DICTIONARY OF AUTOMOTIVE TERMS - "Ba"

b
  1. Symbol for susceptance in an AC circuit (unit is the siemens; measured by the negative of the reactive component of the admittance
  2. Symbol for magnetic flux density in a magnetic circuit (unit is the tesla; 1T=1 Wbm-2=1 Vsm-2).
B+
An acronym for Battery positive voltage used to designate positive voltage at aor near the battery level.
BA
An abbreviation for British Association which is a term used to describe a series of fine, small diameter threads for electrical and precision equipment.
Babbitt
An Alloy of tin, copper, and antimony having good antifriction properties. Used as a facing for bearings.
Also see
Babbitt metal
Babbitt's metal
A bearing alloy originally patented by Isaac Babbitt, composed of 50 parts tin, five antimony, and one copper. Addition of lead greatly extends range of service. Composition varies widely, with tin 5-90%, copper 1.5-6%, antimony 7-10%, lead 5-48.5%.
Babysitter
Colloquial term for a co-signer or co-buyer on an automobile purchase contract.
Babcock and Wilcox boiler
A water-tube boiler consisting in its simplest form of a horizontal drum from which is suspended a pair of headers carrying between them an inclined bank of straight tubes.
Babo's law
The vapor pressure of a liquid is lowered when a non-volatile substance is dissolved in it, by an amount proportional to the concentration of the solution.
Baby
A small incandescent spotlight used in film and television production.
Baby seat
Baby Seat

Baby Seat

A specially designed seating device (which is not generally standard equipment) to hold safely very young children (usually under the weight of 10 kilograms).
BAC
  1. Acronym for Blood Alcohol Content
  2. Acronym for bypass air control system
  3. Acronym for Bypass air control valve
Back
A large vat used in various industries, such as dyeing, soap-making, and brewing. Also spelled beck
Back ampere-turns
That part of the armature ampere-turns which produces a direct demagnetizing effect on the main poles. Also called demagnetizing ampere-turns
Back annealing
Controlling the softening of a fully work hardened metal so as to produce the desired degree of temper by partial recrystallization.
Also see
Back axle
The rear axle.
Back axle ratio
Back band
The outside member of a door or window casing.
Backbone
The major long-distance, multi-channel link in a telecommunication network, from which smaller links branch off
Also see
Backbone chassis
Backbone frame
Backbone Frame

Backbone Frame

A vehicle frame, having the cross-section of a rectangular box, that runs along the center of the vehicle and occupies the space between the seats.
  • This box generally divides at the front, running along each side of the gearbox and engine up to a crossmember to which the front suspension pieces are attached.
  • At the rear a similar triangular frame encloses the final-drive housing and provides attaching points for the rear suspension.
  • Lightness combined with high Torsional rigidity are features of this frame design, made famous by Colin Chapman with the Lotus Elan.

Backbone network
A high-capacity computer network that links together other networks of lower capacity. Fiber optic cables are often used to form these links.
Back coupling
Any form of coupling which permits the transfer of energy from the output circuit of an amplifier to its input circuit.
Also see
Back diode
Back edging
A method of cutting a tile or brick by chipping away the biscuit below the glazed face, the front itself being scribed.
Back EMF
The EMF which arises in an inductance (because of rate of change of current), in an electric motor (because of flux cutting) or in a primary cell (because of polarization), or in a secondary cell (when being charged). Also called counter EMF
Back-emf cells
Cells connected into an electric circuit in such a way that their emf opposes the flow of current in the circuit.
Back emission
Emission of electrons from the anode.
Back end
When the dealer sends a vehicle purchase contract to the bank for financing, the dealer is given an extra bonus (the back end) from the bank for choosing this bank.
Backfill
Materials used to replace previously excavated material.
Backfire
  1. Passage of unburned fuel mixture into the Exhaust system where it is ignited and causes an Explosion (backfire) prematurely.
  2. Sometimes Ignition takes place in the Intake manifold by a flame from a Cylinder because the Intake valve leaks. Burning of the fuel mixture in the Intake manifold may be caused by faulty Timing, crossed plug wires, leaky Intake valve, etc.
  3. A welding term referring to a short pop of the torch flame followed by extinguishing of the flame or continued burning of the gasses.
Backfiring
Repeated backfires in the exhaust or the cylinders.
Backfitting
Making changes to nuclear (and other) plants already designed or built, e.g., to cater to changes in safety criteria.
Back-flap hinge
A hinge in two square leaves, screwed to the face of a door which is too thin to permit the use of a butt hinge.
Backflow scavenging
Backflushing
Pushing fluid in a direction opposite of normal flow. This is done for cleaning the engine's cooling system.
Back focus
The distance between the rear surface of a lens and the image of an object at infinity.
Back gear
A speed-reducing gear fitted to the headstock of a belt-driven metal-turning lathe. It consists of a simple layshaft, which may be brought into gear with the coned pulley and mandrel when required.
Background
Extraneous signals arising from any cause which might be confused with the required measurements, e.g., in electrical measurements of nuclear phenomena and of radioactivity, it would include counts emanating from amplifier noise, cosmic rays and insulator leakage.
Background job
A task having a low priority within a multiprogramming system.
Also see
Background noise
Extraneous noise contaminating sound measurements and which cannot be separated from wanted signals. For example residual output from microphones, pickups, lines giving a signal-to-noise ratio. Also called ground noise
Background radiation
Radiation coming from sources other than that being observed.
Background video
(BGV) A technique for overlaying video on previously recorded depth multiplex audio. Also called video on sound (VOS).
Backhand welding
Welding in the direction opposite to the direction that the gas flame is pointing. Also called backward welding.
Back Haul
  1. After an outbound shipment has been delivered, the truck will return empty. In order to generate more revenue, the dispatcher may find a shipment for the return which is the back haul.
  2. Movement in the direction of lighter traffic flow when traffic generally is heavier in the opposite direction.
  3. To move a shipment back over part of a route already traveled.
Backheating
Excess heating of a cathode due to bombardment by high-energy electrons returning to the cathode. In magnetrons, it may be sufficient to keep the cathode at operating temperature without external heating.
Backing
  1. Some material placed on the root side of a weld to aid control of penetration.
  2. Light-absorbent layer on the rear surface of photographic film or plate to reduce unwanted exposure
  3. A meterological term describing the changing of a wind in a counter-clockwise direction.
    Also see
Also see
Backing boards
Wedge-shaped wooden boards between which an unbound book is held in the lyingpress, while the joints are being formed for attaching the case.
Backing pad
A rubber disc which is secured to a spindle which in turn is attached to a drill or other tool which rotates the spindle. An abrasive disc or polishing disc is secured to the backing pad.
Backing plate
Backing plate

Backing plate

  1. The part of a drum brake to which the wheel cylinder(s) and the brake shoes are attached.
  2. A pressed steel plate upon which the brake shoes, wheel cylinder, and anchor pin are mounted.

Backing-up
  1. Printing on the second side of a sheet.
  2. Backing a letterpress printing plate to required height.
Back-kick
The violent reversal of an internal-combustion engine during starting due to a Backfire
Backlash
  1. The amount of play or Clearance between two parts. In the case of gears, it refers to how much one gear can be moved back and forth without moving the gear into which it is meshed.
  2. Mechanical deficiency in a tuning control, with a difference in dial reading between clockwise and counterclockwise rotation.
  3. Property of most regenerative and oscillator circuits, by which oscillation is maintained with a smaller positive feedback than is required for inception.
Backlight
  1. The rear window of a vehicle. Most people call it a rear window and erroneously think of backlight as the taillight.
  2. The light source (often a cold cathode discharge in a flat fluorescent envelope) used in some light-modulating flat panel displays such as those based on LCD
Backlight compensation
(BLC) The opening of the iris to correctly expose a backlit subject which would otherwise be a silhouette
Backlight defogging system
Heated rear window
Backlight heater
Heated rear window
Back lighting
Lighting illuminating the subject from behind, opposite the camera, often to provide rim light or halo effects.
Back lobe
Lobe of polar diagram for antenna, microphone, etc. which points in the reverse direction to that required.
Backlocking
Holding a signal lever partially restored until completion of a predetermined sequence of operation.
Backmatter
The items which follow the main text of a book, i.e., appendices, notes, glossary, bibliography, index. The UK term is end matter
Back observation
An observation made with instrument on station just left. Also called back sight
Back panel
The panel of the body shell set underneath the trunk lid. It is sometimes referred to as the rear valance if the area below the trunk lid consists of only a single panel that extends down to the bottom of the body; in many designs, however, the rear valance is a separate horizontal panel that extends from the rear bumper area downward. The British term is rear panel
Backplate
British term for Brake backing plate
Back-porch effect
The prolonging of the collector current in a transistor for a brief time after the input signal (particularly if large) has decreased to zero.
Back pressure
  1. The Resistance to the flow of Exhaust gases through the Exhaust system. By rerouting the exhaust gases for noise suppression, a Muffler causes back pressure, but a straight pipe alone causes only minimal back pressure. Some engines require back pressure, so that removing the Exhaust system will cause internal damage.
  2. Pressure in low side of refrigerating systems; also called suction pressure or low-side pressure.
  3. The pressure opposing the motion of the piston of an engine on its exhaust stroke.
  4. The exhaust pressure of a turbine. Increased by clogged or defective exhaust system.
  5. Pressure against which a fluid or gas is flowing, resulting from friction in lines, restrictions in pipes, valves, pressure in vessel to which fluid is flowing, hydrostatic head, or other impediment that causes resistance to fluid flow.
Back pressure modulated
Back pressure modulated valve
Backpressure Transducer EGR Valve
Back Pressure Transducer Valve
Back-pressure turbine
A steam turbine from which the whole of the exhaust steam, at a suitable pressure, is taken for heating purposes.
Back pressure valve
Backpressure variable transducer
(BVT) a system combining a ported EGR valve and a backpressure variable Transducer to control emissions of NOx
Back projection
  1. Projection of a picture, from film, transparency, or video, on to a translucent screen to be viewed from the opposite side,
  2. A form of motion picture composite photography in which the projected picture forms the background to action taking place in front of it, both being photographed together.
Back rake
In a lathe tool, the inclination of the top surface or face to a plane parallel to the base of the tool.
Backrest
The back (upright) part of the seat against which your back reclines.
Back scatter
The deflection of radiation or particles by scattering through angles greater than 90° with reference to the original direction of travel.
Back-seat
  1. An air conditioning term which means to rotate a service valve counterclockwise all the way down until the valve is back-seated. When referring to a stem type service valve, the term has a more specific meaning-in the back-seated position, the valve outlet to the system is open and the service port in the valve is closed (its normal operating position).
  2. The seating behind the front passenger and/or driver
Back-seat driver
A person who is not physically in control of the vehicle, but who gives driving instruction to the driver, usually in an obnoxious manner.
Back seating
Fluid opening or closing such as a gauge opening to seat the joint where the valve stem goes through the valve body.
Back sight
Backspacing
Process which maintains synchronization when video recording is stopped and started. The tape being rolled back for roughly one second at the end of a recorded segment then switched into play to compare and synchronize the control track pulses with the incoming synchronization pulses before recording begins again.
Back-step welding
Welding small sections of a joint in a direction opposite the direction that the weld as a whole is progressing.
Backstop
The structure of a relay which limits the travel of the armature away from the pole-piece or core.
Back-to-back
Parallel connection of valves, with the anode of one connected to the cathode of the other, or transistors in parallel in opposite directions, to allow control of AC current without rectification.
Back up
To go in reverse.
Back up alarm
An annoying loud beeping which is repeatedly sounded when a vehicle (usually a large truck) is placed in reverse. It is designed to warn pedestrians behind the vehicle. The British term is reversing warning signal
Back up light
A white light which is located at the rear of the vehicle and is illuminated when the transmission is placed in reverse. The British term is reversing light
Back-voltage
Voltage which opposes the current when the current in an inductive circuit changes and the magnetic field cuts the conductors.
Backward busying
Applying busy condition at the incoming end of a trunk or junction (usually during testing or fault-clearance) to indicate at outgoing end that circuit must not be used.
Backward diode
One with characteristic of reverse shape to normal. Also called AU diode or back diode
Backward hold
A method of interlocking the links of a switching chain by originating a locking condition in the final link and extending it successively backwards to each of the preceding links
Backward lead
Backward shift
Movement of the brushes of a commutating machine around the commutator, from the neutral position, and in a direction opposite to that of the rotation of the commutator, so that the brushes short-circuit zero emf conductors when the load current, through armature reaction, results in a rotation of the neutral axis of the air-gap flux. Shifting the brushes in this way reduces sparking on the commutator. Also called backward lead
Backward signaling
Signaling from the called to the calling end of a circuit.
Backward-wave tube
General term for a family of microwave traveling-wave tubes in which energy on a slow-wave circuit or structure, linked closely to the electron beam, flows in the opposite direction to the electrons. They can be used as stable, low-noise amplifiers or as oscillators, as the latter, they can be easily tuned over a wide frequency range by altering he beam voltage.
Backward welding
Backwater
Water, containing fine fibers, loading and other additives, removed in the forming section of a paper or board-making machine. It is generally re-used within the system or clarified in a saveall to recover suspended matter.
Backyard mechanic
A person, whether qualified or not, who repairs his own vehicle or those of others and works in his own property.
BAC level
Acronym for Blood Alcohol Content level
Badge
An emblem with a manufacturer's name and/or logo on a plate to identify a model or component.
Badge engineering
When a manufacturer sells two identical vehicles but the model names are different, he is badge engineering. For example, General Motors may sell a vehicle as a Chevrolet or a Pontiac where the only difference is the model name, logo, and more or less chrome or other minor alterations.
Badging
The act of a manufacturer in Badge engineering
Baffle
Baffle

Baffle

  1. An obstruction (e.g., plate or vane) used to slow down or divert the flow of gases, liquids, sound, etc. They are found in the Fuel tank, Crankcase, Muffler, and Radiator.
  2. Extended surface surrounding a diaphragm of a sound source (loudspeaker) so that an acoustic short-circuit is prevented.
  3. Any device to impede or divide a fluid flow in a tank to reduce sloshing of liquid.
  4. Plates fitted between cylinders of air-cooled engines to assist cooling.
  5. Internal structure or electrode, with no external connection, used in gas-filled tubes to control the discharge or its decay.
  6. An object placed in an Appliance to change the direction of or retard the flow of gas, air, gas-air mixtures, or flue (exhaust) gases.
  7. A wall or partition inside a liquid tank that inhibits the flow of fluids reducing the slosh effect that liquid tankers experience.

Baffle loudspeaker
An open-diaphragm loudspeaker, in which the radiation of sound power is enhanced by surrounding it with a large plane baffle, generally of wood.
Baffle plate
  1. A metal plate that acts as a Baffle.
  2. A plate used to prevent the movement of a fluid in the direction which it would normally follow, and to direct it into the desired path.
  3. Plate inserted into waveguide to produce change in mode of transmission.
Bag
Bag drop
A location where your supplies have been cached. In randonneuring events of 1200 km, you can pre-arrange to have a bag of extra clothes and other supplies waiting for you at a prescribed control (i.e., checkpoint). Also called a drop.
Bagger
A motorcycle equipped with saddlebags and other touring amenities.
Bag molding
Use of a flexible membrane (the bag) to exert pressure, usually about one atmosphere, on a thermosetting composite laminate or sandwich component while it is curing at ambient temperature in an open mold. Pressure can be generated either by evacuating the inside of the bag (vacuum bag molding) or by pressurizing its outer surface (pressure bag molding).
Bag pump
A form of bellows pump, in which the valved disk taking the place of the bucket is connected to the base of the barrel by an elastic bag, distended at intervals by rings.
Bail
The spring-wire loop used to secure the cover on most Master cylinder reservoirs.
Bailey bridge
A temporary bridge made by assembling portable prefabricated panels. A nose is projected over rollers across the stream, being followed by the bridge proper, with roadway. Also used over pontoons.
Baily furnace
An electric-resistance furnace in which the resistance material is crushed coke placed between carbon electrodes; used for heating ingots and bars in rolling mills, for annealing, etc.
Bainite
A microstructural product formed in steels when cooled from the austenite state at rates or transformation temperatures intermediate between those which form pearlite martensite, i.e., between about 800 and 500° K. It is an acicular structure of supersaturated ferrite containing particles of carbide, the dispersions of the latter depending on the formation temperature. Its hardness is intermediate between that of pearlite and martensite and exhibits mechanical properties similar to those of tempered martensite in a steel of the same carbon content.
Bait
Baize
A lightweight woollen felt used to cover pool tables and bulletin boards.
Bake
A process of drying or curing paint by using heat.
Baked core
A dry sand core baked in the oven to render it hard and to fix its shape.
Also see
Baked images
The technique of heating a printing plate (mainly lithographic) to harden the printing image and thus increase the image's resistance to wear, hence lengthening the run expectancy on the press.
Bakelite
The trademark for a synthetic thermosetting plastic Resin used in electrical parts because it is a good insulator. The name comes from its inventor, L. H. Baekeland, 1863-1944.
Bakeoff
A term borrowed from food contests where a manufacturer's design teams compete by displaying their clay model proposals for evaluation.
Bake-out
Preliminary heating of components of a vacuum device to release absorbed gases.
Baking finish
Paint that requires baking in order to dry.
Baking temperature
The temperature at which a varnish or paint must be baked to develop desired final properties of strength and hardness.
Balance
  1. The state in which weight is evenly distributed.
  2. The action of applying weights or drilling holes in something to establish even weight distribution so that vibration is reduced.
  3. Adjustment of sources of sound in studios so that the final transmission adheres to an artistic standard.
  4. Said to be obtained in bridge measurements when the various impedances forming the arms of the bridge have been adjusted, so that no current flows through the detector.
Balance bar
The heavy beam by which a canal-lock gate may be swung on its Pintle, and which partially balances the outer end of the gate.
Balance box
A box, filled with heavy material, used to counterbalance the weight of the jib and load of a crane of the cantilever type.
Balance control
A switching device on a stereo radio which adjusts the amount of sound coming from the left and right speakers or from the front and rear speakers.
Balance-crane
A crane with two arms, one having counterpoise arrangements to balance the load taken by the other.
Balanced amplifier
One in which there are two identical signal-handling branches operating in phase opposition, with input and output connections balanced to ground.
Balanced-armature pick-up
A pick-up in which the reproducing needle is held by a screw in a magnetic arm, which is pivoted so that its motion diverts magnetic flux from one arm of a magnetic circuit to another, thereby inducing emf in coils on these arms.
Balanced circuit
For AC and DC, a circuit which is balanced to ground potential, i.e., the two conductors are at equal and opposite potentials with reference to ground at every instant.
Balanced crankshaft
A crankshaft with extended reinforcements to form counterbalancing or act as a vibration damper.
Balanced current
A term used, in connection with polyphase circuits, to denote currents which are equal to all the phases. Also applied to DC three-wire systems.
Balanced draft
A system of air-supply to a boiler furnace, in which one fan forces air through the grate, while a second, situated in the uptake, exhausts the flue gases. The pressure in the furnace is thus kept atmospheric, i.e., is balanced.
Balanced draught
A system of air-supply to a boiler furnace, in which one fan forces air through the grate, while a second, situated in the uptake, exhausts the flue gases. The pressure in the furnace is thus kept atmospheric, i.e., is balanced.
Balanced engine
An engine in which all the reciprocating parts such as pistons and connecting rods are adjusted to exactly the same weight.
Balance disc
A disc-shaped device in a centrifugal pump which is attached to the pump shaft. The disc lifts when a force is applied to the underside of the disc allowing pressure to leak past until the axial forces are balanced.
Balanced laminate
Symmetrical laminated material in which the sequence of laminae above the center plane is the mirror image of that below it.
Balanced line
A line in which the impedances to ground of the two conductors are, or are made to be, equal. Also called balanced system
Balanced load
A load connected to a polyphase system, or to a single-phase or DC three-wire system, in such a way that the currents taken from each phase, or from each side of the system, are equal and at equal power factors.
Balanced mixer
A mixer, which may be made of discrete components or formed in stripline or waveguide, in which the local oscillator breakthrough in the output is minimized and certain harmonics suppressed. The contribution of local oscillator noise to the receiver's overall performance is also reduced by such a mixer.
Balanced modulator
A modulator in which the carrier and modulating signal are combined in such a way that the output contains the two sidebands but not the carrier. Used in color television to modulate subcarriers, and in suppressed-carrier communication systems.
Balanced network
A network arranged for insertion into a Balanced circuit and therefore symmetrical electrically about the mid-points of its input and output pairs of terminals.
Balanced-pair cable
A cable with two conductors forming a loop circuit, the wires being electrically balanced to each other and ground (shield), e.g., an open-wire antenna feeder.
Balanced pedal
In an organ console, the foot-operated plate, pivoted so that it stays in any position, for remote control of the shutter of the chambers in which ranks of organ pipes are situated; it also serves for bringing in all the stops in a graded series.
Balanced protective system
A form of protective system for electric transmission lines and now widely used domestically in which the current entering the line or apparatus is balanced against that leaving it. Any fault, such as a short circuit to ground, upsets this balance and energizes a relay which trips the faulty circuit. Also called differential protective system or colloquially, ground leak relay or ground trip.
Balanced system
Balanced terminator
A two-terminal load in which both terminals present the same impedance to ground.
Balanced voltage
A term used, in connection with polyphase circuits, to denote voltage which are equal to all the phases. Also applied to DC three-wire systems.
Balanced weave
A weave in which the length of free yarn between the intersections is the same as the warp and weft directions and on both sides of the fabric.
Balance gate
A flood gate which revolves about a vertical shaft near its center, and which may be made either self-opening or self-closing as the current sets in or out by giving a preponderating area to one leaf of the gate.
Balance patch
A factory installed patch used to bring a new tire within quality control balance tolerances before distribution and sale. It is placed inside the Tire casing and looks much like a nail hole repair patch.
Balance pipe
A tube which joins two or more carburetors to even out the flow difference.
Balance piston
Balancer
A device used on polyphase or three-wire systems to equalize the voltages between the phases or the sides of the system, when unbalanced loads are being delivered.
Balancer transformer
An autotransformer connected across the outer conductors of an ac three-wire system, the neutral wire being connected to an intermediate tapping.
Balance shaft
An engine will normally vibrate because of the up-and-down motion of the Pistons which turn a Crankshaft in one direction. A balance shaft rotates (often in the opposite direction) so that its vibration cancels some of the vibration of the engine. Sometimes an engine will have two balance shafts turning in opposite directions located on either side of the Crankshaft.
Balance valve
Balance weight
  1. A lead weight attached to the rim of a wheel.
  2. Small weights threaded on radial arms on the movement of an indicating instrument, so adjusted that the pointer gives the same indication whatever the orientation of the instrument.
  3. A weight used to counterbalance some part of a machine, e.g., weights applied to a crankshaft to minimize or neutralize the inertia forces due to reciprocating and rotating masses of the engine.
    Also see
Balancing
  1. Dismantling engine and reassembling it to exact Specifications and Tolerances. This process may help to improve engine performance, smoothness, and reliability. Sometimes called Blueprinting.
    Also see
  2. Keeping wheels in balance.
  3. In color reproduction, control of the levels of the three color components to achieve a satisfactory picture without obvious color bias, esp. in the representation of neutral grey tones.
  4. The process of adjusting a traverse, i.e., applying corrections to the different survey lines and bearings so as to eliminate the closing error.
Balancing antenna
Auxiliary reception antenna which responds to interfering but not to the wanted signals. The interfering signals thus picked up are balanced against those picked up by the main antenna, leaving signals more free from interference.
Balancing machine
A machine for testing the extent to which a revolving part is out of balance, and to determine the weight and position of the masses to be added, or removed, to obtain balance.
Also see
Balancing speed
Balancing weight
Bald tire
A tire on which the tread is all worn away. A Slick also has no tread, but this is done deliberately for racing purposes.
Balk
The material between two excavations. Also called baulk.
Balking
Balk ring
Balk ring

Click image to supersize
Balk Ring

A friction-regulated Pawl or plunger used to make the engagement of gears easier. British spelling is baulk ring
Ball
  1. A sphere usually made of metal when used in automotive applications.
  2. A US highway traffic engineering term for a circular traffic light in green, amber, or red.
Ball and nut
Ball-and-nut steering
Ball and socket
Ball-and-socket head
Camera mounting allowing universal movement in rotation and tilt before fixing by clamping usually fitted to the top of tripod.
Ball-and-socket joint
A joint between two rods, permitting considerable relative angular movement in any plane. A ball formed on the end of one rod is embraced by a spherical cup on the other. Used in light control systems (e.g., in connecting a pair of bell-cranks which operate in planes at right angles) and in the steering mechanism of motor vehicles, in which both ball and cups are of case-hardened metals. Heavier examples allow a large base plate to be placed under a supporting column in a jack-up pontoon or modified as bridge bearings to allow some articulation.
Also see
Ball and spring
Ballast
  1. Any liquid or solid weight (gravel, stone, or metal) placed in a ship to change the trim, increase the draft, or to regulate the stability.
  2. A layer of broken stone, gravel, or other material deposited above the formation level of road or railway; it serves as foundation for road-metal or permanent-way respectively.
  3. Sandy gravel used as a coarse aggregate in making concrete.
Ballast ignition system
An ignition system which uses a Ballast resistor connected in series with the coil primary winding and which is bypassed when the starter is engaged so that the spark is more efficient under cold weather starting.
Ballasting
The addition of Liquid or Dry weight inside the tire to act as a counterbalance, to increase traction, reduce wheel spin, and dampen out bounce.
Ballast lamp
Normal incandescent lamp used as a ballast resistor, current limiter, alarm, or to stabilize a discharge lamp.
Ballast resistance
A term used in railway signaling to denote the resistance between the two track rails across the Ballast on which the track is laid. If allowed to fall too low, it will have the effect of shunting the signal from a trains's wheels.
Ballast resistor
(BAL RES)
  1. A resistor inserted into a circuit to swamp or compensate changes, e.g., those arising through temperature fluctuations. One similarly used to swamp the negative resistance of an arc or gas discharge. Also called ballast tube.
  2. A Resistor constructed of a special type wire, the properties of which tend to increase or decrease the Voltage in direct proportion to the heat of the wire.
Also see
Ballast tank
Water-tight containers at the bottom or sides of a ship which are filled with seawater for ballasting purpose.
Ballast tube
Ball bearing
An antifriction bearing consisting of an inner and outer Hardened steel Race (or Cage) separated by a series of hardened steel balls.
Ball bearing puller
A tool for removing a ball bearing from a shaft or from a housing.
Ball cage
A circular frame which holds the balls in place in a ball bearing.
Ball check valve
Valve assembly which permits flow of fluid in one direction only.
Ball-ended magnet
A permanent magnet, consisting of a steel wire with a steel ball attached to each end; this gives a close approximation to a unit pole.
Ball end hexagon screwdriver
A tool that looks like an Allen wrench except it has a small ball at the very end. This arrangement allows it to work at various angles.
Balling
  1. A process that occurs in the cementite constituent of steels on prolonged annealing at 650°C - 700°C.
  2. The operation of forming balls in a puddling furnace.
Ballistic circuit breaker
A very high-speed circuit breaker, in which the pressure produced by the fusing of an enclosed wire causes interruption of the circuit.
Ballistic galvanometer
A galvanometer with a long swing period; the deflection measures the electric charge in a current pulse or the time integral of a voltage pulse.
Ballistic method
A method of high-grade testing used in electrical engineering, a Ballistic galvanometer being used.
Ballistic pendulum
A heavy block suspended by strings so that its swings are restricted to one plane. If a bullet is fired into the block, the velocity of the bullet may be calculated from a measurement of the angle of swing of the pendulum.
Ballistics
The study of the dynamics of the path taken by an object moving under the influence of a gravitational field.
Ball joint
Ball Joint

Ball Joint

A flexible Joint using a ball and Socket type of construction, used in Steering linkage setups, Steering knuckle pivot supports, etc. Their flexibility helps to compensate for the changes in the wheel and steering when turning or hitting a bump on the road. There are usually upper and lower ball joints attached to the upper and lower A-arms. Some have a grease nipple to allow periodic lubrication.
Ball joint rocker arm
Ball Joint Rocker Arm

Ball Joint Rocker Arm

A Rocker arm used by GM that is mounted upon a ball-shaped device on the end of a Stud instead of being mounted around a shaft.
Ball joint separator
A tool for forcing out ball or tapered joints. One style is shaped like a two-prong fork with a wedge-shaped jaw which is struck with a hammer to separate the joint. Another style uses direct pressure from a screw or screw-activated lever action to split the joint.
Ball joint steering knuckle
Steering Knuckle

Steering Knuckle

A Steering knuckle that pivots on Ball joints instead of on a Kingpin.
Ballonet
An air compartment in the envelope of an aerostat, used to adjust changes of volume in the filler gas.
Balloon
A general term for aircraft supported by buoyancy and not driven mechanically.
Balloon barrage
An anti-aircraft device consisting of suitably disposed tethered balloons
Balloon former
On rotary presses, an additional former mounted above the others, from which folded webs are gathered to make up the sections of multi-sectioned newspapers or magazines.
Ballooning of yarn
The shape taken up by yarns on the spinning or doubling machines.
Balloon tire
A type of low pressure tire which was first introduced in the 1920s. Its width and height were the same which gave it a rounded shape. This style was used on bicycles as well as automobiles.
Ballot
A vehicle brand of which the 2LS, 2LT, 2LTS, RH, RH2, and RH3 models with required application are classic cars.
Ballotini
Small, solid glass spheres or beads used as a filler for plastics and to increase reflectivity in paints and printing inks.
Ball-pane hammer
A fitter's hammer, the head of which has a flat face at one end, and a smaller hemi-spherical face or pane at the other; used chiefly in riveting. Also called Ball pien hammer
Ball pien hammer
Ball Pein Hammer

Ball Pein Hammer

A hammer with two ends on the head. One is round and the other is flat. They are best used for hammering and shaping metal. Also spelled ball peen
Ball peen hammer
A hammer with two ends on the head. One is round and the other is flat. They are best used for hammering and shaping metal. Also spelled ball pien
Ball race
  1. The inner or outer steel ring forming one of the ball tracks of a ball bearing.
  2. Commonly, the complete ball bearing
Ball sizing
Forcing a suitable ball through a hole to finish size it, usually part of a Broach with a series of spherical lands of increasing size arranged along it.
Ball socket
A recessed spherical well for receiving the ball in a Ball joint
Ball steering
Ball track
Ball universal
Ball universal joint
Ball valve
A check valve in which a ball in a tube is used to control the flow of liquid.
Ball worm
Ball worm and nut
BALPA
Acronym for British Airline Pilots Association
BAL RES
Abbreviation for Ballast resistor
Bambi
Trucker slang for a deer (dead or alive) as in "There's a Bambi on the side at the 43 yardstick."
Banana
Banana

Banana

A colloquial term for the opening between the top of the steering-wheel rim and the hub through which the driver can see the instrument panel.
Banana plug
A single conductor plug which has a spring metal tip, in the shape of a banana. The corresponding socket or jack is termed a banana jack
Banbury mixer
Type of machine used for compounding rubber with vulcanizing ingredients and carbon black.
Band
Bands are like a metal belt which is in the shape of a circle where the two ends are close, but do not meet. They wrap around parts inside the Transmission called drums. The drums house the gears and Clutches and Freewheel until a certain gear needs to be applied. When first gear needs to be applied, the drum for first gear is locked up by the application of the band. By locking up the drum, the gears now drive the wheels rather than Freewheel inside the drum.
Band brake
A flexible band wrapped partially around the periphery of a wheel or drum. One end is anchored, and the braking force is applied to the other.
Also see
Band chain
Steel tape. More accurate than ordinary chain.
Band clutch
A Friction clutch in which a fabric-lined steel band is contracted on to the periphery of the driving member by engaging gear.
Band conveyor
An endless band passing over, and driven by, horizontal pulleys, thus forming a moving track which is used to convey loose material or small articles. Also called belt conveyor or conveyor belt
Band edge energy
The energy of the edge of the conduction band or valence band in a solid, measured with respect to some convenient reference or else used as the reference level for other energy states.
Band gap
The range of energies which correspond with those values which are forbidden for delocalized states, according to the Band theory of solids. Localized states such as those associated with ionized dopants, impurity atoms, or crystal imperfections exist in the gap. The generation of pairs of electrons and holes requires quanta of at least the energy of the band gap. Direct recombination likewise furnishes quanta with energies at least equal to the band gap.
Band ignitor tube
A valve of mercury pool type in which the control electrode is a metal band outside the glass envelope. Also called capacitron
Banding
  1. A structural feature of wrought metallic materials revealed by etching, resulting from microstructural segregates and constitutional differences within the grain structure becoming drawn out in the direction of working.
  2. Defect in videotape recording heads causing visible horizontal bands in the picture.
  3. A plastic or metal strapping used to secure a product to a pallet or skid.
Banding machine
A device used to surround a metal band around freight or secure it to a pallet.
Band-pass filter
Filter which freely passes currents having frequencies within specified nominal limits, and highly attenuates currents with frequencies outside these limits.
Band radio
Band-rejection filter
Bands
See
Bandsaw
A narrow endless strip of saw-blading running over and driven by pulleys, as a belt; the strip passes a work table placed normal to the straight part of the blade. The workpiece is forced against the blade and intricate shapes can be cut. Also used for cutting animal carcases in butchery.
Band spectrum
Molecular optical spectrum consisting of numerous very closely spaced lines which are spread through a limited band of frequencies.
Band-spreading
  1. Use of a relatively small tuning capacitor in parallel with the main tuning capacitor of a radio receiver, so that fine tuning control can be done with the smaller; useful when the frequency band is crowded.
  2. Mechanical means, like reduction gearing, to achieve the same result.
Band-stop filter
Filter which attenuates signals having frequencies within a certain range or band, while freely passing those outside this range. Also called band-rejection filter
Band theory of solids
For atoms brought together to form a crystalline solid, their outermost electrons are influenced by a periodic potential function, so that their possible energies form bands of allowed values separated by bands of forbidden values (in contrast to the discrete energy states of an isolated atom). These electrons are not localized or associated with any particular atom in the solid. This band structure is of fundamental importance in explaining the properties of metals, semiconductors, and insulators.
Bandwidth
  1. The range of audio frequencies that an audio component (radio) can handle.
  2. The width, or spread, of the range of frequencies used for a given purpose, e.g., the width of individual channels allotted to speech or to television transmissions.
  3. The space occupied in the frequency domain by signals of a specified nature, e.g., telephone quality speech, broadcast-quality stereophonic music, television, radar transmission, etc.
B & S
Abbreviation for Bore and Stroke which describes the width of a cylinder hole and the distance that the piston moves each time.
B & S gage
Abbreviation for Brown and Sharpe. A standard measure of wire diameter.
B & S gauge
Abbreviation for Brown and Sharpe. A standard measure of wire diameter.
Banger
  1. A colloquial term used to express the Cylinders in an engine. Often used with a number such as Six banger.
  2. A British colloquial term for Beater (an older, cheaper, well-worn car which is still usable).
  3. One who fakes an accident.
    Also see
Banger racing
A competition of speed on small racing tracks where older cars are driven as fast as they can go and where bumping other racing cars is permitted (encouraged??).
Banging
Banjo
  1. Besides being a musical instrument, this is a Fitting which is shaped like a banjo. It has round end that is doughnut shaped with a tube coming out from one side. It is usually used to transfer fluid from the center hole of the round end and out the lateral tube.
  2. A drum-shaped central part of an axle casing containing the differential.
Banjo axle
The commonest form of rear-axle casing in which the provision of the differential casing in the center produces a resemblance to a banjo with two necks.
Banjo fitting
A type of hydraulic fitting, shaped like a banjo, through which a hollow bolt passes, allowing fluid transfer from a hydraulic line to a hydraulic component.
Banjo rear axle housing
A rear axle housing from which the Differential unit may be removed while the housing remains in place on the vehicle. The housing is solid from side to side. Compare Split rear axle housing
Bank
A number of similar pieces of equipment grouped in line and connected, e.g., a bank of engine cylinders, coke ovens, or transformers.
Also see
Banked boiler
A boiler furnace in which the rate of combustion is purposely reduced to a very low rate for a period during which the demand for steam has ceased by e.g., covering the fire with slack or fine coal or banking up. Also called banked fire.
Banked fire
Banking
  1. The slope of a track from the wall to the Apron, generally measured in the corners.
  2. Angular displacement of the wings of an aircraft about the longitudinal axis, to assist turning. In other words, tipping the plane so that one wing drops while the other rises.
  3. Process of suspending operation in a smelter by feeding fuel into the furnace only until as much metal and slag as possible have been removed, after which all air inlets are closed.
Banquette
  1. A raised footway inside a bridge parapet.
  2. A ledge on the face of a cutting.
Also see
Baquet
French for bath tub to describe an old vehicle with two rows of seats, no doors, roof, or windshield. Also called touring car
Also see
Bar
  1. A unit of pressure. One bar equals 100 kilopascals (10 5Pa) or 750.07mm of mercury at 0°C and latitude 45° or about 14.5 psi.
  2. A rod.
  3. A pivoted bar, parallel to a running rail, which being depressed by the wheels of a train, is capable of holding points or giving information about a train's position
  4. Material of uniform cross-section, which may be cast, rolled, or extruded.
Barach
The author and compiler of this dictionary at Motorera.com
Bar-and-yoke
Method of magnetic testing in which the sample is in the form of a bar, clamped into a yoke of relatively large cross-section, which forms a low reluctance return path for the flux.
Barathea
Woven fabric used for coats and suits and made from silk, worsted, or man-made fibers. Characteristic surface appearance arising from the twill or broken-rib weave used in its manufacture.
Barba's law
Law concerned with the plastic deformation of metal test pieces when strained to fracture in a tensile test; it states that test pieces of identical size deform in a similar manner.
Barbershop
Trucker slang for a low overpass where a large truck might clip its top if the truck's clearance is higher than the height of the overpass.
Barchetta
An old style streamlined sports car devoted to racing. Distinctive because it had no doors or roof; but had either one or two separate seats. The name was also adopted by Fiat, Maserati, Lamborghini, Ferrari, Alfa Romeo, and other manufactuers of modern sports cars
Bar clamp
Bar Clamp

Bar Clamp

A tool with a stationary head and a sliding foot for clamping purposes.
Bar Code
UPC markings of a series of black bars that identify a product. The code can be scanned to reveal its unique part number for more efficient entry into a computer database.
Bare
  1. Something slightly smaller than the specified dimension.
  2. A unit without the attaching hardware
Bare conductor
A conductor not continuously covered with insulation, but supported intermittently by insulators, e.g., bus-bars and overhead lines.
Bare electrodes
Electrodes used in welding that are not coated with a basic slag-forming substance.
Bar ends
Bar Ends

Bar Ends

Short handlebar Add-on extensions which are attached to the ends of a Mountain bike handlebar to add another riding position.
Bar end shifter
Bar End Shifter

Bar End Shifter

A bicycle gear shifter that is inserted into each of the ends of a handlebar.
Bare pavement
A road condition where the pavement is visible and substantially free of snow and ice following plowing, scraping, or other means
Bare shell
The shell of a car body in which all parts have been removed including doors, hood, and trunk lid.
Barge
A flat-bottomed boat for carrying cargo or bunker oil, usually pulled by tugs.
Also see
Barge carriers
Ships designed to carry barges.
Bar generator
Source of pulse signals, giving a bar pattern for testing TV cathode-ray tubes.
Bar keel
See
Barkhausen effect
The phenomenon of discontinuous changes in the magnetization of a magnetic material while the magnetizing field is smoothly varied. It is the consequence of sudden changes in the domain structure as domain walls overcome various pinning defects and to a lesser extent as domain orientations discontinuously rotate away from preferred crystal areas H. G. Barkhausen (in 1919) detected voltage pulses induced in coils surrounding a magnetic sample as it was magnetized. Analogous ultrasonic emissions are also associated with the magnetization of magnetostrictive materials. The character of Barkhausen emissions is strongly dependent on microstructure and stress.
Barkhause-Kurz oscillator
Oscillator with a triode valve having its grid more positive than the anode. Electrons oscillate about the grid before reaching the anode. Output frequency depends on the transit time of electrons through the tube.
Bar lathe
A small lathe of which the bed consists of a single bar of circular, triangular, or rectangular section.
Barlow lens
A plano-convex lens between the objective and eye-piece of a telescope to increase the magnification by increasing the effective focal length.
Bar magnet
A straight bar-shaped permanent magnet, with a Pole at each end.
Bar mill
A rolling mill with grooved rolls, for producing round, square, or other forms of bar iron of small section.
Barn
Unit of effective cross-sectional area of nucleus equal to 10 -28 m². So called because it was pointed out that although one barn is a very small unit of area, to an elementary particle the size of an atom which could capture it is "as big as a barn door."
Also see
Barnacle
A small marine growth which attaches vessel's hull and will reduce its speed.
Barn door
Pair of adjustable flaps on a studio lamp for controlling the light.
Barney
A soft cover to reduce noise from a film camera.
BARO
  1. Acronym for Barometric Pressure
  2. Acronym for Barometric pressure sensor.
  3. Acronym for Barometric absolute pressure sensor
Barouche
Barouche

Barouche

A carriage where the driver sat in an open front seat while the passengers sat in two rows facing each other within the enclosed cabin much like a small stage coach. Only the rear passenger seat was protected by a folding cover.
Barograph
A recording Barometer, usually of the aneroid type, in which variations of atmospheric pressure cause movement of a pen which traces a line on a clockwork driven revolving drum.
Barometer
An instrument used for the measurement of atmospheric pressure. The Mercury barometer is preferable if the highest accuracy of readings is important, but where compactness has to be considered, the Aneroid barometer is often used.
Also see
Barometric absolute pressure sensor
(BARO or BP)
  1. A sensor that provides ambient atmospheric pressure information.
  2. Sends a variable voltage signal to the computer which varies in accord with atmospheric pressure, allowing adjustment of the spark advance, EGR flow, and air/fuel ratio as a function of altitude.
Also called a Barometric pressure sensor
Barometric and manifold absolute pressure sensor
(BMAP) A housing containing both BP and MAP sensors.
Barometric corrections
Necessary corrections to the readings of a mercury barometer for index error, temperature, latitude, and height.
Barometric error
The error in the time of swing of a pendulum due to change of air pressure. Though small, it is sometimes avoided in clocks by causing the pendulum to swing in an atmosphere of constant (low) pressure.
Barometric pressure
(BP) The pressure of the atmosphere as read by a barometer. Expressed in millibars (See Bar), the height of a column of mercury, or (SI) in hectopascals (SI units).
Barometric pressure sensor
(BARO or BP) A sensor found in the engine management system which detects the ambient barometric pressure so that precise fuel mixture can be maintained at different altitudes.
Barometric tendency
The rate of change of atmospheric pressure with time. The change of pressure during the previous three hours.
Barostat
A device which maintains constant atmospheric pressure in a closed volume, e.g., the input and output pressure of fuel metering device of a gas turbine to compensate for atmospheric pressure variation with altitude.
Barrage
Barrage balloon
A small captive kite balloon, the cable of which is intended to destroy low-flying aircraft.
Barred code
Any dialed code that automatic exchange apparatus is printed to reject by connecting the caller no further than number unobtainable tone.
Barrel
  1. A hollow, usually cylindrical, machine part, often revolving, sometimes with wall apertures
  2. The Air horn in the Carburetor. In particular, it is that part where the Throttle valve is located. If a Carburetor has four openings with a throttle valve in each, it is called a four-barrel carburetor.
  3. Another name for the Carburetor barrel, Cylinder, Cylinder barrel, Four barrel, Polishing barrel, and Single barrel.
  4. To travel fast as in We barreled down the highway well above the speed limit.
  5. The main cylinder in which molten polymer is prepared for extrusion or injection into molds.
  6. (bbl) A capacity of 42 US gallons (35 imperial gallons or 159.1 liters) frequently used as a unit in the oil industry.
  7. A round drum
Barrel cam
A cylindrical cam with circumferential or end track.
Barrel carburetor
Barrel distortion
Curvilinear distortion of an optical or electronic image in which horizontal and vertical straight lines appear barrel-shaped, bowed outwards. Also called positive distortion.
Barrel etcher
A device usually used to oxidize and thereby strip away hardened photoresist materials during semiconductor processing. In it a batch of wafers is exposed to a low-pressure oxygen plasma.
Barrel hopper
A machine for unscrambling, orienting and feeding small components during a manufacturing process, in which a revolving barrel tumbles the components on to a sloping, vibrating feeding blade.
Barrel Nut
An internally threaded screw with a slotted head.
Barrel plating
Electroplating of many small items by placing them in a perforated barrel revolving in a vat filled with an appropriate plating solution. The barrel is made the Cathode in the cell and the articles tumble against each other during rotation, continually touching at different places, and so become uniformly coated with the electrodeposit.
Barrel shape
A drum defect caused by excessive wear at the center of the friction surface.
Barrel tappet
A hollow rocker arm shaped like a barrel.
Barrel temperatures
Temperatures at which an extrusion or injection molding barrel is kept, usually rising to a peak at the nozzle. The range is determined by the polymer type and its melt viscosity.
Barrel Truck
barrel truck

Barrel truck

A hand cart (i.e., dolly) designed to move drums or barrels. Also called Barrel wheeler
Barrel-type crankcase
A gasoline-engine crankcase so constructed that the crankshaft must be removed from one end; in more normal construction the crankcase is split.
Also see
Barrel wear
A type of brake drum wear in which the center of the friction surface is worn more than the edges
Barrel Wheeler
Barretter
Iron-wire resistor mounted in a glass bulb containing hydrogen, and having a temperature variation so arranged that the change of resistance ensures that the current in the circuit in which it is connected remains substantially constant over a wide range of voltage. Also called ballast tube
Barricade
A temporary structure designed to warn vehicles that the road or a portion of the road is no longer usable.
Barrier
  1. In transformers, the solid insulating material which provides the main insulation, apart from the oil.
  2. The refractory material intended to localize or direct any arc which may arise on the operation of a circuit breaker.
Barrier cream
A special cream which is applied to your hands before working on a greasy engine. When the job is over, you can wash your hands and easily remove the grease stains. Also called invisible glove or silicon glove
Barrier effect
The effect produced by coating metal to shield it from corrosion.
Barrier layer
  1. In semiconductor junctions, the depletion layer
  2. In an optical fiber cable, an intermediate layer of glass between the low refractive index core and the high refractive index cladding.
  3. In general a layer placed so as to inhibit interdiffusion of heat, matter, etc.
Barrier paint
A primer which is used on bare metal to prevent corrosion.
Barring gear
An arrangement for moving heavy electrical plant, using manpower. Rotating machines and transformers are equipped with wheels and movement is possible by inserting crowbars at suitable points and levering the equipment.
Barring motor
A small motor which can be temporarily connected, by a gear or clutch, to a large machine to turn it slowly for adjustment or inspection.
Bar roof
Bars
Bar suspension
A method of mounting the motor on an electrically propelled vehicle. One side of the motor is supported on the driving axle and the other side by a spring-suspended bar lying transversely across the truck. Also called yoke suspension.
Bar-type current transformer
A Current transformer in which the primary consists of a single conductor that passes centrally through the iron core upon which the secondary is wound.
Bar winding
An armature winding for an electric machine whose conductors are formed of copper bars.
Bar-wound armature
An armature with large sectioned conductors which are insulated and fixed in position and connected, in contrast with former-wound conductors which are sufficiently thin to be inserted, after shaping in a suitable jig.
Barye
BAS
Acronym for Belt Alternator Starter -- a Hybrid vehicle system from GM
Base
  1. The lowest supporting part of an upright member.
  2. The bottom layer or coating in a series of paint coats.
  3. The major ingredient, other than pigments and filler, that make up the non-volatile portion of an adhesive, coating, or sealing compound.
  4. The region between the emitter and collector of a transistor, into which minority carriers are injected. It is essentially the control electrode of the transistor.
  5. The part of an electron tube which has pins, leads, or terminals through which connections are made to the internal electrodes.
  6. The thin flexible support on which a photographic emulsion or magnetic coating is carried.
  7. A layer of specified material of specified thickness placed below the road surface.
Base and clear system
Paint finish which is made up of a colored base coat (usually a metallic finish) and clear lacquer coat.
Base circle
As applied to the Camshaft the lowest spot on the cam, the area of the cam directly opposite the lobe or nose. No lift is produced by the base circle. Also called Cam heel
Base coat
The first coat in a paint system. It is either the undercoat or primer or a colored coat which is covered by clear lacquer.
Base gasket
The Gasket directly below the Cylinder and between the Cylinder and Crankcase. Also called cylinder gasket.
Base grease
Base idle
The idle speed determined by the throttle lever setting on the carburetor or throttle body while the idle speed control (ISC) motor, or any other computer-controlled idle speed control device, is fully retracted and disconnected.
Base interest rate
The interest paid on the usage of the vehicle during a lease. It is the cost of a lease before factoring in discounts, fees, and penalties and is not directly comparable to the APR for a loan. Lowering the base interest rate is one of the methods manufacturers use to subsidize leases. The phrase money factor measures the same cost and can be converted into a base interest rate. For example, to convert a money factor of 0.00276 into an approximate base interest rate would multiply the money factor by 24. The result would be 0.0662 or 6.6%.
Baseline
A fore-and-aft reference line at the upper surface of the flat plate keel at the centerline for flush shell plated vessels. Vertical dimensions are measured from a horizontal plane through the baseline, often called the molded baseline.
Base material
Any material (metal or plastic) which needs to be coated.
Base metal
  1. Metal that is under a coating or that needs to be coated.
  2. Metal to be welded, cut, or brazed.
Base model
The least expensive vehicle with the least amount of features as standard equipment. It has the smallest engine and often Manual transmission as well as few power equipment. Base models constitute only a small percentage of the cars sold. Sometimes called a stripper or stripped down unit.
Baseplate
A strong metal plate which is the main support for something.
Base rim
Base rim taper
Base Year
Basher
A small studio lamp placed close to or on the camera mounting.
Basic ignition setting
The ignition setting on a non-running engine according to the specifications. After the engine is running, the timing can be set more accurately.
Basic ignition timing
The ignition timing on a non-running engine according to the specifications. After the engine is running, the timing can be set more accurately.
Basic loading
The limiting mechanical load, per unit length, on an overhead line conductor.
Basic price
The price of a vehicle without including any optional accessories, taxes, delivery charges, etc.
Basic process
A steel-making process, either Bessemer, open-hearth, or electric, in which the furnace is lined with a basic refractory, a slag rich in lime being formed, enabling phosphorus to be removed.
Also see
Basic six
The group of instruments essential for the flight handling of an aircraft and consisting of the airspeed indicator, vertical speed indicator, altimeter, heading indicator, gyro horizon, and turn and bank indicator.
Basic slag
Furnace slag rich in phosphorus (as calcium phosphate) which, with silicate and lime, is produced in steel making, and ground and sold for agricultural fertilizer.
Basic speed
The speed which an electric motor develops at rated voltage with rated load applied
Basic steel
Steel which has reacted with a basic lining or additive to produce a phosphorus-rich slag and a low-phosphorus steel.
Basic T
A layout of flight instruments standardized for aircraft instrument panels in which four of the essential instrument panels in which four of the essential instruments are arranged in the form of a T. The pitch and roll attitude display is located at the junction of the T flanked by airspeed on the left and attitude on the right. The vertical bar portion of the T is taken up by directional information.
Basic timing
The ignition timing on a non-running engine according to the specifications. After the engine is running, the timing can be set more accurately.
Basic weight
The weight of the structure (wing, body, tail unit, and landing gear) of an aircraft, plus the propulsion system and the airframe services and equipment (mechanical systems, avionics, fuel tanks, and pipes). Includes residual oil and undrainable fuel but no operational equipment or payload.
Basin
Basing Point
A specified municipality or location within that municipality that a shipping company determines is on their route. The costs of shipping to that point is laid out in its rate book. However, if the delivery is to a nearby point, the rate is first calculated to the basing point and then a cost is added to the nearby point (if it is farther away) or subtracted (if it is before the basing point).
Basket case
An old car which probably does not run. Often many engine and transmission parts have been removed and are either missing or stored in the trunk or a basket
Basket coil
Coil with criss-cross layers, so designed to minimize self-capacitance.
Bass boost
Amplifier circuit adjustment which regulates the attenuation of the lowest frequencies in the audio scale, usually to offset the progressive loss toward low frequencies.
Bass compensation
Differential attenuation introduced into a sound-reproducing system when the loudness of the reproduction is reduced below normal, to compensate for the diminishing sensitivity of the ear toward the lowest frequencies reproduced.
Bass frequency
A frequency close to the lower limit in an audio-frequency signal or a channel for such, e.g., below 250 Hz.
Bastard
Something that is irregular, in between, or unusual.
Bastard file
Bastard File

Bastard File

A file (a tool) which has a coarse cut (as opposed to a finishing file). It is one cut finer than a coarse file. Files are classed as coarse, second cut, and smooth, from coarsest to finest. Thus, a bastard file is a cut in between a coarse and a second cut. The word bastard functions here in its meaning as irregular or neither coarse nor second cut.
Bastard thread
A screw-thread which does not conform to any recognized standard dimensions.
Bastard title
The fly page before the full title page of a book. Often wrongly called a half-title
Bat
  1. A lump or collection of something.
  2. Acronym for Battery
Also see
Batch
  1. A number of things which are produced as a group.
  2. A mixture of natural and synthetic rubber with other material such as fillers, chemicals, and vulcanizing agents in the production of tires.
  3. The mixture of raw materials from which glass is produced in the furnace. A proportion of cullet is either added to the mixture, or placed in the furnace previous to the charge. Also called charge.
Batch box
Batch furnace
A furnace in which the charge is placed and heated to the requisite temperature. The furnace may be maintained at the operating temperature, or heated and cooled with the charge. Distinguished from Continuous furnace
Batch mill
Cylindrical grinding mill into which a quantity of material for precise grinding treatment is charged and worked until finished.
Batch number
A number which may be added to a serial number to identify when the product was manufactured. In this way, when a problem occurs to some products of the same batch, action can be taken to correct or replace others from the same batch.
Batch Picking
A process in a warehouse or parts department where the picker selects several units of each product at one time to fill several orders and then distributes them to each order in a staging or packing location.
Batch process
Any process or manufacture in which operations are completely carried out on specific quantities or a limited number of articles, as contrasted to continuous or mass-production. In semiconductor manufacture, one in which several wafers are treated simultaneously as distinct from stages in which wafers are processed singly.
Bateau
French term for boat for a boattail shape of the rear of early race cars because it looked like the prow of a boat (upside down).
Bath
  1. A tub into which something is immersed.
  2. A liquid solution used for cleaning, plating, or maintaining a specified temperature.
Bath air
Bath air cleaner
Bath lubrication
A method of lubrication in which the part to be lubricated, such as a chain or gearwheel, dips into an oil-bath.
BA thread
Bath Suspension
Bathtub
Bodywork resembling an upside-down bathtub used on the rear of some Triumph motorcycles. It was introduced in 1957 and dropped in the early 1960s. It was also used on Nash cars of the 50's.
Bathtub combustion chamber
Bathtub chamber

Click image to supersize
Bathtub combustion chamber

The volume in the cylinder above the piston that is shaped like an inverted bathtub with the valves in the bottom of the tub. Since all the valves can be arranged in a single row, the valve-operating camshaft and/or rocker gear are simple to design and operate. The long, oval shape of the bathtub controls excessive turbulence, and the flat areas where the piston comes right up to the head surface supply the squish needed to swirl the mixture. The wide cylinders and short piston strokes in modern engines make it possible to use large valves with bathtub heads for efficient gas flow.
Battens
  1. Long strips of wood used in the mold loft for fairing lines
  2. Wooden protective strips in cargo holds
Batter level
A form of clinometer for finding the slope of cuttings and embankments
Battery
Battery

Click image to supersize
Battery

An Electrochemical device for producing electricity by converting chemical energy. The typical automotive lead-acid battery supplies the source of power for Cranking the engine and also provides the necessary electrical energy for the Ignition system. In addition, it can (for a limited time) furnish Current when the electrical demands of the vehicle exceed the Alternator or Generator output. Also called the storage battery.
Battery acid
Electrolyte (usually sulfuric acid) in each of the battery cells.
Battery acid tester
Battery Tester

Battery Tester

A hydrometer for checking the strength of the acid mixture in each cell of a battery. Fluid is sucked into the instrument by squeezing and releasing the bulb. The scale measures the acid.
Battery booster
A motor-generator set used for giving an extra voltage, to enable a battery to be charged from a circuit of a voltage equal to the normal voltage of the battery.
Battery brush
Battery Brush

Battery Brush

A specially designed brush set which cleans the outside terminals of the battery post as well as the inside of the battery cable so that good contact is made.
Battery cap
Small caps which seal each battery cell.
Battery capacity
The amp-hour capacity.
Battery cell
Individual compartments in a battery which is filled with electrolyte. Six-volt batteries have three cells, 12-volt batteries have six cells.
Battery case
The box made of polypropylene holding several chambers (cells) which have lead plates and filled with electrolyte.
Battery charge
The condition or state of the amount of electricity in a battery.
Battery charge indicator
An instrument which shows the state of charge in a battery.
Battery charger
Battery charger

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Battery Charger

An electric device which is plugged into an electrical outlet (e.g., 110 volt AC) and connected to the two terminals of the battery to restore the state of charge in the battery. One of leads coming from the charger is red and the other is black. The red lead is clamped on the positive post of the battery while the other is clamped on the frame of the vehicle.
Battery charging
The process of renewing the Battery by passing an electric Current through the battery in a reverse direction.
Battery charging station
With the advent of electric cars, there needs to be places where their batteries can be recharged periodically -- thus is born the battery charging station. Also called a charging point.
Battery clamp
A hold down device which secures the battery from moving around.
Battery coil ignition
High-tension supply for spark plugs in automobiles, in which the interruption of a primary current from a battery induces a high secondary emf in another winding on the same magnetic circuit, the high tension being distributed in synchronism with the contact-breaker in the primary circuit.
Battery compartment
A place in the vehicle where the battery is located. In cars and trucks it may be found under the hood (usually toward the front), under one of the seats, or in the trunk. In motorcycles it is found in the middle of the bike, under the seat.
Battery condition
Battery connector
A plug on battery-powered vehicles to connect the batteries to the Charging station
Battery Council International
A group which makes decisions related to battery composition and disposal.
Battery cover
The top of the Battery case. It has several holes (covered with caps) for access to the battery cells.
Battery cut-out
An automatic switch for disconnecting a battery during its charge, if the voltage of the charging circuit falls below that of the battery.
Battery discharge controller
A device on a vehicle which is driven by an electrical motor. It triggers a warning indicator when the battery power drops below a certain level.
Battery discharge indicator
An instrument on a vehicle which is driven by an electrical motor which indicates the percentage of the maximum charge of the battery.
Battery earth
British term for Battery strap or Ground strap
Battery filler
A device with a long hollow tube with a rubber bulb at one end. It is used for inserting into a container of Battery acid and sucking up the acid, then inserting into the battery cell to fill it. However, motorcycle batteries arrive from the manufacturer with no electrolyte (battery acid). Battery acid comes in a large plastic container with a rubber hose to which a metering clamp is attached. The container is usually placed on a higher shelf so that it is fed into the battery by gravity and regulated by the metering clamp.
Battery fill line
A horizontal line on the side of a translucent battery case which indicates the level to which you fill it with electrolyte. Usually there are two lines indicating a minimum level and maximum level.
Battery fluid
Battery hold down clamp
Battery ignition
Any system where the battery supplies the initial voltage to power the starter motor and fire the spark plugs.
Battery ignition system
Battery is dead
The battery does not have enough electrical power to start the car.
Battery is flat
The battery does not have enough electrical power to start the car.
Battery load tester
Battery Load Tester

Battery Load Tester

An instrument which is applied to the terminals of a Battery. When first installed, the battery voltage appears on the dial. By pressing a switch, the voltage is channeled through a series of resistors. While a battery may indicates 12 volts or more without a load, it may not meet the amperage for which it is rated when under load.
Battery Manufacturers
Battery master switch
A control which cuts power from the battery to the other components of the vehicle. Used to disable a vehicle so that thieves have a harder time stealing the vehicle.
Battery positive voltage
(B+) A term used to designate positive voltage at or near the battery level.
Battery post
The terminal on a battery to which the cable is attached. Older automobile batteries used a round post which stood up from the top of the battery. To avoid confusion, the positive post has a larger diameter than the negative. On newer batteries the post may or may not be abandoned in favor of a terminal on the side of the battery. On motorcycle batteries, the posts are usually flat with a hole for bolting the cables to them.
Battery regulating switch
A switch to regulate the number of cells connected in a series in a battery.
Battery spear
A special form of spike used to connect a voltmeter to the plates of the accumulator cells for battery-testing under load. The voltmeter incorporates a low resistance in shunt which simulates a heavy load on the battery, thus testing its work capability. The heavy current passed for this purpose necessitates special heavy duty battery connectors.
Battery state indicator
Battery strap
  1. A wire cable or braided wire strap to transfer electricity. It can be found between the engine block and the Chassis because the engine is isolated from the Chassis by rubber mounts. Also called ground strap.
  2. A rubber strap with metal hooks at each end and is used to secure a battery in place, especially on motorcycles.
Also see
Battery terminal
  1. A Battery post on the top of the battery or a lug with a hole on the side of the battery.
  2. The clamp at the end of a battery cable.
Battery tester
Battery Tester

Battery Tester

  1. A voltage meter or hydrometer for checking the state of charge of a battery.
  2. An instrument for checking the condition of the battery cells

Battery traction
An electric-traction system in which the current is obtained from batteries (accumulators) on the vehicles.
Battery tray
A metal or plastic on which the battery sits.
Battery vehicle
Baudelot cooler
Heat exchanger in which water flows by gravity over the outside of the tubes or plates.
Baudot code
Code in which five equal-length bits represent one character; sometimes used for teleprinters where one start and one stop element are added to each group of five bits.
Baulk
See
Baulk ring
British spelling for Balk ring
Bay
  1. Unit of racks designed to accommodate numbers of standard-sized panels, e.g., repeaters or logical units.
  2. An area in the warehouse designated by markings on the columns or floor.
  3. Unit of horizontally extended antenna, e.g., between masts.
Also see
Bayonet bulb
Bayonet cap
Bayonet Cap

Bayonet Cap

(BC) A cylindrical base of an electric bulb, usually with two pins projecting on either side, which engage in J-shaped slots to lock the bulb securely in its socket.
Bayonet fitting
An engineering fastening similar to a Bayonet cap
Also see
Bayonet holder
Bayonet socket
A socket for receiving a Bayonet cap. It has two slots on either side (usually J-shaped) to accommodate the bulb's pins.
Bay Storage
A designated area in warehouse or parts department used for storage.