"http://www.blogger.com/atom/ns#","term":"Machine Design"},{"scheme":"http://www.blogger.com/atom/ns#","term":"Mechanics"}],"title":{"type":"text","$t":"Working of a Limited Slip Differential "},"content":{"type":"html","$t":"\u003Cscript async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"\u003E\u003C\/script\u003E\u003Cscript\u003E  (adsbygoogle = window.adsbygoogle || []).push({     google_ad_client: \"ca-pub-2737347269754935\",     enable_page_level_ads: true   }); \u003C\/script\u003E\u003Cp\u003ELimited slip differentials \u003Ci\u003E(LSD)\u003C\/i\u003E are used in automobile to overcome the traction difference problem of drive wheels. In this article working of \u003Ci\u003ELSD\u003C\/i\u003E is explained in a logical manner.\u003C\/p\u003E\u003Cdiv style=\"text-align: center;\"\u003E\u003Ciframe width=\"640\" height=\"360\" src=\"\/\/www.youtube.com\/embed\/WeLm7wHvdxQ\" frameborder=\"0\" allowfullscreen\u003E\u003C\/iframe\u003E\u003E\u003C\/div\u003EDetailed webpage version of the video is given below. \u003Chr\u003E\u003Cbr\u003E \u003Ch2\u003EProblem with the Standard Differential\u003C\/h2\u003E\u003Cp\u003EConsider a situation where a vehicle fitted with a standard differential moves straight, and one drive wheel is on a surface with good traction and the other wheel is on a slippery track. In a standard differential the left and right axle rotations are completely independent.  Since one wheel is on a slippery track, the standard differential will make that wheel spin in excessive speed, while the good traction wheel will remain almost dead. This means high power supply to the slippery wheel and low power flow to the good traction wheel. So the vehicle won’t be able to move. \u003C\/p\u003E \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/1.bp.blogspot.com\/-CIho-qj6660\/U3yKuMvd6rI\/AAAAAAAADEo\/FJSlPwuRzR4\/s1600\/traction+difference+problem.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.1 In a standard differential power from the engine is transferred to the wheel with low traction\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E   \u003Cp\u003EOne way to overcome this problem is to limit the independency or relative motion between the left and right axles. \u003Ci\u003ELimited slip differentials\u003C\/i\u003E are introduced for this purpose.  One of the most commonly used LSD technology is \u003Ci\u003Eclutch-pack based\u003C\/i\u003E.\u003C\/p\u003E\u003Ch2\u003EConstructional Features of LSD\u003C\/h2\u003E\u003Cp\u003EFirst we will go through constructional features of LSD.\u003C\/p\u003E   \u003Cp\u003EThe basic components of a standard differential are shown below. It has got pinion gear, ring gear, case, spider gears and side gears.   \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/4.bp.blogspot.com\/-hXj9lVxYwew\/U3yKnc25ZYI\/AAAAAAAADD0\/BKeLzDDYwH0\/s1600\/differential+components.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.2 The basic components of a standard differential\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E To understand working of a standard differential please check \u003Ca href=\"http:\/\/www.learnengineering.org\/2014\/05\/working-of-differential.html\" target=\"_blank\"\u003E\u003Cfont color=\"blue\"\u003Ethis link\u003C\/font\u003E\u003C\/a\u003E . Apart from its basic components a Limited slip differential has got a series of friction and steel plates packed between the side gear and the casing. Friction discs are having internal teeth and they are locked with the splines of the side gear. So the friction discs and the side gear will always move together.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/2.bp.blogspot.com\/-LBJqwJXcfTA\/U3yKnQlQV7I\/AAAAAAAADD8\/sqRZE207ke4\/s1600\/LSD_friction_steel+plates.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.3 It is clear from the figure that steel plates are locked with the case and friction disc with the side gear\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E \u003Cp\u003E Steels plates are having external tabs and are made to fit in the case groove. So they can rotate with the case. \u003C\/p\u003E\u003Cp\u003E If any of the clutch pack assembly is well pressed, the frictional force within them will make it move as a single solid unit. Since steel plates are locked with the case and friction discs with the side gear, in a well pressed clutch pack casing and the clutch pack will move together. Or motion from the casing is directly passed to the corresponding axle.\u003C\/p\u003E    \u003Cp\u003E Space between the side gears is fitted with a pre-load spring. Pre load spring will always give a thrust force and will press clutch pack together. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-3HXZfVOYbz8\/U3yKqzNYYyI\/AAAAAAAADEQ\/YxGwrBYFd70\/s1600\/pre-load+spring+LSD.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.4 Pre-load spring in an LSD will always give a thrust force; The blue arrow represents thrust force\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E \u003C\/p\u003E \u003Ch2\u003ESeparating action of Bevel gears\u003C\/h2\u003E\u003Cp\u003EYou can note that spider and side gear are bevel gears. It has got one specialty.  When torque is transmitted through a bevel gear system axial forces are also induced apart from the tangential force. The axial force tries to separate out the gears. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-iSqHz8ui4nI\/U3yKnLMm_NI\/AAAAAAAADDw\/e6dfXAMldlI\/s1600\/bevel+gear+action.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.5 During power transmission through a bevel gear system axial forces are also induced\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E You can note that side gear and axle are 2 separate units. The side gear has got a small allowance for axial movement. \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/4.bp.blogspot.com\/-O2dVLF-5HbQ\/U3yKte0h5OI\/AAAAAAAADEg\/wlDFxT6JuA8\/s1600\/side_spider_gear+axle.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.6 Side gear and axle are two separate units as shown; So the side gear can have small axial movement\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E  So during high torque transmission through spider-side gear arrangement, a high separating thrust force is also transmitted to the clutch pack.  This force presses and locks the clutch pack assembly against wall of the casing.\u003C\/p\u003E   \u003Ch2\u003EWorking of Limited Slip Differential\u003C\/h2\u003E\u003Cp\u003ENow back to the initial problem.  Since one wheel is on a high traction surface, the torque transmitted to it will be higher. So the thrust force developed due to the bevel gear separation action also will be high at that side. Thus clutch pack at high traction wheel side will be pressed firmly and clutch pack will be locked.  So power from the differential casing will flow directly to high traction axle via clutch pack assembly.   \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-Ixfu9l7Jamg\/U3yKqMPeMfI\/AAAAAAAADEI\/d7ahqARbhqc\/s1600\/high+traction+power+flow.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.7 Thrust force induced due to the bevel gear separation action is high for the high traction wheel\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E  On the other hand clutch pack on the low traction wheel side is not engaged yet, so power flow will be limited to that side. So the vehicle will be able to overcome the traction difference problem.  \u003Cdiv align=\"center\" \u003E\u003Ctbody\u003E\u003Cimg alt=\"power flow in automobile\" src=\"https:\/\/3.bp.blogspot.com\/-5HXQfWs21w0\/U3yKrxjgRDI\/AAAAAAAADEY\/lNtdm0eXRC0\/s1600\/right_clutch.jpg\" \/\u003E\u003Cp\u003E\u003Ctr\u003E\u003Ctd  style=\"text-align: center;\"\u003E\u003Cfont size=\"1.95\"\u003EFig.8 Low thrust force at low traction wheel will allow steel plate and friction disc to slip\u003C\/font\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/p\u003E\u003C\/div\u003E\u003C\/p\u003E  \u003Cp\u003EHowever while taking a turn the LSD can act like a normal differential.  In this case thrust force developed due to bevel gear separation action won’t be that high. So the plates in clutch pack will easily overcome frictional resistance and will be able to slip against each other. Thus the right and left wheel can have different speed just like an open differential.\u003C\/p\u003E  \u003Cp\u003EFollowing are the other commonly used technologies used to overcome the drive wheel traction difference problem. \u003Cul\u003E\u003Cli\u003EClutch pack - Pressure disk type\u003C\/li\u003E\u003Cli\u003ETorsen\u003Csup\u003E®\u003C\/sup\u003E\u003C\/li\u003E\u003Cli\u003ECone Differential\u003C\/li\u003E\u003Cli\u003EHydraulic Locking Type\u003C\/li\u003E\u003C\/ul\u003E \u003C\/p\u003E \u003Cscript async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"\u003E\u003C\/script\u003E\u003C!-- Responsive ad --\u003E\u003Cins class=\"adsbygoogle\"      style=\"display:block\"      data-ad-client=\"ca-pub-2737347269754935\"      data-ad-slot=\"7774217985\"      data-ad-format=\"auto\"\u003E\u003C\/ins\u003E\u003Cscript\u003E(adsbygoogle = window.adsbygoogle || []).push({}); \u003C\/script\u003E"},"link":[{"rel":"edit","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/8219067920659538249"},{"rel":"self","type":"application/atom+xml","href":"http:\/\/www.blogger.com\/feeds\/7182417135626013721\/posts\/default\/8219067920659538249"},{"rel":"alternate","type":"text/html","href":"http:\/\/www.learnengineering.org\/2014\/05\/limited-slip-differential.html","title":"Working of a Limited Slip Differential "}],"author":[{"name":{"$t":"Sabin M"},"uri":{"$t":"https:\/\/plus.google.com\/113983923192891667856"},"email":{"$t":"noreply@blogger.com"},"gd$image":{"rel":"http://schemas.google.com/g/2005#thumbnail","width":"32","height":"32","src":"\/\/lh4.googleusercontent.com\/-7s2C1CoKPjM\/AAAAAAAAAAI\/AAAAAAAADuk\/p4kg_Q3BKZA\/s512-c\/photo.jpg"}}],"media$thumbnail":{"xmlns$media":"http://search.yahoo.com/mrss/","url":"https:\/\/1.bp.blogspot.com\/-CIho-qj6660\/U3yKuMvd6rI\/AAAAAAAADEo\/FJSlPwuRzR4\/s72-c\/traction+difference+problem.jpg","height":"72","width":"72"}}]}});