ft extension Force application factor k Gear unit B4-CH-13-D Bevel-helical gear boxes B4

Flender/Flender Gear Units/Bevel-helical gear boxes B4

that at each moment one tooth ank pair is in contact. All meshing positions are therefore considered in predened steps, taking the transmission error into account, with the currently active ank pair contacting at one point. As load increases, the tooth anks deform creating narrow contact ellipse in place of the load-free contact point. prole line is formed by the points with the smallest contact distance which can be determined for each contact position (see Fig. 4.. Points on potential contact line which fall below certain contact distance (usually 3 to 6 , depending on the thickness of the marking compound) at one meshing position at least, constitute the effective contact line and are part of the contact pattern. Those points with the smallest contact distance on each contact line form what is termed the path of contact. Figure 3.1 shows contact pattern in which the contact linesthe major axes of the contact patternare represented. In Fig. 3.1, the short lines perpendicular to the path of contact indicate the transfer points, or the points at which contact is transferred between neighboring tooth pairs. Parameters of the ease-off topography The ease-off allows us to describe the contact geometry very clearly, and also to determine gear set relevant variables such as the position and size of the contact pattern and the transmission error. For this reason, the ease-off topography offers specialists complete information on meshing conditions. It is possible to dene ve parameters for the quantitative description of the ease-off topography, as indicated in Fig. 3.1. Fig. 3.1 Contact pattern with contact lines, path of contact and transfer points3.3 Tooth Contact Analysis 7 There are practical reasons to analyze the ease-off topography using ve parameters. The present case describes crowning in the directions of tooth depth and face width, the mean angular deviation in the prole and lengthwise direction, and twisting between toe and heel. These ve parameters are