To stop car {brake, vehicle}|, an asbestos pad rubs against a metal disk {disc brake} or cylinder {drum brake}. Brake pedal pushes piston into cylinder {master cylinder}, forcing oil {brake fluid} into tubes to wheels. Tube ends at wheels have a small piston in a cylinder. Piston connects to a brake part {brake shoe} that holds the pad. Pressure forces shoe against brake drum or disc.
Surface-mining excavators {dragline}| remove soil and rock over mineral deposits {overburden}, using buckets on booms.
Drills {drill press}| can use pressure and tip cutters, to make holes.
tools, equipment, fasteners, and materials {hardware}.
soil pulverizer and/or smoother {harrow}|.
ridge grid {hatching}|.
Cones {megaphone} can direct and amplify voice.
Space vehicles that return to Earth have a front heat shield {nose cone}|.
A heavy weight can drop {pile driver}|, to force a rod into ground.
Metal spikes {piton}| can have an eye to attach rope.
A weight {plumb bob} can hang by string from a point, to measure vertical.
iron or rope ring {quoit}.
Parachutes have a rope {ripcord}|, pulled to open parachute.
Devices {servomechanism}| can be part of feedback loops, so machines automatically adjust or turn on or off.
Protective coverings {sheathing, cover}| can be around or over objects or buildings.
cloth rows {shirring}.
Vehicles have pistons in tubes that push oil through small openings to dampen motion {shock absorber}|.
Machines {stenotype}| can have special keyboards for stenographers, such as court reporters or closed captioners, to type shorthand.
Devices can have subdevices {subassembly}|.
Bridges {suspension bridge}| can use two tall towers as posts. Giant cables, woven with many steel wires, go from one side, over first post, down to middle, up over second post, and down to other side. Straight cables hang from the giant cables to hold roadway.
Boards can have groove on one board edge and ridge on other edge {tongue and groove}| {dressed and matched}, so tongue and groove mesh, as in hardwood floors.
Roadway pressure-sensitive stripes {treadle}| count number of vehicle axles and speed and direction.
Ultrasound waves cause fluid compaction and rarefaction {cavitation, cleaning}, which cleans objects by pressure {ultrasonic cleaner}|.
Scales can have a small movable scale {vernier}| that slides along main scale and indicates fractions.
small mechanical device or controller {gadget} {widget}.
Presses {winepress}| can crush grapes under cool pressure, to obtain juice.
grinding {milling}.
joining pipes {pipefitting}|.
hammering {forging}|.
Falling drop forge half-die hits hot metal in stationary anvil half-die {drop forging}|, to make crankshafts, axles, and other large items.
Upright cylinders {churn}| can hold cream, and turning or raising and lowering a paddle makes butter or buttermilk.
A rough metal wheel scrapes against flint {cigarette lighter}|. The spark created lights lighter fluid or compressed butane. A glass fiber wick sucks lighter fluid. Compressed butane expands and vaporizes through tiny hole.
Draw curtains {curtain}| can use one string loop {drapery pull}. String lies in traverse rods. Loop attaches to right-hand curtain at top left and attaches to left-hand curtain at top right. Loop goes around pulley at curtain ends. Curtain hangs from holders in sliding rod. First holder pushes other holders back when curtain opens and spreads other holders out when curtain closes.
A forked stick {divining rod} can be for locating underground water sources.
Rulers {ferule} can strike children.
rocking horse {hobbyhorse}.
Braided necklaces {lanyard} can be for hanging a key or whistle.
Instruments {metronome}| can sound a frequency.
Babies can suck small rubber bulbs {pacifier}.
Razors {razor}| {straight razor} can have a blade with concave sides {hollow ground edge}. Leather straps {strop} can smooth edges. Razors {safety razor} can have plastic bars, which rest on face to prevent blade from gouging skin.
protective goggles {safety glasses}|.
Shoe-shaped inserts {shoetree} can stretch shoes.
Feathers {shoofly} can blow away flies.
A logarithmic scale on a moving piece can move past a logarithmic scale on a stationary piece {slide rule}|, to add exponents to perform multiplications or multiply exponents to raise numbers to power.
Metal cones {snuffer}| on rods can extinguish candles.
walking pole {staff, pole}.
Bottles {Thermos bottle}| can have two glass layers, with vacuum between. Glass layers have silvered surfaces facing each other, to reflect heat. Glass bottle attaches to container with rubber supports. Foam rubber, or plastic with many small compartments, is in ice buckets, refrigerators, and freezers.
Cylindrical cones {thimble}| can have textured tops and push needles through cloth.
Conveyor belts {treadmill}| can roll as people walk.
Metal forks {tuning fork}, with two long tines, can resonate at one frequency.
Devices {typewriter}| can print letters.
roller
A roller {platen} can rotate to move paper forward and back. Roller can slide back and forth, to allow typing anywhere on line.
process
When a key depresses, a lever moves type bar onto paper on platen. Shift key raises or lowers type bar to allow uppercase or lowercase letters to strike. Levers have angles so keys hit at same position. Depressing a key can rotate a wheel of raised letters into position for a hammer to strike from behind. Depressing a key can rotate a ball of raised letters into position for pressing against platen.
slide
When type bar, wheel, or ball returns to normal position, it hits a release lever that springs platen one space to right.
A movable plate can squeeze against a stationary plate {vise}|, to hold object.
Ridged boards {washboard}, can rub clothes when washing.
Slide fasteners {zipper}| [1890 to 1913] can have sliders that guide hooks into each other, at bottom. Slider top goes over zipper ribs, on hook outer edges, to line up hooks on inside.
Velcro uses two tapes {Velcro zipper}|. One tape has many small plastic hooks. The other tape has loops.
Anthracite coal subjected to high electric current makes soft carbon graphite. Graphite mixed with water and clay goes through holes in a steel plate. An oven dries and bakes the graphite rods. Machines apply wood covers {pencil, writing}|.
To sharpen pencils {pencil sharpener}|, hold pencil by hand or pincers in a tube. Handle goes to wheel with gear teeth inside and with tube to hold pencil. Two rollers are on opposite tube sides, in a V shape, with point at handle end. Rollers have gears that engage wheel. As handle turns, rollers and tube rotate. Helical edges on rollers peel off a thin wood layer.
Flat surfaces at angles to horizontal {inclined plane}| can allow lifting loads over longer distances, instead of straight up, requiring less force. Inclined-plane angle is in degrees or is ratio of height above horizontal to distance along horizontal.
Inclined planes can wind around axes {screw}|. Most screws are right-handed and screw in clockwise.
Helices {corkscrew}| can screw into corks. A lever pushes down on bottle top to pull out cork.
Bars {lever}| can apply force to a point at one end, using movement over long distance at other end. Bar rotates around bar point {fulcrum} near force end, where it contacts a fixed object. Crowbars are levers.
Long rods or structures {boom, crane}| can hold loads.
Bridges can use two large triangular, or diamond-shaped, steel frameworks {cantilever}|. Cantilevers balance on posts. Frameworks meet at bridge center.
Bars {crowbar}| {wrecking bar} can have wedges at one end and hooks with a claw foot at other end.
Balances {scale, weighing} {balance, scale}| can have V-shaped or horizontal beams, with pivot points at center and two pans at ends {weighing, scale}. Scales {pendulum scale} can pull against a pair of weighted pendulums. Balances {pan balance} can have pans. Balances {steelyard} can have one pan and a movable weight {poise, balance}, which can slide along a horizontal arm. Balances {platform weigher} can allow object to be anywhere on platform, because platform parallel linkage always keeps platform horizontal. Platforms can be on springs or have a steelyard.
Simple locks {lock} {lock and key}|, for chests or cases, have a keyhole and a key that looks like a little flag {key, lock}. When flag turns 360 degrees in lock, flag pushes a pin that slides a bolt in or out.
Door locks can use a key with blade ridges and slots on blade sides. Lock has a barrel. In lock barrel and wall are five small rods {pin} on springs in vertical tubes. Pins have two pieces, at different heights corresponding to ridges on key blade. When key is in lock, dividing lines for pins are at same radius as barrel radius, so barrel can turn. Barrel turn moves a bolt.
Locks {combination lock}| can have three discs. First disc connects to a knob and has a protrusion. The protrusion hits a protrusion on second disc, which has a protrusion that hits third-disc protrusion. Turning knob, to turn first disc two complete clockwise turns, engages the three discs. At first number, knob stops and turns counter-clockwise. Only first disc moves. After complete turn, second disc engages again. At second number, knob stops and turns clockwise. Only first disc moves. At third number, first disc stops and disc notches align. Bolt can slide past disc edges.
ankle cuff or chain {fetter}.
handcuff {manacle}.
Door locks {night latch}| can have an inside knob and an outside keyhole.
drill or sail structure and machinery {rig, structure}|.
holder {gig, holder}|.
A rod or shaft {bearing, machine}| can turn in a sleeve full of oil. Lubricated-for-life bearings use a porous bronze sleeve soaked with oil and sealed to keep out dirt and prevent oil evaporation.
Two metal rollers {calender}| can squeeze together plies or texture coverings.
Pear-shaped rollers {cam}|, pushing on rods, can raise and lower rods.
A toothed wheel goes under can rim {can opener}|. Knife-edge or wheel cuts just next to top rim. Two arms squeeze knife-edge toward toothed wheel.
Cylindrical holders {carousel}| can rotate horizontally.
Tools can have a handle {crank, machine}| at one end and holder at other, to allow turning wheel.
Reels {fishing reel}| can have a spool for line, with a handle to turn spool and a guide to lay line down evenly on spool. A knob can let spool spin freely without turning handle or can brake and lock spool. Fishing reels {spinning reel} can have a fixed spool with axis pointing along rod toward fish. A guide {bail, fishing reel} on cup surrounding spool goes around spool, laying down line. Enclosed spools can have a hole in front.
Wheels can have an inner ridge {flange}|, to prevent wheel from falling off track.
Fasteners {hinge}| can rotate around an axis or pin {hinge pin}. Hinge sides {leaf, hinge} can attach on door or jamb outside surface {surface hinge} or on door or jamb edge {mortise hinge}. Hinge pin can insert into holes {knuckle, hinge}. Leaf with more knuckles is on hinge stationary part. Hinges {loose hinge} can allow one leaf to slide off pin of other leaf. Hinges {piano hinge} can have a permanent pin with two leaves that can meet parallel and flat.
To cut grass {lawn mower}|, hand lawn mowers {reel-type mower} have metal bar {cutting bar} at grass level and four helical reel blades, which scissor grass on cutting bar as reel turns with rolling wheels. Motorized mowers {rotary blade lawn mower} have two-blade propeller at ground level, which spins rapidly, sucks grass straight up, chops grass, and blows grass out. Slip clutch allows motor to keep spinning if blade becomes stuck. Motorized mowers start by pulling cord to spin motor crankshaft.
Wheels {ratchet wheel}| can have angled teeth, typically with pawl engaged in tooth, pressed down by spring. Oscillations in both directions turn into intermittent angular motion in one direction. If spring and pawl have higher temperature than rotor, ratchet tends to go backwards. Perhaps, muscle contraction involves linear ratchet effect.
Tools {sector tool}| can have two arms, with pivot at end, and be for numerical calculations, in same way as nomogram.
Rods {spit}| can hold an animal over coals to cook, and a handle can turn the rod.
Balances {torsion balance}| can use rods that twist.
Vanes {weather vane}| can point in direction from which wind comes, because force is greater on back-end larger surface.
Centrifugal pendulums {whirling regulator}| can control rotation speed in windmills.
Lathes can scrape wood {woodturning}|.
A ring holding a lower object, for example a ship's compass, can be in a base with two axes {gimbal}|, so ring stays horizontal when base tilts.
Spinning discs or circles {gyroscope}| {gyroscopic compass} can be in bearings {gimbal bearing} with three axes, which allow motion in any direction. Gyroscopes maintain space orientation. Laser beams can split and go through two paths, with different lengths if platform rotates, measured by wave interference. Paths are at triangle corners. Mechanical gyroscope rotation causes precession, which makes magnetic field. Semiconductor gyroscope vibrates in electric field against springs, and rotation changes vibration.
A rod has a spherical head and a joined rod has a hollow spherical receptor {ball and socket joint}|.
Two rods can hinge at obtuse angle {toggle joint}|, and rods have hinges at other end. Force at central hinge pushes far ends outward.
Two shafts can link at two axes {universal joint}|, perpendicular to each other and to shafts. Universal joint allows free movement in all directions.
Mechanical joints {caster, furniture}| {furniture caster} can allow swivel and roll.
structure
A shaft rotates around vertical axis. Shaft holds an axle around which wheel or sphere rotates. Wheel can swivel and roll freely, so furniture can move easily.
types
Bent tubes can hold both vertical shaft and wheel shaft {skew caster}. Balls can be set in vertical holders {ball caster}.
speed
Casters typically wobble at higher speeds.
brakes
Casters can have brakes. Pedals prevent roll but not swivel.
Objects {swivel}| can have a central sheath holding a post attached to a base, allowing horizontal object rotation.
Wheels {pulley}| on axes can have rope with which to lift loads by pulling down.
Two pulley sets {block and tackle}| can pass rope back and forth over wheels {block} {tackle, pulley}. Rope pulled long distance supplies force to raise load short distance.
Pulley middle wheels {idler wheel}| allow drive wheel and driven wheel to turn in same direction.
Tire tops can tilt {camber}| out or in, rather than be vertical.
amount
Camber ranges from -1.0 to +1 degrees. Negative camber tilts in. Positive camber tilts out. Positive camber allows better support by wheel bearings.
turn
Tires tend to tilt out toward outside turn, because tread sticks to road and tire top has centrifugal force.
When car body slides toward outside turn, MacPherson strut suspensions tilt tires out, but unequal A-arms tilt tires in. During turns, tire inside or outside can lift off road. Negative camber for MacPherson strut suspensions and positive camber for unequal A-arms allow tires to be vertical during turns, when traction is most important.
pull
If one tire has higher camber, car pulls to that side.
road
Because road crown pulls car to right, in right-hand-drive countries, left tire can require higher camber.
Tires can lean to front or rear {caster, tire}, rather than be vertical. Positive caster is forward tilt. Too much positive caster causes shimmy, because weight falls in front of tread. Too little positive caster causes poor tracking, because weight falls down tire center.
Caster settings typically are 0.5 to 4 degrees. From 3 to 4 results in better straight-line tracking but heavier steering. From 0.5 to 1 makes lighter steering, but poorer straight-line tracking.
Negative caster is backward tilt. Negative caster puts weight behind tire and causes unstable tracking, because it pushes tire forward in various directions.
Tires can swivel left or right, rather than aligning straight-ahead {toe}|. Toe is in or out. It causes stability because, during turns or bumps, tires tend to return to straight-ahead position. At higher speeds, toe becomes slightly more out, so starting slightly in is better. Out is only for front tire center offset or special wheel bearings. Rear tires are neither in nor out, because in or out causes instability and rapid tire wear.
A raised post {pommel, saddle}, in saddle front, can hold hand or rope.
pommel {saddlebow}.
strainer or sieve {colander}|.
Food forced through colander with small holes {ricer}| makes texture like cooked rice.
Steel-wire pieces in U shape {staple, stapler} are lightly glued together to make a row of staples. Spring presses row of staples against front of device {stapler}|. Front has a slot the width and breadth of one staple. Metal press has width and breadth of one staple. Pushing down metal press pushes one staple down front slot. At bottom, concave grooves {anvil, stapler} curve staple points in or out. Industrial staplers cut and shape steel wire, just before stapling.
Thin magazines staple {magazine stapling}| in center of fold {saddle stitch}. Thick magazines staple from edge front to back {side stitch}, with a glued-on cover.
In frames {weaving}|, threads are strung lengthwise evenly from top to bottom {warp, weaving}. Frame width is cloth width. Other threads pass over and under warp threads {weft, weaving}, from bottom up. Frame presses weft thread down next to one below.
Continuous frames {loom}| can weave cloth.
parts
Looms have rollers {loom beam}, on which warp threads are wound tight. Warp-thread even-numbered ends pass through loops in middle of vertical wires on a frame {heald}. Odd-numbered warp threads pass through loops on second heald. Warp threads pass through frame vertical wires {reed, frame} and attach to second roller. As one heald rises, the other falls, so shuttle carrying weft thread can pass through. Reed presses new weft thread against previous weft thread.
types
Weaves {plain weave} can go over and under alternating warp threads, so weft threads go over and under same warp threads. Weaves {canvas weave} can go over and under every two warp threads, so weft threads go over and under same warp threads. Weaves {twill weave} can go over and under every two warp threads, so alternating weft threads go over and under different warp threads.
In weaving, a holder {shuttle}| slides back and forth to place woof thread above and below warp threads.
Piles of short, thin fibers {spinning fiber}| can make thread. First, people attach several fibers to wood or metal bar {spindle}. Fiber pile is next to spindle. As spindle turns, it pulls out more fibers from pile and winds fibers tight. After that, twisting several threads together makes larger and stronger string or twine.
Machines {spinning frame}| can draw and twist fibers into yarn and then wind yarn.
Spinning frames {spinning jenny}| can have several spindles.
Wheels {spinning wheel}| can turn a spindle, to twist fibers into yarn.
lengthwise threads {warp, thread}.
Threads {weft, thread} can be across warp or fabric texture.
Store windowpanes tilt outward at top and inward at bottom to minimize reflections {store window} {window display}. Reflections go down into sidewalk.
Windows {casement}| {window} can have glass doors hinged on side, top, or bottom. Latches lock windows shut. Cranks can open windows.
Windows {louvered window}| can have horizontal glass slats. Cranks with a worm gear tilt glass slabs shut or open.
Bay windows {oriel}| can project out from wall.
Wood or metal slats {venetian blind}|, suspended from strings, can cover windows. Cord raises bottom slat and so pulls up other slats. Locking lever at top right-hand side holds raising cord, to keep blinds up. Left-side cord pulls strings up on one side and down on other side, to change slat angle.
Windows can have separate top half and bottom half {window sash}| {sash, window half}. Bottom has cords at two top corners. Cords go through window top-part edge, over pulley in window-frame side, down to weights {sash weight}. Small screwed-on doors are on lower frame sides, allowing access to weights. Sash windows {double hung sash} can move top and bottom panels.
Crossbar and neck holders {yoke}| can be for two draft animals.
U-shaped ox collars {oxbow} allow ox to pull something.
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Description of Outline of Knowledge Database
Date Modified: 2022.0225