Dictionary of Automotive Terms Abbreviations

DICTIONARY OF AUTOMOTIVE TERMS - "Ar"

ARA: Acronym for Amsterdam-Rotterdam-Antwerp

Aramid fiber: A synthetic product used as a reinforcing agent in Brake linings. Aramid fiber has impressive wear properties.

Arbor

A rotating shaft in a lathe or drill.
Cylindrical or conical shaft on which a cutting tool or part to be machined is mounted.
The axis or shaft upon which a rotatable part is mounted the shaft upon which a gear or wheel is mounted.

Also see
Mandrel

Arc

The discharge of electric Current across a gap of two Electrodes. The term given to the flow of electricity through a gaseous space or air gap.
A welding term referring to the flow of electricity through the air which produces high temperatures.

Also see
Arc welding
Carbon Arc
Shielded arc
Short arc
Spray arc
Track arc

ARC

Acronym for Aeronautical Research Council in the UK.
Acronym for Ames Research Center in the USA
Acronym for Automatic Ride Control

Arc blow: A welding term referring to the tendency for an arc to wander or whip from its normal course during arc welding. It is caused by magnetic changes.

Arc crater

Depression formed in electrodes between which an electric arc has been maintained.
In arc welding, the depression which occurs in the weld metal.

Arc cutting: A welding term referring to making a kerf in a metal using the energy of an electric arc.

Arch: See
Fender arch
Flared wheel arch
Wheel arch Wing Arch

Arch extension: See
Wheel arch extension

Architectural acoustics: The study of how sound is transmitted and received in various parts of a building or even a vehicle, thus involves the placement of speakers.

Arch protector: See
Undershield

Arcing

The action of electricity when it leaps the gap between two Electrodes. Usually causes premature wear of breaker points.
Also see
Electrical Arcing
A faulty paint spraying technique where the spray gun is not moved along the panel surface at a uniform distance. Instead it is moved toward the panel when starting and moved away toward the end of the panel. The result of this technique is an uneven application of paint.
A process where the brake shoes are ground to the proper curvature for the drums they are to be used with. Modern brake shoes are pre-arced.

Arc Lamp: See
Automatic Arc Lamp

Arc of approach: The arc on the Pitch circle of a gearwheel over which two teeth are in contact while approaching the pitch point

Arc of contact: The arc on the Pitch circle of a gearwheel over which two teeth are in contact.

Arc of recess: The arc on the Pitch circle of a gearwheel over which two teeth are in contact while receding from the pitch point.

Arc process: See
Bredig's arc process

Arc-suppression coil

Arc suppressor: A device for automatically grounding the neutral point of an insulated-neutral transmission or distribution line if an arc to ground occurs. Also called arcing-ground suppressor

Arc welding: Welding by using an electric Current to melt both the metal to be welded and the welding rod or Electrode that is being added.

Also see
Automatic arc welding
Inert arc welding
Pulse arc welding

Area Cell: See
Active Area Cell

Arm: A part attached to or projecting from something.

Also see
A-arm
Actuator arm
Adjustable rocker arm
Ball joint rocker arm
Breaker arm
Branch
Check arm
Brush-holder arm
Contact arm
Control arm
Crankarm
Door check arm
Drop arm
Flex arm suspension
Forked rocker arm
High lift rocker arm
Idler arm
Knuckle arm
Lateral arm
Leading arm
Long and short arm suspension
Pitman arm
Radius arm
Rocker arm
Rocker arm cover
Rocker arm shaft
Rotor arm
Semi-trailing arm
Stay
Steering arm
Steering gear arm
Steering knuckle arm
Throttle arm
Tie rod arm
Torque arm
Track control arm
Trailing arm
Transverse arm

Armature

In a Relay, Regulator, Horn, etc., it is the movable part of the unit which indicates the presence of electric current as the agent of actuation.
Piece of low-reluctance ferromagnetic material (keeper) for temporarily bridging the poles of a permanent magnet, to reduce the leakage field and preserve magnetization.
In a Starter or Generator, it is the portion that revolves between the Pole shoes, made up of wire windings of copper on an iron Core or axle. When it revolves, an electric Current is induced.
Part of an electric motor, generator, or other device moved by magnetism

Also see
Bar-wound armature

Armature brake: A mechanical or electrical component in a starter used to stop the armature movement after the starter motor has been switched off.

Armature end plate: The end plate of a laminated armature core. It is of sufficient mechanical strength to enable the laminations to be clamped together tightly to prevent vibration. Also called Armature head

Armature head: See
Armature end plate

Armature reaction: The electrical current that flows in the armature winding of a DC motor tends to produce magnetic flux in addition to that produced by the field current. This effect, which reduces the torque capacity, is called armature reaction and can affect the commutation and the magnitude of the motor's generated voltage

Armature relay: A relay operated electromagnetically, thus causing the armature to be magnetically attracted.

Armature shaft: The primary shaft on which the armature is mounted in a starter or generator.

Armature winding: The complete assembly of conductors carried on the armature and connected to the commutator or to the terminals of the machine.

Arm cover: See
Rocker arm cover

Arme: See
Beton Arme

Armor plate: Traditionally, specially heavy alloy steel plate hardened on the surface; used for the protection of fighting vehicles and ships. There is also a form of armor plate based on aluminum alloy particularly suitable for fast moving military vehicles.

Armor-plated: Panels and glass that are extra thick to be bullet-proof.

Armour: British spelling of armor

Armrest: A projection upon which the occupants can rest or support their arms. Usually located on the door panel and sometimes in the center of the front seats or the center of the rear seat.

Arms: See
Bracket arms
Control arm
High lift rocker arms

Arm shaft: See
Rocker arm shaft

Armstrong: A colloquial term for manual steering. Without power assist, steering will need a strong arm, thus the name.

Armstrong-Siddeley: A vehicle brand of which the 1925-1948 models with required application are Classic cars.

Arm Stud: See
Notched Rocker Arm Stud

Arm suspension: See
Flex arm suspension
Long and short arm suspension
Semi-trailing arm suspension
Short Arm long Arm Suspension
Swing arm suspension

Arnolt: See
Arnolt Bristol

Arnolt Bristol: A vehicle brand of which the 1952-62 models are Milestone cars.

Aromatic Hydrocarbons: See
Polynuclear Aromatic Hydrocarbons

Aromatics: Hydrocarbons based on the ringed six-carbon benzene series or related organic groups. Benzene, toluene and xylene are the principal aromatics, commonly referred to as the BTX group. They represent one of the heaviest fractions in gasoline. They are called aromatics because many of their derivatives have sweet or aromatic odors.

Array: See
Binomial Array

Arrestance: See
Synthetic Dust Weight Arrestance

Arrester: A device which prevents a certain action. For example, a Spark arrester is a special pipe mounted in the end of the Exhaust pipe which prevents any burning gasses from coming out with the possible danger of igniting any combustibles in the area (i.e., setting the forest on fire).
Also see
Spark Arrester
Vibration Arrester

Arrive: The finish line of a Brevet or Randonnée.

ARS

Acronym for Air Ride Suspension -- a suspension system in which the load is supported on air-filled rubber bags rather than steel springs. The engine's air compressor fills the reservoir tanks which supplies air for the suspension and the air brake system.
Acronym for Automatic Restraint System

Articulated: Jointed. An articulated rod is made of two sections with a moveable Joint which permits its shape to go from perfectly straight to right angle.

Also see
Articulated bus
Articulated truck

Articulated bus: Articulated bus

A large bus with an accordion-like section in the middle of the body which allows the bus to turn sharply around corners as it articulates at that part of the bus.

Articulated mounting: A term used where parts are connected by links and links are anchored to provide a double hinging action.

Articulated Pistons: Two-piece pistons incorporating an entirely separate piston crown or dome with a separate skirt, and linking the two together with the piston pin. Many 1994 and later engines incorporate steel crown/aluminum skirt articulated pistons.

Articulated truck: A large truck with two sections to allow it to turn sharply around corners.

Articulation: See
Axle Articulation

Artificial aging: The method of speeding up the process of hardening by subjecting the substance (e.g., aluminum alloy) to a change in temperature or pressure.

Artificial antenna: An electrical unit which simulates an antenna without actually transmitting or receiving a signal. It is used to check or test radios and transmitters.

Artificial rubber: See
Synthetic rubber