Modified Gear De-Burring Machine Using Kinematic Four-Bar
Transcription
Modified Gear De-Burring Machine Using Kinematic Four-Bar
IJSART - Volume 1 Issue 4 –APRIL 2015 ISSN [ONLINE]: 2395-1052 Modified Gear De-Burring Machine Using Kinematic Four-Bar Linkage Mechanism 1 2 Ajay Sutar , Suhas Patil , Nilesh Langade 3, Dipak Kute 4 Department of Mechanical Engineering 1, 2,3,4 D.Y.Patil College Of Engg,Ambi,Pune,India. Abstract- Today’s Industrial field is very developed .Every day new concepts, new ideas are emerging out with their relevance to industry. New technologies are helping to increase efficiency with less consumption of power. Now days, at the age of automation many of industries are having variety of machines, satisfying the condition available at their best. So accordingly the birth of low cost gear deburring machine took place from high cost, complicated gear deburring machine. become more likely. Radiusing eliminates edge defects, minimizes stress risers and contribute to better mesh and lower operating noise between individual components in a drivetrain. In summary, removing burrs and sharp edges improves the quality, efficiency, performance and reliability of power transmission components. Keywords- Gear deburring, efficiency,low cost. The KEM Deburring Machine as shown in fig.1. has been developed in WERA technical center. Fig.2 shows working of actual gear deburring machine in industry. It has been designed for deburring and chamfering special and bevel gears.The machine concept is used for short serials and a wide variety of work parts. The tool features have five degrees of liberty and is able to perform any work part profile with extreme precision and speed. It also suitable for other complex work part shapes requiring precise and sharp chamfering. I. INTRODUCTION For small scale gear manufacturing industries after manufacturing the gear, deburring of the gear is required for that high costly machines are used. For such small scale units it is not economical to spend more money and space on these types of machines, so there is a need of developing a small unit which consumes less cost and compact. So we design a deburring machine which fulfills this type of requirement of small scale gear manufacturing industries. In our project we focused on deburring of gears of module 1.5 ,2,2.5 ,3 module with different number of teeth by using simple four bar kinematic linkage instead of automatic indexer. We eliminate the various sensors and other auxiliaries parts which are used in the existing industrial gear deburring machine. Here we used gear (work-piece) holding fixture arrangement ( mandrel & chuck), gear indexing mechanism using kinematic four-bar linkage mechanism with uni-directional clutch arrangement facility to be provided for multi-module indexing to accommodate different sizes of spur gear. KEM 502 deburring machine ©FIMAT: Fig.1 II. LITERATURE REVIEW Weiler.[1]Author studied on brushes required for gear demurring They said that all cutting and shaping operations produce some type of burr or leave a sharp edge. On power transmission components such as gears, these undesirable by-products are especially troublesome. Even well-attached, heavy burrs can loosen from the parent edge, either during assembly or in actual operation. These chips are then free to travel through the power transmission system and damage components. Under operating conditions, sharp edges become areas where internal stresses concentrate and failures Page | 144 Fig.2 www.ijsart.com IJSART - Volume 1 Issue 4 –APRIL 2015 ISSN [ONLINE]: 2395-1052 Why chamfer and deburr ? The reasons for choosing a controlled , high-quality of chamfering and deburring process are: • To avoid breakage excessive carburizing along the tooth edges can often cause breakage when the gear is running. • To avoid damaging gears and bearings – If burrs are not removed, they may chip off during the running cycle and cause damage to the other gears and bearings. • To avoid poor tool life in the following finishing processes (see next slide) – Hardened burrs will cause shorter tool life in the following finishing processes The build-up of material along the profile due to chamfering must be straightened in a subsequent rolling cycle. • Removal of sharp burrs reduces the risk of tool handling injuries. In figure (3) are shown two gears , first before the chamfering and deburring operation and the second after these operation. Figure (4)shows a gear with a big burr. Basically there are different types of chamfer: in only one or in both flanks, with a constant size along the profile , with /without chamfer in root diameter. Grinding wheel selection Selection of grinding wheel is based on the following parameters. • Type of abrasive • Grain size. • Type of bond. • Structure of wheel. • Grade. III. METHODOLOGY Design consists of application of scientific principles, technical data and imagination for development of new or improvised machine or mechanism to perform a specific function with maximum economy and efficiency. In our project to design a special purpose machine we have adopted a very very careful approach. Our total design work has been divided into two parts. System design: Fig.3 It mainly concerns the various physical constraints and ergonomics, arrangement of various components on main frame at system, space requirements, man plus machine interactions. It also concerns weight of machine from ground level, total hight of machine and a lot more. Mechanical design: This phase is very important from the view of designer .Many preliminary alternatives are eliminated during this phase. Designer should have sound knowledge of physical properties of material, deformation, loads stresses and failure of material. They know about theories of failure and wear analysis. Mechanical design divides into two types. • Design parts In this detail design is done and dimensions thus obtained are compared to next highest dimension which are readily available in market this simplifies the assembly as well as post production servicing work. Fig.4 Page | 145 www.ijsart.com IJSART - Volume 1 Issue 4 –APRIL 2015 • Parts to be purchased The various tolerances on work pieces are specified in the production drawings. The process charts are prepared and passed on to the manufacturing stage .The parts are to be purchased directly are specified &selected from standard catalogues. ISSN [ONLINE]: 2395-1052 belt, pulley, proximity sensors, , inching switches so machine become compact also cost is reduced. IV. IMPLEMENTATION Four Bar Mechanism: Actual design: In order to understand this machine we have the following block diagram Fig.6 Nomenclature of four bar mechanism Fig.5 Block diagram of gear deburring machine by using four bar kinematic mechanism In existing gear deburring machine auto indexer is used for the purpose of indexing of gear for deburring. It consist various types of proximity sensors, inching switches, variable ac/dc motor, pulley, belts so cost of machine and maintenance cost is high. Existing machine which used is fully automatic for safety purpose covering of machine sound proofing is required so this type of machine is economically deployed in large scale production. But concerning in small or medium scale production unit it is not so much economical .In attempt to that we design a new deburring machine with slight modification. Instead of auto indexer for the purpose of indexing the gear for deburring , simple four bar kinematic chain mechanism which is pneumatically operated with unidirectional clutch is used. We eliminate other parts like Page | 146 A four bar mechanism consists of four rigid link which are linked in the form of quadrilateral by four pin joints. A link that makes complete revolution is called crank, the link opposite to the fixed link is the coupler and forth link is a lever or rocker if oscillates or another crank if rotates. Here r1, r2, r3, r4 are the links of mechanisms. Grashoff’s Law: For a planar four bar type linkage, the sum of the shortest and longest links cannot be greater than the sum of remaining links if there is continuous relative motion between two members. Crank-Rocker Mechanism: It is inversion of four bar mechanism which is used here.In a four bar linkage, if the shorter side link revolves and the other rocks (i.e., oscillates), it is called a crank and rocker mechanism. In this case, there is only a small change, it leaves the smallest side and connect at any of its adjacent side as the frame. Then (in figure) the smallest side „s‟ will have full 360 degree revolution while the other link adjacent to the frame has only oscillating motion (link p). This kind of mechanism is www.ijsart.com IJSART - Volume 1 Issue 4 –APRIL 2015 ISSN [ONLINE]: 2395-1052 hence called a crank-lever mechanism or a crank-rocker mechanism or a rotary-oscillating V. RESULTS After implementation four bar mechanism following results are obtained. Fig.7 crank-lever mechanism Unidirectional clutch: VI. CONCLUSION This machine is suitable for agriculture machinery manufacturing, molded gear industry, timer pulley manufacturing and sprocket and chain wheel manufacturing .etc. Gears of module 1.5 ,2,3 module with different number of teeth can be deburred easily and visual inspection should be possible to evaluate the effective removal of burr. ACKNOWLEDGMENT Fig.8.Unidirectional clutch Unidirectional clutch allows to transmit power in only either direction as shown in fig.8. In other direction it is locked similar to sprocket wheel of cycle. This clutch is used here which help in indexing of gear. During the forward stroke of pneumatic cylinder clutch rotates clockwise direction indexing of gear done. During the return stroke it is not rotates that time deburring of gear takes place by brush and grinding wheel. So this combine indexing and deburring minimizes time. Page | 147 Every orientation works has an impart of many people and it becomes the duty of author to express deep gratitude for the same. We express our special thanks &gratitude to Prof. P.K. Zaware sir for their full support guidance & cooperation in our project. We also thankful to our Hod and staff of mechanical department for assistance and providing necessary help. REFERENCES [1] Weiler. “Gear deburring with power brushes info. Broacher” , form reorder no.: wc357 rev. 5-14 • 5142lp Weiler corporation , 2014 www.ijsart.com IJSART - Volume 1 Issue 4 –APRIL 2015 [2] Mike Magee. “Deburring, Defined” , Gear solutions ,page no 19-23, January 2005 [3] Shuo-jen lee ,Chung ping liu, Tienjung fan and Yi-ho chen., “Deburring Miniature Components by Electrochemical Method”, int. J. Electrochem. Sci.,1713 – 1721 , 1 February 2013 [4] c. Kobialka, Gleason--pfauter, “Contemporary gear pre -machining solutions”, AGMA technical paper, October 2012 [5] Dr. Oliver Winkel , “New Developments in Gear Hobbing”., Gear Technology page.no 45-52 , March/April 2010 [6] Ali Alallak., “Deburring of components a survey of current and future deburring processes”, kth | kungligatekniskahögskolan , September 2010 Page | 148 ISSN [ONLINE]: 2395-1052 www.ijsart.com