B2-DH8-B it dimensions singles tage gear unit sizes to Bevel-helical gear units B2

Flender/Flender Gear Units/Bevel-helical gear units B2

n the past, numerous denitions were made with different perspectives in mind. The main geometry, for example, was described partly in the centre and partly at the heel of the tooth. Since 1 an expert group in the International Organisation forStandardization has concentrated on the basic geometry of bevel gears, creatingthe ISO 2 standard Bevel and Hypoid Gear Geometry, which aims to unifyall the commonly-used methods for the denition of bevel and hypoid geargeometry. Amongst other things, it was agreed that the term bevel gears should be used as generic name, embracing all sub-species like spiral bevel gears, non-offset bevel gears, Zerol gears and hypoid gears. The specic hyponyms will be employed when the following text relates to one or more sub-type. 2.2.2 Basic Geometry Every non-offset bevel gear pair has two cones which roll on each other withoutsliding, just like the pinion and the wheel. The apices of these basic bodies or equivalent rolling cones meet at the point where the axes intersect and remain incontact along common generatrix. The shaft angle is delimited by the axes of the pitch cones 1,2of the bevel gear pair. The generation of cylindrical gear set may be illustrated by means of an imaginary (virtual) rack. In the case of bevel gear, the rack is replaced by ausually planar virtual crown gear whose pitch angle is P9/C1. Figure 2.5shows bevel gear pair with shaft angle 9/C1and the associated virtual crown gear. Figure 2.6describes 3 bevel gear pairs with equal outside diameters but different shaft angles, along with the associated crown wheel in each case.2 2 Fundamentals of Bevel Gears 2.2.3 Gear Dimensions The gear dimensions of non-offset bevel gears are shown in the axial section in Fig. 2.7, and their designations are listed in Table 2.2. Figure 2.8shows Section - from Fig. 2.7. On bevel gears, Section - is dened as the transverse section and is always perpendicular to the pitch cone. Thus, Section - is not plane section in itself, bu