Lesson 1/Learning Event 1
FIGURE 6. CAM AND LEVER STEERING GEAR.
CAM AND LEVER STEERING GEAR
In the cam and lever steering gear, the worm is known as a cam. The inner
end of the pitman arm shaft has a lever that contains a tapered stud. The
stud engages in the cam so that the lever is moved back and forth when the
cam is turned back and forth.
When the tapered stud is fixed in the lever so that it can't rotate, there
is sliding friction between it and the cam. Therefore, on some vehicles
with this type of steering gear, the stud is mounted in bearings so that it
rolls in the cam groove (threads) instead of sliding.
Some large trucks use a cam and twinlever steering gear. This is nothing
more than a cam and lever gear with two tapered studs instead of one. The
studs may be fixed in the lever, or they may be mounted on bearings.