507 Mechanical Movements - Brown Part 12 ppsx

exhausted out of suction-pipe, and waterdown-stroke, lowervalve is shutandvalvein pis-ton opens, and the water simply passes pis-ton is lifted up,and runs over out of spout at each up-st

exhausted out of suction-pipe, and water

down-stroke, lowervalve is shutandvalvein

pis-ton opens, and the water simply passes

pis-ton is lifted up,and runs over out of spout

at each up-stroke. This pump cannot

raisewateroverthirtyfeet high

449 Modern lifting pump. This pump

operates insame manner as one in

previ-ous figure, except that piston-rod passes

byaflap-valveopening upward Watercan

be liftedtoanyheightabovethispump.

valves The cylinder is above water,and

is fittedwithsolidpiston; onevalve closes

outlet-pipe, and other closes suction-pipe.

Whenpistonis risingsuction-valveisopen,

and water rushes into cylinder, outlet-valve

beingclosed Ondescent of piston

suction-valvecloses,andwaterisforced up through

outlet-valve toany distanceorelevation

additionofair-chambertotheoutlet, topn>

ducea constant flow Theoutletfrom

air-chamberisshownattwoplaces, fromeither

down-ward strokeot the piston,and expands and

presses out the water from the chamber

452 Double-actingpump.Cylinder closed

ateach end,and piston-rod passesthrough

stuffing-box on one end, and the cylinder

the pistonascending again,wateris forced

cylinder, and water enters lower

suction-valve,2.

one bellows is distended by leve>r, air is

rarefiedwithinit, and waterpasses^up suc-tion-pipe to nil space; at sametime other bellows iscompressed, and expels its

con-tents throughdischarge-pipe; valves

work-ing the sameasinthe ordinaryforcepump

454 Diaphragm forcing pump A

bel-lows,and valves are arranged same as in

preceding

455 Old rotarypump Lower aperture entrance forwater,and upperforexit.

Cen-tral part revolveswith itsvalves, which fit

accuratelytoinner surface of outercylinder.

The projectionshown inlowersideof cyl-inder is an abutment to close the valves

when they reachthat point

456 Gary's rotary pump Within the

fixed cylinder there is placed a revolving

fixed Revolution ofdrum causes

sliding-pistons,c, c, to move in and out in

obedi-ence toformofcam Waterenters andis

removed from the chamberthrough ports,

Land M; the directions are indicated by

arrows Camis so placedthat each piston

is, in succession, forced back to its seat when opposite E, and at same time other piston isforced fullyagainst inner side of

457

balance equalsaboutone-half ofweighttobe

j

raised, so that thebucket has to be pulled'

down whenempty, andisassisted inelevating

itwhenfullbycounterbalance.

raising water; the empty bucket is pulled

downto raisethefullone

459 Reciprocating lift for wells Topi

part represents horizontal wind-wheel ona

|

shaftwhichcarries spiral thread Couplingj

oflatter allows smallvibration, that it may

In center isvibratingtappet, againstwhich

meansofarminstepwhereinspiralandshaft

are supported, traversesspiralfromone wheel

to other so that the bucket which has

de-liveredwaterislowered andotheroneraised

460 Fairbairn's bailing-scoop, for

elevat-ing water short distances. The scoop is

ofliftmaybe altered byplacing endofrod

innotches shownin

figure.

461 Pendulums or swinging gutters for

raising water by their pendulous motions

disks, carriedbyendless chain,are adapted

towater-tight cylinder, and form with it a succession of buckets filled with water Powerisapplied atupperwheel

463 Self-actingweirand scouringsluice Twoleaves turn onpivots below centers;

in direction of stream, while lower turns againstit. Topedgeoflowerleafoverlaps

againstitbypressure ofwater In ordinary

states of stream, counteracting pressures

keep weirvertical and closed, as in the

left-handfigure, andwater flows throughnotcli

ordinarylevel,pressure above (rom greater

surface and leverage overcomes resistance below,upper leaf turns over, pushing back lower,reducing obstructionsand openingat

464.Hiero'sfountain Waterbeing poured

intolower; intermediate vessel being also

filled and more water poured into upper,

confinedair incavities over waterin lower

and intermediate vesselsand in communi-cation tubeonleft,being compressed,drives

byitselasticforce ajetupcentral tube

467 4-68

469

412

470

473

471

474

The amount offorce obtained is in proportion

totherelativeareas or squares of diameters of

the pump-plunger and ram. Suppose, for

in-stance,thepump-plungertobeoneinchdiameter

andthe ramthirty inches,the upward pressure

received by the ram would be 900 times the

467 Robertson's hydrostatic jack. In this

theramisstationaryuponahollowbaseandthe

cylinder withclawattachedslidesuponit. The

pump takes the waterfromthehollowbaseand

forces itthrougha pipeintheramintothe

cylin-der,andso raisesthe latter. At thebottomof

pipe thereisa valve operated byathumb-screw

to let back the water and lower the load as

gradually asmaybedesired.

468. Flexible water main, plan and section.

Twopipes of15and 18inchesinteriordiameter,

havingsomeoftheir jointsthus formed,conduct

water across theClydetoGlasgowWater-works

Pipes are secured to strong log frames,

hav-ing hhav-inges with horizontal pivots. Framesand

pipes were put together on south sideof the

river,and, the north endof pipe being plugged,

theywere hauled acrossby machinery onnorth

side, their flexible structure enabling them to

follow the bed

469. French invention for obtaining rotary

motion fromdifferenttemperaturesintwobodies

of water Twocisterns contain water: that in

left at natural temperature and that in right

higher Inright is a water-wheel gearedwith

of the latter a pipe extends overandpassesto

theundersideofwheel Machineis startedby

turningscrew in opposite direction to that for

raising water, thus forcing down air, which

ascendsin tube,crosses and descends, and

im-partsmotiontowheel; anditsvolumeincreasing

withchangeof temperature,it is said,keepsthe

471 Hotchkiss's atmospheric hammer;

de-rivestheforceofits blow from compressed

toacylinder, B,which is connected by a rod,

D, with a crank,A, on the rotary driving-shaft.

Asthe cylinder ascends, air enteringhole, e, is compressed belowpistonandliftshammer As cylinder descends, air enteringhole, e, is

com-pressedabove andis stored upto produce the

blow byitsinstantexpansionafterthecrankand

connecting-rod turnbottomcenter.

472. Grimshaw's compressed air hammer Theheadofthishammerisattachedtoapiston,

A, which works in acylinder,B,intowhichair

is admitted like steam to a steamengine above and belowthe piston by aslide-valveon top. Theair isreceivedfrom areservoir,C, in

the framing, suppliedby an airpump,D,driven

byacrank onthe rotarydriving-shaft, E

|tub invertedinlarger one. Thelatter contains

.waterto upper dotted line, and the pipe from

shaftor spacetobeexhausted passesthroughit

to a few inches above water, terminating with valve opening upward. Upper tub has short pipeand upwardly-opening valve at top,andis suspended by ropesfrom levers. When upper tub descends, great part ofairwithin isexpelled

through upper valve, so that, when afterward

raised, rarefaction within causes gas or air to ascend through the -lower valve. This pump was successfully used for drawing off carbonic acidfroma largeand deepshaft.

474 /EolipileorHero's steam

toy, described

by Hero,of Alexandria, 130 years B.C.,andnow

regardedas the first steam engine, the rotary

form*ofwhichitmaybe consideredtorepresent.

Fromthe lowervessel,or boiler, rise twopipes conducting steamto globular vessel above,and forming pivots on which the said vessel is

475

pipe entering at one side, with a nozzle directd toward the |

discharge- pipe. Ajet ofsteam entering throughAexpelsI

the air fromDandC, produces avacuumin B,andcauses ! 480. Anotherkind of gasometer. Thevessel, A, lias water to rise thftugh B,andpass through DandC,in a permanently secured within it a central tube, a, which slides regular and constant stream. Compressedairmaybe used

j

on a fixed tube, b, in the center of the tank,

as a substitute for steam.

476 Another apparatus operatingonthesameprinciple

as the foregoing It is termed a steam siphon Jjump

(Lansdell's patent). Ais the jet-pipe ; B, B, are two

suc-tion-pipes, having a forked connection with the

discharge-pipe, C. Thesteamjet-pipe entering at the fork offersno

obstacle to theupwardpassage of the water,whichmoves

upwardin an unbroken current.

477. Steamtrap forshuttingin steam, but providing for

the escape of water from steam coils and radiators(Hoard

&Wiggm'spatent) It consists of a box, connected atA

with the end o, the coil or the waste-pipe, having an outlet

at B,andfurnished with a hollow valve,D,the bottom of

which iscomposedof a flexible diaphragm Valve is filled

with liquid, and hermetically sealed,and its diaphragm

rests upon a bridge over the outlet-pipe. Thepresenceof

steam in the outer box so hsats the water in valve that the

diaphragmexpandsandraises valveupto the seat, a, a.

Waterof condensation accumulating reduces the

tempera-ture of valve ;andns the liquid in valve contracts,

dia-phragmallows valve to descendandlet water off.

478 Another steam trap(Ray's patent). Valve, a,

closesandopensbylongitudinalexpansionandcontraction

of waste-pipe, A, which terminates in the middle of an

at-tached hollow sphere, C. Aportionof the pipe isfirrnly

secured to a fixed support, B Valve consists of a plunger

which works in a stuffing-box in the sphere, opposite the

endof the pipe,andit is pressed toward theendof the

pipebya loaded elbow lever,D,as far as permitted by a

stop-screw, b, andstop,c. Whenpipe is filled with water,

its length is so reduced that valve remains open ; butwhen

filled with steam, it is expandedso that valve closes it

Screw, 6, serves to adjust the action of valve.

481. Wetgas meter. The stationary case, A, is filled with waterupto above the center. The inner revolving

drumis divided into four compartments, B, B, with inlets

around the central pipe, a, which introduces the gas through one of "the hollow journals of the drum This

pipe is turnedupto admit the gas above the water, as

indi-cated

bythearrow nearthe centerof thefigure. Asgas enters the compartments, B, B, one after another, it turns thedrumin the direction of the arrowshownnear its peri-phery, displacing the water from them. Asthechambers

pass over they fill with water again. The cubic contents

of thecompartmentsbeingknown, andthenumberof the revolutions of thedrumbeingregistered by dial -work, the quantity of gas passing through the meter is registered.

482. Gasregulator (Powers's patent)forequalizing the

supply of gas to all the burners of a building or apartment, notwithstanding variations in the pressure on the main, or

variations produced by turning gas on oroff,to or fromany

numberof the burners. Theregulator-valve,D,of which

a separateoutsideview is given, is arranged over

inlet-pipe, E,andconnectedbya lever, <i, with an inverted cup,

H,the lower edges of which, as well as those of valve, dip into channels containing quicksilver. Thereis r.o escape

of gas around the cup,H,but there are r.otches, /, in the

valve to permit the g.\s to pass over the surface of the

quicksilver. Asthe pressure of gas increases, it actsuyon

the inner surface of cup,H, which is larger than valve,

andthecupis thereby raised, causing a depression of the

valve into the quicksilver, and contracting the opening

notches, b, and diminishingthe quantity of gas passing through. Asthe pressure diminishes, an opposite result is

produced. Theoutlet to burners is at F.

483.Drygas meter Consists of two bellows-like

cham-bers, A, A', which are alternately filled with gas,and

dis-charged through a valve, B, something like the slide-valve

of a steam engine,worked bythe chambers, A, A'. The

1/.90

of waterintorotary motion.

485 Common wind-mill, illustrating the

production of circular motion bythedirect

action of the winduponthe obliquesails.

486 Plan of a vertical wind-mill The

sailsareso pivoted astopresenttheiredges

in returningtowardthe wind, buttopresent

their faces to the action of the wind, the

directionof which is supposed tobeas

in-dicatedbythearrow

487 Commonpaddle-wheelforpropelling

vessels; therevolution of thewheelcauses

the buckets topress backward against the

water and so produce the forward

move-mentof the vessel

488 Screw propeller. The blades are

sections of a screw-thread, and their

revo-lution in thewater has the same effect as

propelling thevessel

489 Vertical bucket paddle-wheel. The

buckets,a, a,are pivotedintothe arms,fr, fr,

at equal distances from theshaft Tothe

pivots are attached cranks, c, c, which are

pivoted at theirendstothearmsof aring,

ec-centric,e. Therevolution of thearmsand

also to rotate upon the eccentric, and the

view Ontheshaftof thehand-wheelthere

is abarrelon which is wounda ropewhich

passesround the guide-pulleys and has its opposite ends attached to the "tiller"

or

leveron the top of therudder; by turning the wheel,oneendof the rope iswoundon andthe otherletoff,andthe tiller is moved

in one or the other direction, according to

the direction inwhich thewheel isturned

491 Capstan Thecable or ropewound

onthebarrel of the capstanis hauled inby

turning the capstanonits axisbymeansof hand-spikes or bars inserted into holes in the head The capstan is

prevented from turning back by a pawl attached to its lower partandworkinginacircularratchet

onthe base

Lev-el's). The upright standard is secured to the boat, and the tongue hinged toits up-per end enters an eye in the level which

standard Asimilarapparatus isappliedat each end of the boat The hooks of the

tackles hook into the tongues, which are secureuntilit isdesiredtodetach theboat,

whena rope attached-to the lower end of

eachleveris pulledinsuchadirectionas to

slip the eye at the upper end of the lever

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