The Design and manufacturing of straight bevel gears accurately in CNC milling machines

Ill SUMMARY PhD Thesis THE DESIGN AND MANUFACTURING OF STRAIGHT BEVEL GEARS ACCURATELY IN CNC MILLING MACHINES Mak. Yük. Müh. Cihan ÖZEL Fırat University Graduate School of Natural and Applied Sciences Department of Mechanical Engineering 2000, Page: 141 The need of special aimed machine tool for manufacturing straight bevel gears accurately is an important problem for the ones who need only a few of these gears. Since the need for bevel gears to be renewed, because of any reasons, are able to be manufactured in milling machine by module milling cutters approximately, the working gear manufactured becomes unproductive and the service life bevel gear works with it is much more shortened. In our country, since these are limited number of machines for manufacturing bevel gears, the manufacturing of accurately bevel gears is very important problem in small workshops.IV In recent years, considering general aimed CNC miling machinings become wide spread over the country, for meeting the need of a few bevel gears in workshops, it is aimed to develop a general program using CNC. For this aim, firstly all bevel gear manufacturing methods exist already in use were examined. After examining these methods, three kinds of bevel gears manufacturing type that can be used in industry were investigated. These methods are as follow; 1) Matterson apparatus which is used to cut straight bevel gear at shape machines was attached to a classic milling machine and bevel gear were cut by milling cutter without using any special cutter. 2) Using Matterson apparatus at CNC milling machine manufacturing of straight bevel gear was tought for this reason a completely new taper miling cutter was manufactured. Straight bevel gears were manufactured by prepearing two different CNC programs so as to cut right and left gear profiles of the bevel gear with this cutter 3) Preparing a CNC manufacture program straight bevel gears were cut at CNC Dyna milling machine without any apparatus. Straight bevel gears manufactured in three in ways were compared with straight bevel gear used in industry made by East Germany ZFTK 250/1 and their pitch and face roughness were measured and presented in graphs and tables. Key Words: Straight bevel gears, Matterson Apparatus, CNC Milling Machines, Special taper milling cutter.