Page:Motors and motor-driving (1902).djvu/222

This page has been validated.
190
MOTORS AND MOTOR-DRIVING

8 and 9. Here we have a rod or shaft with a gear wheel at

Fig 8.

one end. This wheel, however, is conical or bevelled (see a, figs. 6 and 7), and the teeth are wider on the outside than upon the inside. It engages with a wheel b upon the axle or other portion of the machinery, which is also bevelled, and bears corresponding teeth. It will be seen that whereas in each of the three methods first described the axes of the motor shaft and wheel axle are parallel, in this case they are at right angles, the forward end of the shaft being united to the motor shaft by a clutch or other suitable means, and rotated by it. In action these bevelled wheels are similar to the gear wheels first described, but instead of revolving lightly on their bearings and pushing round the teeth of the opposite wheel as they come in contact, their shape causes a strong repelling action also to take place, the tendency of the bevelled faces of the gear wheels being to force themselves apart, which throws a considerable cross