Working principle of gear hobbing machine

Writer： admin Time：2024-07-25 10:11:58 Browse：117℃

Gear hobbing machine is a type of metal cutting machine that uses a gear hobbing tool to machine internal and external spur and helical cylindrical gears, as well as other gear shaped components, using the hobbing method.

Its working principle is mainly based on the meshing principle of a pair of cylindrical gears with parallel axes. The gear hobbing tool is essentially a gear with front and rear angles and cutting edges. ‌

During the gear hobbing process, the gear hobbing tool undergoes up and down reciprocating motion, while the workpiece also accurately rotates one tooth. When the hobbing cutter rotates one tooth back and forth, the workpiece will also rotate synchronously,

At the same time, the gear hobbing cutter will also perform radial feed motion towards the center of the gear blank, thereby cutting out the full tooth height. ‌

The main movements of gear hobbing include:

1. Cutting motion: The up and down reciprocating motion of the hob, with the downward direction being the cutting stroke. ‌

2. Tooth splitting motion: The correct meshing relationship should be maintained between the gear hobbing tool and the workpiece. 

The gear hobbing tool should reciprocate once, and the arc length of the workpiece rotating relative to the tool on the indexing circle is the circumferential feed rate during machining

3. Radial feed motion: In order to gradually cut to full tooth depth, the hobbing tool should have a radial feed rate

4. Move the tool: In order to avoid scratching the machined tooth surface and reduce the wear of the tool teeth,

 when the hobbing tool moves upward, the worktable drives the workpiece to exit the cutting area for a certain distance (radially). ‌

The gear hobbing machine also needs to be equipped with positioning devices, feed devices, bearings, spindles, motors, and other components. 

The motor drives the rotation of the spindle, bearings, and gears to enable the gear hobbing tool to perform precise cutting.

Gear hobbing machines are widely used in industries such as ships, automobiles, machine tools, engineering machinery, printing machinery, mining machinery, etc., 

and have become one of the main equipment for gear processing in these industries.