Steering System Fundamentals2
Variable ratio gearbox
changes the internal gear ratio as the front wheels are turned fro the center position
Gearbox ratio
comparison between steering wheel rotation ans sector shaft rotation
integral power steering gearbox
contains a worm ans sector gear, hydraulic piston and flow direction valve
spool valve
control the pressure entering the power chambers
electronic four wheel steering
electric motor driven power rack that acts upon the rear wheels via its own recirculating ball drive and mechanical links
Power steering pump
engine driven and produces the hydraulic pressure for steering system operation
Rubber dust boots
fit over the inner ball sockets to keep out road dirt,water and keeps grease in
Power steering hoses
high pressure, hydraulic rubber hoses that connect the power steering pup and the integral gearbox or power cylinder
Power steering reservoir
holds an extra supply fluid
power cylinder
hydraulic cylinder machined inside the rack or gear housing
power piston
hydraulic double acting piston formed on rack
integral piston power steering
hydraulic piston mounted inside the steering gearbox housing
power rack and pinion steering
hydraulic pump pressure to assist the driver in moving the rack and the front wheels
Pressure relief valve
in power steering system to control oil pressure
Worn shaft
input gear connected to the steering column shaft
Parallelogram steering
linkage used with a worm type gear box is commonly
End cover
normally bolts on the housing to cover the end of the sector gear
rotary control valve
operated by a torsion shaft connected to the pinion gear
Sector shaft
output gear from the steering gearbox
external cylinder power steering
power cylinder is commonly bolted to the frame and center link
Adjusting nut
provided to set worm shaft bearing preload
power steering oil cooler
remove excess heat from the oil
Ball nut
rides on the ball bearings and the worm gear
Worm and roller steering gearbox
roller that is mounted on the pinion shaft and meshes with the worm gear
control valve
rotary valve or a spool valve that regulates pressure entry into each end of power cylinder
spool control valve
route oil to the power cylinder
Constant radio gearbox
same gear reduction from full left to right
proportional rack and pinion power steering
senses vehicle speed and steering load to ensure adequate road feel
electronic steering assist
small electric motor to help move the rack and pinion gearbox
Center link
steel bar that connects the right and left sides of the steering linkage
hydraulic lines
steel tubing connecting the control valve and the power cylinder
Idler arm
supports the end of the center link on the passenger side of the vehicle
Ball sockets
they provide for motion in all directions between two connected parts
Pitman arm
transfers gearbox gearbox motion to the steering linkage
Power steering systems
use an engine driven pump and a hydraulic system to assist steering action
Adjusting screw
used to set the sector shaft clearance
hydraulic four wheel steering
uses a power rack and pinion steering system up front
mechanical four wheel steering
uses a special front rack and pinion gearbox with a transfer box
