Non-full-symmetry involute gear, gear cutting hob special for same, and machining method of non-full-symmetry involute gear

The invention discloses a non-full-symmetry involute gear, a gear cutting hob special for the same, and a machining method of the non-full-symmetry involute gear. The method includes five steps which include: preparing a gear blank which can be used for hobbing, selecting the gear cutting hob special for the non-full-symmetry involute gear, and the like. The axial tooth profile of the gear cutting hob comprises a left tooth profile and a right tooth profile, wherein the left tooth profile comprises linear segments HI, IJ and KL and an arc-shaped segment JK, and the right tooth profile comprises linear segments PO, ON and ML and an arc-shaped segment NM. The end face tooth groove tooth profile of the non-full-symmetry involute gear comprises an involute segment AB, an involute segment EF, a tooth groove left tooth root curve BG and a tooth groove right tooth root curve GE. The non-full-symmetry involute gear has the advantage that the left side and the right side of the teeth of the gear can have different tooth root bending strength. The gear cutting hob can obtain different involute starting points of the a left tooth face and a right tooth face and different tooth root curve curvature radiuses while the left tooth face and the right tooth face of the gear are allowed to have different grinding amount, and defects such as grinding bosses are avoided favorably.