Designing a worm modular cutter

Contents

Introduction

Task

1. Basic calculation

2. Mill Design Parameters

3. Cutter Cutter Features

List of sources used

Introduction

Worm cutters are used for cutting external gear wheels with straight, oblique (screw) and chevron teeth, as well as worm wheels.

In order to obtain a worm cutter that is absolutely accurate in the profile of the tooth being cut, the worm cutter must be in the form of a worm. However, for technological reasons (difficulties in occluding the teeth of the cutter, etc.), worm cutters are usually not profiled on the basis of a beetle worm. An approximate profiling method is used, in which a rectilinear side profile of the mill tooth, that is, a rack with a rectilinear profile, is formed in a section perpendicular to the direction of the mill turn. Less often, worm mills are profiled and made on the basis of an Archimedean worm with a rectilinear profile in axial section, although in this case the errors in the profile of the chub being cut would be less. Thus, due to approximate profiling, worm mills have the so-called

an organic error resulting in some deviation of the profile of the tooth being cut from the involute. However, in most cases, this distortion of the profile is permissible.

Cutting of cylindrical wheels by worm cutters is carried out on tooth-cutting machines. To ensure rolling, the rotation of the cutter and the workpiece to be cut must be agreed on: the number of revolutions of the cutter should be the number of revolutions of the cutter wheel, as the number of teeth of the latter should be the number of revolutions of the cutter. The working movement (cutting movement) is carried out by rotating the cutter, and the feeding movement - by moving the caliper with the cutter along the cut wheel (parallel to its axis).

Cutting teeth with worm cutters is currently the most common method of tooth processing.

Task

Design a worm modular mill for machining gears

crowns Z1 and Z2. Run Mill Drawing

Normal module m = 3.5 mm ;

Degree of accuracy 6

Z1=25; Z2=35

profile angle of initial circuit α = 20 °;

Machined Material Steel 40X

Червячная фреза.cdw