The invention relates to a fixture assisting an ordinary gear
hobbing machine in
machining an arc-shaped gear. The fixture assisting the ordinary gear
hobbing machine in
machining the arc-shaped gear comprises a positioning device, a rail device, a hand wheel adjusting device, a profiling device, an
idler wheel device and a tension device, wherein the positioning device fixes a gear blank on a working platform of the gear
hobbing machine, the rail device is embedded in the positioning device, the hand wheel adjusting device is simultaneously and fixedly connected with one side, away from an
idler wheel, of the positioning device and one side, away from the
idler wheel, of the rail device, the hand wheel adjusting device can control the rail device to slide back and forth along the connecting line of the center of a gear and the center of a hob, the profiling device is fixedly connected with one side, close to the hob, of the rail device, the idler wheel device is fixedly connected with a knife rest of the hob and can move in the axial direction of the gear along with the knife rest of the hob, and the tension device is connected with the working platform of the gear hobbing machine in a threaded mode. The tension device always pulls and presses the profiling device on the idler wheel device, and a section of working surface which is in the axial direction of the gear and completely in line with a gear
bus is arranged on one face, making contact with the idler wheel device, of the profiling device so that the gear can move in the radial direction of the gear relative to the hob.