Brochure

Glossary
Ackerman Principle: An alignment principle based on
vehicle tread width and wheelbase upon which turning
angle is computed.
Ackerman Arm: A steering component, which provides
interconnection between the outer tie rod and spindle.
Alignment: The process of measuring and adjusting the
position of all wheels attached to a common chassis.
Angle: Two intersecting lines that are not parallel.
Arc: Any part of a circle or a cur ved line.
Axial Play: Vertical movement of the wheel and tire
assembly when inspecting a kingpin.
Balance: This term is used to describe having equal
weight distribution about the circumference of a wheel
and tire assembly
.
Bead: A wire steel coil forming an anchor for individual
plies and rim attachment of a tire.
Bellows: A r
ubber type seal, which is folded to allow
for a telescopic action. Normally referred to as a
bellows boot.
Bias Belted: A bias ply tire that has reinforcing strips
or belts under the tread section.
Bias Ply: A tire constructed of alternate plies, which
intersect the tire centerline at approximately 35 degrees.
Body Roll: The leaning of the vehicle body
while cornering.
Braking Control: Vehicle stability related to the
reaction under all stopping conditions.
Bushing: A component made of metal or rubber-type
material, used to isolate interconnected moving parts.
Cam Bolt: A bolt and eccentric assembly which, when
rotated, will force components to change position.
Camber: The inward or outward tilt of the wheel.
Camber Roll: A change in camber brought about by
suspension changes while cornering.
Caster: The forward or rearward tilt of the steering axis.
Center Bolt: A bolt that provides centering and
attachment of an axle and spring assembly
.
Centerline Steering: A centered steering wheel while
the vehicle is traveling a straight ahead course.
Chassis: All major assemblies on a vehicle including
suspension, steering, drivetrain, and frame. Ever ything,
except the body
.
Circumference: The total distance around a circle.
Concentric: Two or more components sharing a
common center
.
Conicity: A tire irregularity
, which causes the tire to take
the shape of a cone when inflated and loaded. This may
generate a lateral force.
Contact Area: The total amount of tread surface that
contacts the road.
Cornering: The ease at which a vehicle travels a
cur
ved path.
Cross T
ube Assembly: Two tie rods and a tube, which
transfers the turning effort to the opposite side of the vehicle.
Curb Weight: The overall weight of a vehicle, less
passengers, luggage, or load.
Degree: A unit of measurement to describe an angle.
Dial Indicator: An instrument used to measure and display
linear displacement. Measurement is displayed on a dial face
and the scale is commonly graduated in thousandths.
Directional Stability: The tendency for a vehicle to
maintain a directed path.
Drag Link: A tube or rod used for interconnection between
Pitman Arm and tie-rod assemblies.
Dynamic Balance: This normally refers to the balance
condition of a wheel and tire assembly in motion.
Foot Pound: A unit of measurement used to describe
torque force.
Frame Angle: The angle formed by a horizontal line and a
line drawn parallel to the frame.
Geometric Centerline: A line drawn between the
midpoint of the front axle and the midpoint of the rear axle.
Horizontal: Parallel or level with the plane of the horizon.
Hub: The assembly that houses the bearings about which
the wheel and tire assembly rotates.
Hydraulic Pump: A power driven device generating
constant volume and pressure.
Included Angle: The sum of the angles, camber and SAI.
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