DICTIONARY OF AUTOMOTIVE TERMS - "Ba"
- β:
-
- Symbol for phase constant.
- Symbol for ratio of speed to speed of light.
- The intermediate refractive index in a biaxial crystal.
- b:
-
- Symbol for susceptance in an ac
circuit (unit is the siemens; measured by the negative of the reactive
component of the admittance)
- 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.
- [B]:
- A Fraunhofer line in the red of the solar
spectrum, due to absorption by the Earth's atmosphere. [B] Is actually a close
group of lines having a head at a wavelength 686.7457 nm.
- 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's metal
- Babbitt metal:
- See:
babbitt
Babbitt's 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%.
-
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:
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:
- Acronym for " Blood Alcohol Content"
- Back:
- A large vat used in various industries, such as dyeing, soap-making, and brewing.
Also spelled "beck"
Also See:
blow back
die-back
die back
kamm back
popping back
spine-back
- 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:
annealing
temper
- Back axle:
- The rear axle.
- Back axle ratio:
- See:
final drive 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 frame
- Backbone chassis:
- See:
backbone frame
-
Backbone frame:
A 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.
Also See:
tubular backbone frame
- 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:
feedback
regeneration
- Back diode:
- See:
backward 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.
- Backfire:
-
- Passage of unburned fuel mixture into the
exhaust system where it is ignited and
causes an explosion (backfire) prematurely.
- 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.
- 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:
- See:
loop scavenging
- Backflushing:
- See:
flushing the 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.
Also See:
signal-to-noise ratio
- Background job:
- A task having a low priority within a multiprogramming system.
Also See:
foreground/background processing
job queue
time sharing
- 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.
Also See:
microwave background
- Background video:
- (BGV) A technique for overlaying video on previously recorded depth multiplex
audio. Also called video on sound (VOS).
Also See:
depth muliplex recording
- Backhand welding:
- Welding in the direction opposite to the direction that the gas flame is
pointing. Also called backward welding.
Also See:
forehand welding
- 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:
-
- Some material placed on the root side of a weld to aid control of
penetration.
- Light-absorbent layer on the rear surface of photographic film or
plate to reduce halation
- A meterological term describing the changing of a wind in a
counter-clockwise direction.
Also See:
veering
- The book binding process by which one half of the sections at the back
of a volume are bent over to the right and the other half to the left. The
projections formed are joints, to which the case is
hinged, by hand or machine. Some machines also simultaneously perform
rounding
Also See:
steel backing
- 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:
- The part of a drum brake to which the wheel cylinder(s) and the
brake shoes are attached.
- A pressed steel plate upon which the brake shoes, wheel cylinder,
and anchor pin are mounted.
Also See:
brake backing plate
- Backing-up:
-
- Printing on the second side of a sheet.
- 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:
-
- 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.
- Mechanical deficiency in a tuning control, with a difference in dial
reading between clockwise and counterclockwise rotation.
- Property of most regenerative and oscillator circuits, by which
oscillation is maintained with a smaller positive feedback than is required for
inception.
- Backlight:
-
- The rear window of a vehicle. Most people call it a "rear window" and
erroneously think of "backlight" as the taillight.
- 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 liquid crystals.
-
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 lining:
- See:
hollows
- 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:
- A sort period of black level signal transmitted
at the end of the horizontal sync pulse before the
picture information.
- 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:
-
- 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.
- Pressure in low side of refrigerating systems; also called suction
pressure or low-side pressure.
- The pressure opposing the motion of the piston of an engine on its
exhaust stroke.
- The exhaust pressure of a turbine. Increased by clogged or defective
exhaust system.
Also See:
exhaust back pressure
negative back pressure valve
negative back pressure
modulated valve
-
Back pressure modulated:
- See:
negative back pressure
modulated valve
-
Back pressure modulated valve:
- See:
negative back pressure
modulated 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:
- See:
negative 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:
-
- Projection of a picture, from film, transparency, or video, on to a
translucent screen to be viewed from the opposite side,
- 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. Compare
forward scatter
- Back-seat:
- 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).
- Back seating:
- Fluid opening/closing such as a gauge opening; to seat the joint where the valve
stem goes through the valve body.
- Back sight:
- See:
back observation
- 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.
Also See:
pie-roll
- Back-step:
- See:
black-step marks
- 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. Frequently used with
thyratrons and ignitrons
- 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.
Also See:
self-induction back-voltage
- 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 explicit congestion notification:
- A method of dealing with overloading in a frame
relay or asynchronous transfer
mode network by setting a specific bit in the header of a
frame or cell sent back from
the destination to the source of traffic. On receiving this frame, the source
reduces its offered load.
- 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:
- See:
backward shift
- 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 signalling:
- Signalling from the called to the calling end of a circuit.
- Backward wave:
- In a travelling-wave tube, a wave with group velocity in the opposite direction
to the electron stream. Compare forward wave
-
Backward-wave tube:
- General term for a family of microwave
travelling-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:
- See:
backhand 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.
- Back wave:
- See:
spacing wave
- BAC level:
- Blood Alcohol level.
- Badge:
- An emblem with a manufacturer's name and/or logo on a plate to identify a model
or component.
Also See:
bonnet badge
hood badge
- 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 tendency of a manufacturer to engage in
badge engineering
-
Baffle:
- 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.
- Extended surface surrounding a diaphragm of a sound source
(loudspeaker) so that an acoustic short-circuit is prevented.
- Any device to impede or divide a fluid flow in a tank to reduce
sloshing of liquid.
- Plates fitted between cylinders of air-cooled engines to assist
cooling.
- Internal structure or electrode, with no external connection, used in
gas-filled tubes to control the discharge or its decay.
Also See:
arc baffle
box baffle
- 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:
-
- A metal plate that acts as a baffle.
- 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.
- Plate inserted into waveguide to produce change in mode of
transmission.
- Bag:
- See:
air bag
courier bag
cruiser bag
driver air bag
passenger-side air bag
shot bag
side impact air bag
tank bag
- 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).
- Bagnet:
- See:
bar bagnet
- 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. Used also 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 and
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:
- See:
bear 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:
core sand
- 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.
- 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:
-
- The state in which weight is evenly distributed.
- The action of applying weights or drilling holes in something to
establish even weight distribution so that vibration is reduced.
- Adjustment of sources of sound in studios so that the final
transmission adheres to an artistic standard.
- 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.
aerodynamic balance
balance shaft
brake balance
counter balance
crankshaft counter-balance
current balance
dynamic balance
harmonic balancer
heat balance
kinetic balance
off-car balance
on-car balance
spool balance valve
static balance
steering wheel balance
tire balance
wheel balancer
- 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-bridge:
- See:
bascule bridge
- 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. A
push-pull amplifier is an example.
-
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.
Also See:
unbalanced circuit
-
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 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.
Compare co-axial cable
- 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.
Also See:
swell pedal
-
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:
- See:
balanced line
-
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:
- See:
dummy piston
- Balance point:
- Any point where a mass-haul curve cuts the
datum line, showing that up to the point all excavated material has been used up
in embankment.
- 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.
Also See:
ac balancer.
harmonic balancer
wheel balancer
-
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 tab:
- A tab whose movement depends upon that of the main
control surface. It helps to balance the aerodynamic loads and reduces the
stick forces. Compare
servo tab, spring
tab, trimming tab
- Balance valve:
- See:
spool balance valve
- Balance weight:
-
- A lead weight attached to the rim of a wheel.
- 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.
- 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:
wheel weight
- Balancing:
-
- 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:
balanced engine
- Keeping wheels in balance.
- 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.
- The process of adjusting a traverse, i.e., applying corrections to
the different survey lines and bearings so as to eliminate the closing error.
Also See:
wheel balancing
neutralization
off-the-car balancing
on-the-car balancing
- 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 capacitance:
- See:
neutralizing capacitance
- 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:
wheel balancing machine
- Balancing speed:
- See:
free-running speed
- Balancing weight:
- See:
wheel 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:
- See:
crawling
- Balk ring:
A friction-regulated pawl or plunger used to make the
engagement of gears easier. British spelling is "baulk ring"
- Ball:
- A sphere usually made of metal when used in automotive applications.
Also see
ball and spring
ball bearing
ball joint
ball joint rocker arm
check ball
detent ball and spring
hitch ball
impact swivel ball universal joint
recirculating ball and nut steering
recirculating ball steering
recirculating ball worm and nut
recirculating ball
towing ball
- Ball and nut:
- See:
recirculating ball and nut
steering
-
Ball-and-nut steering:
- See:
recirculating ball steering
- Ball and socket:
- See:
ball joint
-
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 joint
- Ball and spring:
Also See:
detent ball and spring
- Ballast:
-
- Any liquid or solid weight (gravel or stone) placed in a ship to
change the trim, increase the draft, or to regulate the stability.
- 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.
- Sandy gravel used as a coarse aggregate in making concrete.
Also See:
dry ballast
lead ballast
liquid ballast
-
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 signalling 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)
-
- 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.
- 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:
barretter
- Ballast tank:
- Tanks at the bottom or sides of a ship which are filled with seawater for
ballasting purpose.
- Ballast tube:
- See:
ballast resistor
- Ball bearing:
- An antifriction bearing consisting of an inner and outer
hardened steel race (or
cage) separated by a series of hardened steel balls.
Also See:
annular ball bearing
linear ball bearing
recirculating-ball thread
- 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:
-
- A process that occurs in the cementite constituent of steels on
prolonged annealing at 650° -700°C.
- 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 missile:
- See:
missile
-
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:
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 haave a grease nipple to
allow periodic lubrication.
- 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:
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.
Also See:
barrage balloon
- 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.
Also See:
length fold collection
- 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 1925-1948 model automobiles 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. Compare
hollow glass microspheres
- 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:
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:
-
- The inner or outer steel ring forming one of the ball tracks of a ball
bearing.
- 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:
- See:
recirculating ball steering
- Ball track:
- See:
ball bearing
- Ball universal:
- See:
impact swivel ball universal joint
-
Ball universal joint:
- See:
impact swivel 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:
- See:
recirculating ball worm and nut
- Ball worm and nut:
- See:
recirculating 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 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.
Also See:
absorption band
allowed band
back band
brake band
frequency band
power band
squish band
- 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:
brake band
- 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.
Also See:
band theory of solids
- 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.
Also See:
optoelectronics
- 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:
-
- 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.
- Defect in videotape recording heads causing visible horizontal bands
in the picture.
- 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:
- See:
citizens band radio
-
Band-rejection filter:
- See:
band-stop filter
- Bands:
- See:
band
- 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:
-
- 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.
- 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.
Also See:
energy band
conduction band
valence band
- Bandwidth:
-
- The range of audio frequencies that an audio component (radio) can
handle.
- 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.
- 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.
- The range of frequencies within which the characteristics of a device
(filter, amplifier, etc.) are within specified limits, often the points at
which the performance has changed by 3 dB from a mean level, or the
half-power points.
- B & S:
- See:
bore and stroke.
- 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:
-
- A colloquial term used to express the
cylinders in an engine. Often used with a number
such as " six banger."
Also See:
four banger
- A British colloquial term for beater
(an older, cheaper, well-worn car which is still usable).
- One who fakes an accident.
Also See:
car banger
- 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:
- See:
car banging
- Banjo:
-
- 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.
- A drum-shaped central part of an axle casing containing the
differential.
Also See:
rear axle housing, banjo type
axle housing banjo
- 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.
- 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:
cylinder bank
- 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.
Also See:
dead bank
- Banked fire:
- See:
banked boiler
- Banking:
-
- The slope of a track from the wall to the
apron, generally measured in the corners.
- 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.
- 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:
-
- A raised footway inside a bridge parapet.
- A ledge on the face of a cutting.
Also See:
berm
- Bar:
-
- A unit of pressure. One bar equals 100 kilopascals
(10 5Pa) or 750.07 mm of mercury at 0°C and
latitude 45° or about 14.5 psi.
- A rod.
- 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
- Material of uniform cross-section, which may be cast, rolled, or
extruded.
Also see:
angle bar
anti-roll bar
antiroll bar
anti-sway bar
antisag bar
arbitration bar
armature bars
balance bar
boring bar
bulb bar
bull bar
bumper bar
bus-bar
compensating bar
compensator
extension bar
freeway bar
gunwale bar
header bar
hi-way bar
highway bar
hood bar
ladder bars
landau bar
landau bars
levering bar
locking bar clamp
main bar
nerf bar
nudge bar
port bar
push bar
roo bar
side impact bar
sissy bar
spring bar
stabilizer bar
stringer bar
strut bar
sway bar
t-bar
targa bar
test bar
tommy bar
torsion bar
track bar
traction bar
tread bar
wear bars
wheelie bar
wheelie bars
wobble extension bar
- 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 as in "I saw a driver take his trailer to the
barbershop last week."
-
Bar clamp:
A tool with a stationary head and a sliding foot for clamping purposes.
Also See:
locking bar clamp
- Bare:
- A term signifying slightly smaller than the specified dimension. Compare
full
- 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:
Short handlebar extensions which are attached to the ends of a mountain bike
handlebar.
-
Bar end shifter:
A bicycle gear shifter that is inserted into each of the ends of a handlebar.
- 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:
tank-barge
- Barge carriers:
- Ships designed to carry barges.
- Bar generator:
- Source of pulse signals, giving a bar pattern for testing TV cathode-ray tubes.
- Barium ferrite:
- See:
ferrite
- Bar keel:
- See:
keelson
- 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 bagnet:
- 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:
cross-section
- Barn door:
- Pair of adjustable flaps on a studio lamp for controlling the light.
- Barnett effect:
- Magnetization of a ferromagnetic material by rapid rotation of the specimen.
Used to measure magnetic susceptibility.
Also See:
Einstein-de Haas effect #E#H
- Barney:
- A soft cover to reduce noise from a film camera.
- BARO:
-
- Acronym for barometric
pressure sensor.
- Acronym for
barometric absolute pressure
sensor
- 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:
altimeter
-
Barometric absolute pressure sensor: (BARO or BP)
-
- A sensor that provides ambient atmospheric pressure information.
- 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:
- 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.
-
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:
- See:
balloon barrage
- Barrage balloon:
- A small captive kite balloon, the cable of which is intended to destroy
low-flying aircraft.
- Barred code:
- Any dialled code that automatic exchange apparatus is printed to reject by
connecting the caller no further than number unobtainable tone.
- Barrel:
-
- A hollow, usually cylindrical, machine part, often revolving,
sometimes with wall apertures
- 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."
Also See:
carburetor barrel
four barrel carburetor
four barrel
- Another name for the carburetor
barrel, cylinder,
cylinder barrel,
four barrel,
polishing barrel, and
single barrel.
- To travel fast as in We barrelled down the highway well above the
speed limit.
- The main cylinder in which molten polymer is prepared for extrusion
or injection into molds.
Also See:
injection molding
- (bbl) A capacity of 42 US gallons (35 imperial gallons or 159.1
liters) frequently used as a unit in the oil industry.
- Barrel cam:
- A cylindrical cam with circumferential or end track.
- Barrel carburetor:
- See:
four barrel carburetor
single barrel carburetor
twin 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.
Also see:
pincushion 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.
Also see:
semiconductor device processing
- 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 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.
Also see:
injection molding
-
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:
split crankcase
- Barrel wear:
- A type of brake drum wear in which the center of the friction surface is
worn more than the edges
- Barrel winding:
- See:
drum winding
- 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:
- See:
A-frame barricade
breakaway barricade
- Barrier:
-
- In transformers, the solid insulating material which provides the
main insulation, apart from the oil.
- The refractory material intended to localize or direct any arc which
may arise on the operation of a circuit breaker.
Also see:
crash barrier
- 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:
-
- In semiconductor junctions, the
depletion layer
- In an optical fiber cable, an intermediate layer of glass between the
low refractive index core and the high refractive index cladding.
- In general a layer placed so as to inhibit interdiffusion of heat,
matter, etc.
-
Barrier-layer capacitance:
- See:
depletion layer capacitance
- Barrier paint:
- A primer which is used on bare metal to prevent corrosion.
-
Barrier penetration:
- The passage of a sound wave, at an angle for which
Snell's law predicts zero transmission, through a
very thin layer.
- 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:
- See:
T bar roof
- Bars:
- See:
armature bars
bar
ladder bars
landau bars
wear bars
wheelie 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.
Also see:
torsion bar 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:
- See:
microbar
- Base:
-
- The lowest supporting part of an upright member.
- The bottom layer or coating in a series of paint coats.
- The major ingredient, other than pigments and filler, that make up
the non-volatile portion of an adhesive, coating, or sealing compound.
- 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.
- The part of an electron tube which has pins, leads, or terminals
through which connections are made to the internal electrodes.
- The thin flexible support on which a photographic emulsion or
magnetic coating is carried.
Also See:
bead base
edison base
flat base rim taper
flat base rim
lithium base grease
load base
negative load base
rim well base
- 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:
- See:
lithium 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:
- Metal that is under a coating or that needs to be coated.
- 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.
Also see:
distributor baseplate
- Base rim:
- See:
flat base rim
flat base rim taper
- Base rim taper:
- See:
flat base rim taper
- 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