gear rack for Machine Tool Industry

After completion of one or two teeth, the blank and cutter stop feeding and the cutter is withdrawn and indexed back again to its starting position, thus enabling a short rack cutter of a practical duration to be utilized. Cutter is again fed back again to depth and cycle is repeated. Number of teeth is managed by the machine gearing, and pitch and pressure angle by the rack cutter. This technique is used for generation of exterior spur gears, being ideally suited for cutting large, dual helical gears. For generating helical tooth, the cutter slides are inclined at the apparatus tooth helix angle.
The hob is fed in to the gear blank to the proper depth and both are rotated together as if in mesh. One’s teeth of the hob cut in to the work piece in successive order and each in a somewhat different position. Each hob tooth cuts its gear rack for Machine Tool Industry china profile depending on the shape of cutter , but the accumulation of these directly cuts creates a curved type of the gear teeth, thus the name generating process. One rotation of the work completes the cutting upto specific depth upto which hob is certainly fed unless the apparatus includes a wide face.

This methodis specifically adopted to cutting large teeth which are tough to cut by formed cutter, and also to cut bevel-gear teeth. It isn’t widely used at the moment.
In gear planing process, the cutter contains accurate involute rack which reciprocates over the face of the blank and the blank rotates in the correct relationship to the longitudinal movement of the cutter as though both roll together as a rack and pinion. Initially the cutter is certainly fed into full tooth depth with cutter reciprocating and blank stationary. Involute form is generated as the blank rotates and involute rack cutter feeds longitudinally.

In the other method, both roughening and finishing cuts are taken with single pointed tools. The usage of the formed tool for finishing is usually impracticable for the larger pitches which are completed by an individual pointed tool. The amount of cuts required depends upon the size of the tooth, quantity of stock to be eliminated, and the kind of material.