Steering fundamentals Flashcards
what is the purpose of a steering system
to transmit the drivers intentions to the steering tires in a predictable and safe manner while maintaining steering geometry to help reduce tire wear
the steering wheel is connected to the rest of the steering system by the
steering column
the steering column is attached to the
the steering shaft
the steering shaft feeds into
the steering gear
the steering gear is attached to the tires through what linkage
to the pitman arm - drag link - upper steering arm - tie rod assembly - to the right hand lower steering arm - to the right hand steering knuckle
how is the the steering wheel attached to the column
splined
the lower end of the steering shaft it attached to the
worm shaft ( input shaft ) of the steering gear with a split yolk and pinch bolt
what is the purpose of the steering gear
to transmit the drivers intentions from the steering gear to the linkage
what can the steering gear also provide the operator
a mechanical advantage through the gear arrangement to make turning easier . also provides a change in the path of power
what is the pitman arm attached to
the sector shaft
what is the sector shaft
the output shaft of the steering gear
what does the pitman arm change
rotary motion of the sector shaft to linear motion required to move the steering linkage
what is the drag link attached to
one end of the pitman arm and the other to the upper steering arm
how are the front wheels attached to the axle
by a king pin
what is the purpose of the king pin
to act as a pin in the hinge and allow the wheels to turn
what are the two sides of the hinge pin called
the steering knuckle and the I-beam axle
what is carrying the load of the vehicle in the king pin assembly
the thrust bearing
where is the thrust bearing placement in a reverse Elliot axle
on the bottom of the kingpin assembly
what are the purpose of the adjustable steering stops
to limit the amount of pivot of each tire assembly
where are the steering stops located
on the inside of each steering knuckle
what are a few functions of the steering wheel
.provide the steering assembly with input forces
.have buttons for cruise control, engine brake, stereo controls, and horn
.can be equipped with a supplemental restraint system SRS (air bag)
what is the importance of the steering wheel designe
large enough to reduce operator effort and small enough to allow clearance between the seat dash and door
why must the steering wheel be positioned properly
to allow an unobstructed view of the dash gauges and warning lights
what is the normal clock positioning for the steering wheel
10 degrees between 8 - 4 o clock
what holds the horn switch disk away from the contacts
a spring and two plastic washers
what allows a steering wheel with multiple functions to rotate freely in both directions
a clock spring
what could result in damage to the clock spring during maintainance
turning the wheel while the steering shaft is disconnected
what should be an inspection after steering wheel air bag deployment
inspect the clock spring
during a light check if one of the lights stays on what could this indicate
that there is a problem with the srs system and needs to be repaired
when working on a steering column how can you identify the SRS wire
it will be clearly marked or it will be the yellow wire
what are the three types of steering gears
manual steering gear - integral power steering gear - rack and pinion steering
what is the importance of the balls in a ball nut
to provide a type of bearing and reduce clearance between the worm shaft and ball nut . assuring as little play as possible and reducing friction
what is the maximum rotation of travel for sector shaft gear for ball nut travel
30 degrees
what is the purpose of the pitman arm
to turn rotary motion into linear
how is the pitman arm attached to the sector shaft
splined
what is important when attaching the pitman arm to the sector shaft
that they are timed together with the timing marks on both the pitman arm and sector shaft
what is another name for the manual steering gear
Recirculating ball type
can the drag link be used to center the steering wheel
no
why do each end of the drag link need to use a ball socket design
because the pitman arm moves in an arc and the ball sockets allow for a limited amount of change in directional movement as the pitman arm forces the drag link back and forth
is the one piece draglink adjustable
no
what are the two adjustable types of draglinks
two and three piece
what is the purpose of the upper steering arm
to transmit the motion of the drag link to the steering knuckle
what is the purpose of the steering knuckles
to allow each of the wheel/rim assembly to pivot left or right during cornering
if the tiers have been replaced to a wider tire what adjustment must be made to the steering system
adjusting the steering stop screws
what is the minimum clearance tires can have between the frame and other components
1inch or 2.5 cm
why is it important to have specific lower steering arms to each vehicle design based on wheel base
because the angle of the steering arms helps to determine the turning radius of the vehicle
what are two advantages of power steering systems
give the operator road feel and a ease of turning while maintaining quick reaction time
why must the power steering fluid be kept extremely clean
because clearance between the operating components in a power steering system are very small
what are the advantages of a reservoir in a power steering system
.compensates for slight leakage .can transfer absorbed heat .has a filler port .level indicator .allows power steering to vent as it heats and cools .include a filter element
why might you need to add oil coolers to the power steering system
to remove excess heat due to the small size of the reservoir
what is the safety placed into the power steering pump to protect the steering components
a pressure relief valve
what will a pressure relief valve set to low result in
hard steering or poor assist
what will a pressure relief valve set to high result in
chance of steering linkage damage
what is the most common type of power steering gear system
the integral power steering system
the integral power steering system provides a combination of what
hydraulic booster mechanism with the steering gear assembly in a compact unit
in an integral power steering unit what returns the rotary valve to neutral position
torsion bar
in integral power steering gear how is road feel transferred to the operator
through the torsion bar
in a integral power steering gear what replaces the ball nut
a rack piston
what is used to release the pressure at the end of rack piston travel before the steering stops on the steering knuckle contact the axle
a set of poppets
what is one major difference when using dual steering gear systems
they would each have there own set of pitman arms drag links and upper steering arms
what a truck has multiple sets of steering axles it is referred to as what
tandem steering
what still has to be maintained when using tandem steering axles
a mechanical connection
what will you never find attached to a slave gear
a mechanical link
what are the general components of a power steering system
.power steering fluid .reservoir with or without filter .power steering pump .pressure relief valve / flow control .at least one power steering gear .hoses and fittings
