Experimental Method of Machining Gears with an Involute Profile Using CNC Lathe with Driven Tools.

Rafał Gołębski

doi:10.3390/ma15031077

Abstract

There are many ways of machining gears; the world’s manufacturers of machine tools have patented many methods that allow for the production of gears in an accurate and efficient way. In general, the patented methods require the use of kinematically complex and expensive CNC machine tools. These tools, moreover, the production of the technology itself, including the machining code, require the use of dedicated software. Therefore, it seems justified to strive for the application of kinematically simple and relatively cheap machines in the machining processes so as to increase the universality and availability of new machining methods. This paper presents a method of machining a spur gear with straight teeth with an involute profile using a basic CNC lathe DMG MORI CLX350V4 equipped with driven tools. On the basis of the presented mathematical model, an algorithm was developed to generate a code that controls the machining of cylindrical gears with an involute profile of straight teeth, with the possibility of modifying the transition profile and the tooth root. The machining was experimental, and the gear was made of aluminium AlSi1MgMn using a solid carbide cylindrical cutter. In conclusion, the presented method was found to be very competitive with commercial methods and is able to provide very high quality gears. The accuracy of the machined profile form deviation in the entire processing did not exceed an average value of 10 μm; while assessing the tooth line, the basis average error was 5 μm. Finally, the gear was assessed as manufactured in accuracy class 6. This machining method guarantees very competitive machining cycle times, and thanks to the use of an uncomplicated CNC lathe and universal tools, it provides great flexibility, at the same time giving the possibility of machining gears with arbitrary profiles.

Highlights

Gear transmissions and their applications gained more and more importance at the turn of the 18th and 19th centuries
Materials and Methods The paper presents a case of machining an involute profile of spur gears as a twoparameter reeling of a tool along a given profile
The following parameters of the gear wheel were determined during the measurements: Fα—profile deviation, the total overlay of the profile form deviation and the profile slope deviation; ffα—form deviation of the profile without consideration of the slope deviation; fHα—profile slope deviation of the profile without consideration of the form deviation; Fβ—tooth line deviation, total overlay of the lead form deviation and the lead slope deviation; ffβ—form deviation of the lead without consideration of the slope deviation; fHβ—lead slope deviation of the outline without consideration of the form deviation

Summary

Introduction

Gear transmissions and their applications gained more and more importance at the turn of the 18th and 19th centuries. Only in theory, presented the methods of constructing a tooth profile as the exact and approximate methods; his development was never used in the construction of the first machine for cutting teeth, which was pointed out by Litvin [2]. Brown [3] developed an application patent method of gear machining and designed the tool, a disk cutter. The patented technology consisted of mapping the shape of the cutting edge of the tool to the outline of the machined tooth. The advantage of the method is that it can be used on simple, non-complicated machine tools. This machining method is still used today

Methods

Results

Discussion

Conclusion