Design Theory and Experimental Research of Electroplated CBN Plunge Gear Honing Wheel
|School||Taiyuan University of Technology|
|Course||Mechanical and Electronic Engineering|
|Keywords||Plating Cubic Boron Nitride Radial Heng wheel Hard honing Contact line Modification|
Gears and gearing is an important foundation for parts of machinery products. With the development of the machinery manufacturing industry, especially the rapid development of the automobile industry, the demand for gear exponentially grow, and the increasingly high demand for precision gear. From an international point of view, the gear manufacturing technology is moving the manufacturing of high load carrying capacity, high tooth surface hardness, high-precision gear direction forward. Hardened gear used greatly contributed to reduce the weight of the machine, miniaturization and improvement of the quality of performance to a level to make the machine work faster. For example, in the other conditions the same case, instead of quenching and tempering soft tooth surface carburizing hardened gear carrying capacity can be increased by 2 to 3 times, of some hard gear reducer with the same rated power soft tooth surface reducer compared, life can be increased more than three times the weight and volume can be decreased by 40% to 60%. Visible, hardened gears, high-performance. For now, the domestic level of gear manufacturing technology is difficult to meet the production requirements of high-volume, hardened, high-precision gear products, new gear manufacturing gear cutter and its design theory to further improve the technical level of the gear finishing, The method is particularly important. Based on the low accuracy and short life above ideology and electroplated CBN honing wheel tool proposed electroplating CBN the radial honing wheel hard honing technology, research the honing wheel design theory method and development of new honing tool has significance. This article relying Natural Science Foundation of Shanxi Province \(2007g48) \The main research contents are as follows: 1) the application of differential geometry and gear engagement theory of the electroplated CBN radial Heng round design theory. A radial the honing wheel of tooth surface equation, the equation as well as honing tooth of the the Heng tooth surface gear surface contact line to the curve equation, and the processing drum gear the radial Heng tooth surface equation derived applications and thus optimize the design approach to the calculation of the actual analysis of radial the Heng tooth shape and tooth to the amount of modification. The results show that: ① radial honing in line contact, the contact line covers the entire tooth surface in the process of honing, to the Heng wheel is Heng the workpiece gear for the line contact, give full play to the Heng wheel abrasive whole tooth surface cutting action. The theory of radial the Heng round of the tooth surface is not a standard involute helical surface, but a concave beyond surfaces, surfaces through processing involute surface grinding. Dedicated honing wheel ② radial honing wheel is basically the same, involute tooth profile curve, straight teeth radial honing wheel end section of the standard was in concave teeth to its middle end of the cross-section and the basic symmetry, it is only needed teeth to modification. Tooth profile curve of each radial honing wheel, helical gear, each end of the cross-section is not the same, the required amount of modification is not the same, the more distant from the point contact helical line of contact of the tooth surface, and also the greater the amount of modification, it requires and teeth to toothed modification. ③ For the drum-shaped teeth processing by grinding of the radial Heng round to complete, like oblique teeth Heng round, need teeth to simultaneously and tooth grinding. 2) design of Heng round, the primary consideration is the modification of Heng round grinding the heng wheel grinding wheel face what surface contour of both the wheel refurbishment process is simple, and it also enabled the grinding Profile Precision Honing wheel processing to meet the requirements. For this reason, the study of the radial Heng grinding wheel, set up to determine the equation of the grinding wheel face grinding wheel grinding the Heng tooth surface equation. And grinding wheel face processing Heng tooth surface equation to determine the theoretical error of the radial Heng tooth surface grinding, grinding wheel face parameters and the grinding process parameters optimization, use of the accurate radial Heng tooth surface equation honing wheel tooth surface error. Using Face ruled surface of revolution of the grinding wheel grinding radial the Heng wheel, After grinding Helical radial Heng tooth profile tooth surface grinding error of only 1.74μm standard gear. Tooth profile surface grinding straight teeth radial honing wheel full tooth surface maximum error is only 0.07μm, it can be considered the theory of gear tooth surface is processed by the processing error is very small. For the amount of drum-shaped tooth surface, ruled surface of revolution for the face of the grinding wheel grinding Helical radial honing wheel, grinding of the tooth surface theoretical error of up to 6μm about; For straight teeth radial the Heng wheel, the tooth surface error of about 4.5μm, both of which are less than the gear tooth surface of the drum-shaped amount (0.01mm), it will not make machined gear corner point contact occurs. So the processing drum-shaped teeth, straight teeth radial honing wheel needs to be the toothed modification to the gear teeth machined end face of the cross-sectional shape as a standard involute profile. 3) in radial the Heng wheel design theoretical analysis on the basis, further study of the process of electroplating CBN method. Through the formulation of the sample Plating experiments process scheme, respectively, the plating time, the cathodic current density, bath temperature, the three plating process parameters on the number of the center of the test piece, the thickness of the coating of the edge positions, the surface roughness of the coating surface of the coating per unit area of ??pores experimental design and experimental study of the law. According to the analysis and processing of the experimental data: derived empirical formula of the coating thickness of the test piece on the plating time, the cathode current density and the electrolyte temperature on the surface roughness of the coating, the surface of the coating per unit area of ??pores the number of affected law, for guiding the radial The honing wheel matrix design and the choice of the plating process parameters laid a foundation. 4) plating Heng round of state-of-the-art distribution characteristics of the discharge effect, the conventional electroplating trial and auxiliary gear test two methods of experimental research. The results show that: using the auxiliary gear, so that on the the heng wheel matrix various parts in the plating current density was varied reduced reduced on the heng wheel base body edge tip discharge effect, while effectively controlling the tip discharge effect location conducive electroplating process, significantly improved Heng tooth to the distribution of the thickness of the coating metal uniformity and to improve the uniformity of the distribution of the along Heng tooth High direction the thickness of the coating metal, but also improve the bonding strength of the base body of the coating metal and honing knife, to ensure electroplated CBN Honing accuracy of the wheel and the tooth profile of the surface quality, and thus prolong the life of the honing wheel. 5) Based on the above studies, electroplating CBN radial Heng round basic experimental research. For making the electroplated CBN radial Heng round process conducted the analysis, and develop a more reasonable plating process procedures identified electroplated CBN steel tool substrate plating process parameters, namely the cathode current density, bath temperature, plated pH and the bath formula. Electroplating CBN experimental procedures in accordance with the above process and parameters of radial honing wheel vacuum thermal diffusion processing experiment as well as honing wheel, gear honing initial processing experiment further verify the the the radial the Heng wheel design theory correctness and the plating process program feasible , laid a theoretical foundation for further study. This paper put forward innovative radial honing wheel hard honing system depth of the electroplated CBN radial honing wheel design theory analysis, as well as the radial the Heng round of electroplated CBN superhard materials technology program of this hard tooth surface gear manufacturing tool design development of theoretical methods and the development of the new gear cutters has a very important significance.