PURPOSE: To avoid reduction of diameter of warm due to increase of gear ratio for same wheel base by increasing the diameter of cutter by the amount corresponding with separation from the wheel base of warm gear set and cutting the gear while inclining more than the crossing angle of both parts.
CONSTITUTION: A hob 7 is positioned while separating by eg-e1 (eg, e1 are the pitch radius of cutter and warm) more than the wheel base (e) between a warm 1 and warm wheel 2 while the radius of hob 7 is increased correspondingly to cut the gear of warm wheel 2 while inclining the hob 7 against the warm 1 by the hob inclination angle (d). Consequently, the warm wheel 2 can be cut into such profile as gearable with the warm 1. Since the diameter of hob 7 can be made larger by eg-e1 than the warm 1, the diameter of hob 7 is never reduced so much as to disable manufacture, or to degrade the productionability of warm wheel 2 considerably or not to withstand against the cutting load even under such specifications of warm gear as to require reduction of diameter of warm 1.
YANAI SETSUYOSHI
NAKAYAMA MASAFUMI
MAKI MITSURU
MAKI MITSURU