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No. 13 June 1959

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AI]TOilIATICAI,IBARIIITIIOTOR51(27.90RA SC PC AM Bulletin 24p)

T his caliberoutterlSrmod,ernn d,esign nd,measuringbut 4.5 millimeters..in height, will proae especiallysuitablefor extremely thin watches. Thanks to itstapering outline, t has beenpossibleo deuiseattrac-tiae cases f suprerneelegance.Exceptionally long running is secured,hrough theautomatic winding of the mainspring, actuatedby arotor operating n both lirections.

CHARACTERISTICSTotal diameter 28.40 mmCasing blank diameter 2?.90 mmHeight of rotor 4.5 mmTapping diameter of winding stem 0.90 mm19,800 per hourft comprises:I bridge for barrel and center wheelI bridge for third wheelo fourth wheel and escape wheelI pallet bridgeI cock (balance bridge)2 bridges for automatic device constituting a block inilepenilent

of thc moaement

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24 jer.r'els, ncluding 19 olive-hole jewels for gear-train, escape-mento also for upper and lower bridges of automatic device2 cap-jewels for balance2 pallet-stones and the roller jewelI beryllium-bronze [ushing at upper pivoting point of arborin banel bridge

Rosy gilt with large waves? diamond polished bevels

The mainspringo to which is soldered a brake springo is madeof stainless alloy; it is unbreakable and does not warp. Thanketo ite 7 turns of development, it will secure a duration ofrunning over 50 hours from the moment when the watch is(f"lly) wound up.

The third wheel, while revolving over the center wheel, is madeto meeh with the seconds pinion on the one side and with thecenter pinion on the other side; so there is no driving wheelover third wheel.

The escape wheel and pallet are made of steel whereas theroller is in rosy gilt brass.

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Balanee.hairspring

' l lhe rtort-rnagrret ic assetrt lt l l colrr l lr istrsl ra lancc the ar lv : rn lages o1 'u l t ich havr ,

tu 'o ln l )ensat i r r i l la t ha i rspr i r rg ar r t l a l r t , r r l i r r r r r - l rn rnze t ' rc r r lessl reer r l t , sc r i l re< ln t l r r ' ' l 'e r : l r r r ica lGui tk r No. I2 .

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This organ, which we happen to use for the first time inone of ou r calibersoallows of quickly and most accuratelysetting the balance to oobeat-point". This horologicalterm means that the balance and hairspring being at astandstillo the roller jewel should be exactly positionedon a straight line from the center of pallet to the centerof balance, which considerably facilitates adjusting in thevarious timing positions.Said movable stud holder, made of brass and freelyfitted into the cockoreceiveso n central hole thereof, theIncabloc shock resistant device, the fitting of which isalso free. The Incabloc bolt, operating just like a frictionspring, secures, on the one side, the Incabloc device onthe face of cock and, on the o ther side, the movable studholder against the lower portion of said face.

Regulator pointer Incabloc,Stud holder

IIncabloc bolt

When adjusting the watcho first set the balance to oobeat-point" then only afterwards, move the regulator. Bymeans of the vibrograph and without interfering in anyway with the balance, the "setting of beat-pointoo isperformed by rotating the stud holder in either directionuntil the two straight dotted lines on the paper chart aremade to touch or superpose each other. (See figureopposite.)

., Regulator

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Uneoslng thetnoocment

' l ' l re set t ing scre l has l r t .e r r upt ' rseder l r r un a- r lc cas t in tegra lrvith thc sett ing lever itsclf ; a sprirrg blat le narnetl pressrrleslrr ing lirr sett ing lever'. l ieeps it r lol 'rr on th e lr latc. The dispo-s i t ion fh t ' i l i t a tes r rncas i r rg he rnovement : as a nra t t c l o f fa t ' t .A lnere l ) ressure r rnder thc set t ing lever ax l t ' , l r1 - r r rc : r r rso1 'apo in ter l t .oo l " ' i l l re lease he l ' in t l ing s tern .

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\#{a Autotnatla rrrlndlngdeolee' l 'he sc l f r ' in t l ing rner :han is rns hor rser lrv i th in a l r lo r : k in r lepent lcn t o I ' thel'atclr rn()\ 'ernent antl f i t tet l thereotrlr1' I lo scro\f 's. Thanks to this ar-ranFernent, it is possible to turn olrt .s i rnr r l l . aneor rs lv he rnove l t t c l r t ant lthe rr ' int l ing mecltatr isrn. l"t trt l tcr-rnor t ' , i t i s tnos t l r rop i t io r rs l i r r kec l r -ing a l l par ts a l rsohr te lv c lean t l r r t tug l r -or r t thc rnar r r r fac ture o l ' l . l r t r u 'a tc l trnovcnrent . So the s 'a tchrnaker u i l lf nrl u'ithin eits\- rt ,at: lt the variortsorgitns o{'rvlr it ,}r he u'i l l [n1,g 11; [1s1rlithe r r rnn ing.As thc ar r to tnat i t : l r lock is i t r t c r -r,hartgcablc, the n'al. t 'h-rcIairer t,aneas i lv rep lac t r i t . in t :ase o l ' need" l rvanothcr l r lo r , k taken l rorn a s tockthat u- i l l l r c cons t i t r r ted in the rna-terial r lepartrnent o1' all orrr Agents.'I ' lre rotor is matlc to srl ng eithcrclockl' ise ol r:ounterclockl- ise throu ghth e slightest gestures of the l-r ist:in both cases it secures ample u'ind-ine of the watch.

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MANUAI,V/INDINGWhen winding the watch by means of the manual windingmechanism, the latter actuates a f irst ratchet No. 550.1100called main ratchet wheel which is freely fitted on the innerdrop of a second ratcbet, squareholed, No. 550.1465 calledautomatic ratchet wheel f ixed on the barrel arbor bv rneansof sc rew No. 2718.The autornatic ratchet wheel is driven by the main ratchetwheel through a satell i te pinion No. 550.1441, in mesh rviththe inner teeth of the automatic ratchet rrheel.

Ratchet wheelsassembled on barrel-arbor

On winding, the main ratchet wheel revolves in the directionshown by arrow F I ; i t drives the satell i te pinion which, beingin contact rvith the inner teeth of the automatic ratchet r.heel,starts revolving in the direct ion shown by arrow F2. At once,leaf A is made to lean against tooth C, which causes th e satell i tepinion to be blocked up and, through leaf B thereof, then incontact with tooth D, to drive the automatic ratchet wheel inthe direct ion of arrow F3, thus operating th e 'rvinding of main-spring.When the automatic device is functioning, the automaticratchet wheel revolves in the direct ion shown by arrow F4,its inner teeth then drive the satellite pinion in the directionof arrolr. F5 and makes it turn freely; from that moment, th esatellite pinion having no longer any action upon the mainratchet wheel, the latter remains at a standstill.

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AUTOMATICWINDINGTH E AUTOMATIC S/ INDING DEVICE inc ludes

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V/ INDING CEAR Dcompriseshe followingparts:W'inding pinion G, 'rrhereonis driven a threarlednu t l, ith square,th e superior u'in

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REYOLYES CLOCKWISE (see igure1).The rotor pinion A while mov-ing in the direction ofarrow F1drives the large wheel of wind-ing wheel B whicho in its turn,causes the superior windingwheel DS to revolve in thedirection shown by arrow F2;through pinion G, the superiorwinding wheel DS actuates thedriving wheel for ratchet wheelE, and the pinion thereof rvillcommunicate its motion toautomatic ratchet wheel F inthe direction of arrow F3o thuswinding the mainspring.

Figure IFUNCTIONALDESCRIPTIONOF THE MECHANISMWHEN THE ROTORREVOLYESCOUNTER-CLOCKWISEseeigure2).When the rotor pinion A movesin the direction of arrow F4 itsuccessively drives the wheels ofwinding wheel B and C. Thesmall wheel Co meshing withinferior winding wheel D I,makes the latter revolve in thedirection of arrow F2. Throughits pinion Go said inferior wind-ing wheel actuates the drivingwheel for ratchet wheel E" andthe pinion thereof will commu-nicate its motion to automaticratchet wheel F in the dilectionof arrow F3o thus winding thewatch.

FUNCTIONALDESCRIPTIONOF THE MECHANISMWHEN THE ROTOR -^

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HO\ff THE SUPERIORAND INFERIOR WINDING S/HEELS OPERATEON WINDING (seeigures , 3 and 4).When the rotor turns clockwise the large wheel for windingwheel B cauees he superior winding wheel DS to revolve in thedirection of arrow F2; the tooth O of its inner teeth N, whencoming into contact with leaf R of superior satellite pinion K,drives the latter in the direction shown by arrow F5. Thereuponoleaf S of satellite piniono made to lean against tooth P of thewinding wheel, blocks up the pinion which, through its pivotodrives the winding wheel core J in the direction shown byarrow F6.The winding pinion G fitted through its sguare on the windingwheel core, then transmits the motion to the driving gear forratchet wheel E.When the rotor turns counter-clockwise, the small wheel forwinding wheel C drives the inferior winding wheel Df ; theseorgans perform their duty in the same manner as for the supe-rior winding wheel DSo but through the inferior satellite pinion(see figures 2 and 4).Let us mention that when one of the winding wheels is operat-ing, the other winding wheel turns idle, but in the oppositedirection.

Figure 3

On manual winding, the driving wheel for ratchet wheel Eactuates the pinion of winding wheel Go fitted to the windingwheel core Jo n the direction of arrow F7; the satellite pinion Kdriven by the inner teeth N of winding wheel then revolvesfreely in the direction of arrow FB (see figure 5).

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Figure 5

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550.1026

550.1464

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fnserted between a lower bridgeand an upper bridgeo the me-chanism of the automatic blockis composed of the followingparts:

The gib ofrotor 550.1451, ixedby its screw 2631 to upperbridge 551.I03I, securing th erotor on axle thereof.

The 2 Bcrews 2044 used forfixing tle automatic block onto the plate.The rotor axle 550.1400 fittedto the upper bridge by 3 screws263t.Driving gear for iatchet wheel550.1437.

Winding gear 550.1464.Large wheel of winding wheel550.r453.Small wheel of winding wheel550.r454.Bearing for driving gear forratchet wheel 550.1438ixed tolower bridge by its screw2138.Both ecrews 3401 and 3402that fix lower bridge 550.1033to upper briilge 551.103I.

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550.1454

551.1033

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Jewel for drivingof ratchet wheel

Rotor axle

Teeth of the large wheelof winding wheel

Teeth of the small wheelof winding wheel

Pivoting center for drivinggear ofratchet wheel

Jewel for large

Dip the gib of rotorin a piece of elder-pithmoistened with oil

Jewel for winding wheel

Jewel for large wheelof winding wheel

Jewel for small wheelof winding wheel

Jewel for winding wheel

Jewel for small wheelof winding wheelof winding wheel

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Iq Hole of the inferiorwinding wheel

Hole of pivoting centerof inferior satellitepinion

Hole of pivoting centerof superior satellitepinion

Hole of the superiorwinding wheel

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Hole of pivoting centerof satellite pinionof ratchet wheel

Pivoting place of handratchet wheel to theautomatic ratchet wheel

Seat of hand ratchetwheel to the automaticratchet wheel

Inner teeth of automaticratchet wheel

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To disassembleand reassemblesaid gear it is necessaryto utilize the fitting and the nut wrench devised forthat purpose.

When disassembling, proceed as follows:Place the gear through the 2 notches of piniono uponthe fittingo then screw off the nut counter-clockwise bymeans of the nut-wrench.To reassemble he gear, first place the pinion upon thefitting, then locate successively the other parts on thepinion, while carefully oiling, as indicated hereon, andscrew the nut with the wrench.We keep these tool-sets at your disposal.

Nut wrench- ---\\- r

fnferior nut

Inferiorwinding wheel

fnferiorsatellite pinion

Winding wheelcore

Suporiorsatellite pinion

Superiorwinding wheel

Fitting

Windingpin ion\

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The styling oJ the OMECA moilels which Jor manyyears will haae to suit the euerfi,ner taste oJ he publicis a matter oJ constantly reneweilworlr.

The originality anil irnagination oJ he d,esigners aueoJ necessity o adapt themselues o the size and shapeoJ the calibero and, this goes aery oJten against therequirements oJ beauty or elegance.Thanks to its special prof,le and to its reduceilheight,caliber 551(27.90RA SC PCAM Bulletin 24 ewels)can befitted into thinner cases.

The new "Constellation" CK 14381shousn ere is aperJect example thereoJ. To its many well knownqualities has beenaild,eil hat oJ a stream,linedappear-ance which will be appreciated euerywhere.

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