Apparatus for the manufacture or working of gears

In an apparatus for the working of a tooth system of straight or helically toothed workpiece gears comprising a hyperboloidally or globoidally formed toothed tool having an abrasive, chip-removing surface and which has a sufficient axial dimension such that it is in engagement with said workpiece from one axial face of said tooth system of said workpiece to the other axial face thereof, wherein a crossed-axes angle is provided between said workpiece and said tool which defines a workpiece-tool pairing, and wherein said tool and said workpiece are each connected to a guide gear, said guide gears being coupled to one another to define a guide gear pairing, said guide gear pairing having a gear transmission ratio which is the same as a gear transmission ratio of said workpiece-tool pairing and having opposing tooth flanks engaging another with backlash and wherein said workpiece and said tool roll along on another such that during a working operation only a right or a left flank of each tool tooth engages with backlash an opposing tooth flank of said tooth system on said workpiece, the improvement comprising wherein connecting means are provided between said workpiece-tool pairing and said guide gear pairing, said connecting means including a control gear means for adjusting a reciprocal angular position of one of said guide gears and a tool connected thereto for the purpose of changing a flank abutment in said workpiece-tool pairing and in said guide gear pairing and causing said guide gear pairing and said workpiece-tool pairing to operate as a unit and without backlash.