Six-Axis Linkage Strategy and Its Models for Non-Circular Helical Gears Based on Diagonal Hobbing

Abstract

Among cutter teeth of the hob when hobbing non-circular helical gears, there are some issues such as uneven load and wear. To solve those problems, a simultaneous six-axis hobbing model had been developed based on diagonal hobbing. Four probable working conditions were provided. Linkage models corresponding to the four conditions were verified by virtual hobbing, in which the profile accuracies were compared and analyzed. The four working conditions were analyzed including linear (or angular) velocities and linear (or angular) accelerations. Consequently, two implementation strategies including repeating axial shift and reciprocating axial shift were offered. The linkage models and their strategies have been verified by hobbing testing. Experimental results show that diagonal hobbing is superior to non-diagonal hobbing in that the hob life of the former is 3.68 longer than that of the latter, and the micro-topography in the teeth surface of the former is more stable during transmission.

Design of piecewise deformed elliptical gear with closed pitch curve and its conjugate pair

“…As presented in Table 2, ρ ′ min = 69.413 mm, so it can also be verified that the pitch curve of the driven gear is also fully convex. Therefore, the driving and driven gears can be processed by the hobbing or shaping 3,17 . As presented in Table 2, the maximum normal modulus of the driving and driven gears without undercutting in the hobbing process is m nmax = 9.396 mm and m ′ nmax = 0.8.554 mm, respectively, both of which are greater than m n = 4 mm.…”

“…A pressure angle ( γ ) is an intersection angle between the absolute speed direction of the driven gear and the driving gear at the contact point of their pitch curves and the normal direction of their tooth profiles. According to reference 16 , where µ is the diameter-tangent angle 17 of the driving gear, namely, an angle between the polar radius and the positive direction (in which angle θ increases) of the tangent of the diving gear's pitch curve.…”

Technological Aspects in Manufacturing of Non-Circular Gears

“…The value of the parameter A can be calculated from Equation (13). The P2 = r 2 (ϕ 1 ) can be calculated from Equations ( 9) and (10).…”

“…Previous studies [12,13] described a strategy for machining non-circular gears using the diagonal hobbing method.…”