order code Y the desired cooling option can then B4-KH-17-D Bevel-helical gear Reduction Boxes B4

Flender/Flender Gear Units/Bevel-helical gear Reduction Boxes B4

use the geometry and, hence undercutting, depend on the manufacturing method. Since bevel gears are designed as zero shift gear sets,undercut on generated wheel or pinion may be unavoidable in the worst case. Ifno modication to the geometry is possible, such as an increase in tooth number,change in spiral angle or selection of different tool radius, an even undercuttingdistribution should be ensured. On plunge cut wheels there is no undercut, as it occurs only on generated gears. This means however that larger undercutting occurs on the associated pinions. Therefore, larger prole shift coefcient is necessary toavoid undercutting than would be the case with pinion whose wheel is generated.Only tooth ank generating software (see Sect. 3.3.1 ) will allow to determine exactly whether undercutting will occur, and how much will be present. The choice of the prole shift coefcient also inuences the surface load capacity. The radii of prole curvature of the contacting tooth anks are of crucialimportance for the Hertzian pressure. Apart from the magnitude of the contact stress, prole shift inuences tooth ank sliding which affects load capacity and the occurrence of surface damage such as pitting or micro-pitting (see Sects. 4.1.4 and 4.2.5 ). further criterion for the choice of the prole shift coefcient is therefore the ability to compensate the maximum specic sliding values (see Sect. 2.4.5 ) the pinion and wheel. Too large prole shift can also produce pointed teeth in the heel region (see Fig. 3..6 3 Design Thickness modication coefcient smnAs noted above for the prole shift coefcient hm, the thickness modication coefcient for spiral bevel gears may be varied freely within certain limits. Thickness modication is used to balance tooth root strength between the pinion and the wheel. The change in tooth thickness alters the slot width of the gears which in turn affects the maximum edge radius which can be chosen for the tool. In unfavorable cases, the increase in t