Design of Magnetorheological Gear Profile Finishing Tool and Experimental Investigations for Enhancing Gear Transmission Performance

Abstract

The heavy loaded vehicles and high-speed running vehicles are usually produced more noise as well as vibration while reaching at high speed. The noise and vibration in gear box are developed during the meshing of gears teeth. Basic cause of these problem are gears surface asperities, dimensional accuracy, transmission error and their shape accuracy. All these problems are related to the gear cutting operations and the gear teeth profile surface finishing. The challenge related to the gear teeth finish can be overcome by the super finishing of the gear teeth profile precisely and with their more shape accuracy. A new magnetorheological fluid-based finishing process is developed for finishing gear teeth profile. In this process, to finish the gear teeth in nanometer range, a magnetorheological gear profile finishing (MRGPF) tool is designed and fabricated. The MRGPF tool is made likely similar to the gear grinding profile wheel tool. The present finishing work performed after the grinding of gear profile and compared the results obtained with the present MRGPF process. The magnetostatic finite element analysis (FEA) of the present developed MRGPF tool was done in Maxwell Ansoft V13. On the basis of FEA for magnetic flux density distribution on its finishing surface, the MRGPF tool has been designed. The present work is concerned with the influence of reduction in surface roughness on the gear performance (made with the material of EN24 having 62 HRC) after its profile finishing with present designed tool. The detailed design of experiments has been carried out using the response surface methodology. The spur gear is used in the present work with 3 module gear teeth profile and 12 numbers of teeth. The variable parameters taken are feed of tool, rotation of tool, and variable of working gaps between the tool surface and workpiece surface to optimize the process performance. The average surface roughness is reduced from 160nm to the 20nm after the present MRGPF process with a single tooth in 20 minutes. Also, the DIN standard is reduced from DIN 6 to the DIN 4. Thus, the present developed MRGPF tool is found capable to reduce the surface roughness and improve the surface characteristics after the gear grinding process. The benefits of the super-finished gear profile surface can be estimated in terms of improvement in scuffing performance, reduction of noise in gear box, reduce the wear rate on gear teeth profile surface while meshing and also give lower friction and bulk temperatures during operation.