Chapter 10

DRAWING GEAR WHEELS.

Names of the curves and lines of gear teeth 193

How to draw spur wheel teeth 194

Professor Willis' scale of tooth proportions 195

The application of the scale 197

How to find the curve for the tooth face 198

To trace hypocycloides for the flanks of teeth 200

Sectional view of a section of a wheel for showing the dimensions through the arms and hub 202

To draw an edge view of a wheel; rules for drawing the teeth of wheels; bevel gear wheels 203

The construction to find the curves 204

To draw the arcs for the teeth 205

To draw the pitch circle of the inner and small end of the pinion teeth 206

One-half of a bevel gear and an edge view projected from the same 207

A pair of bevel wheels shown in section; drawing of a part of an Ames lathe feed motion; small bevel gears 208

Example in which part of the gear is shown with teeth in, and the remainder illustrated by circles; drawings of part of the feed motion of a Niles horizontal tool work boring mill 209

Three bevel gears, one of which is line-shaded; the construction of oval gearing; Professor Rankine's process for rectifying and subdividing circular arcs 210

Various examples of laying out gear wheels 214