US2196998A - Method of making watch dials - Google Patents

Description

April 16, 1940. A LQDGE 2,196,998

` METHOD 0F MAKING WATCH DIALS v Original Filed May l5, 1935 ,7 V Li. 72.

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l PatenredfApr. 16, '1940 UNITED sTATleis l i 19am llPATENT OFFICE c METHOD oF MAKING WATCH nIALs l Alvin Lodge, Lancaster, Pa.,- assignor to Hamilton Watch Company, Lancaster, Pa., a corporation 4of vPennsylvania original application May 15, 1935,v serial No. 21,622.4 Divided and this application August 4,

` 1936, `Serial No. 94,295

12 Claims.

within the area from which said projections eX- tend.

Heretofore projections or pin-like membersr havebeen extruded from the stock ofl metal v blanks or strips such as bythe method disclosed in the patent to Jeremiah McGrevey, No. 1,632,305, granted June 14,- 1927, and assigned to the assignee of thepresent application,` where is taught a process for putting so-called feet on watch dial numerals which are receivable in openings of very small diameter, disposed around the marginal or'peripheral edge of the Watch dial face. These projections of Watch dials numerals are of less diameter than the thickness of the material from Which they are extrudedl and, therefore, no blemishes appear on the outerface of the article formed and'in the case of watch numerals Whatever blemish, if any, that exists is so infinitesimal that it `is not apparent to the naked eye. y

An entirely different condition exists, however, when it is desired to extrude integral projections from ablank or strip of largerarea, or Where 'it is desirable and necessary to extrude projections from a portion of a blank or a strip which'projections are to have al diameter, in the finished product, not less than the thickness of the area of the blank or strip from which they are extruded, because this results, .among other disadvantages, in a blemished ,opposite surface of the blankorstrip. y

The ypresent method,therefore, is essentially that of subjecting the metal blank or strip to.

herein shown and described particularly with respect to themanufacture of Watch it is particularly applicable.' Y

Watch dials are attached to a pillar plate by several spaced apart `feet insertedin' holes for dials to which (Cl. 29-177) f the respective feet lin they pillar plate and therein secured. It hasalways been in the practice, until the production of my invention about to be set forth, to provide separate feet or pins andattach them to the metal backing plate of the dial,

provided in that metal plate for the purpose. In itself, although lso long persisted in, the procedure just described is subject to certain disadvantages: (l) the inability to obtain accurate alignment of Ithe feet, (2) `When the feet are apusually by soldering-the feet at one end in holes plied to dials which are to be covered With a] n thin layerof enamel or other plating, the solder becomes dislodged `and thel feet become loose or lost; (3) When'th'e dial is covered or plated With arsuitable dial facing material, the heat of the solder frequently mars the dial `-face; (4) in curved dials the recesses or holes, providedvfor cedure.. This is notably true in these-called Wrist or strapk Watches so universally Worn;

The principal object of myv invention has been the solution Aof the problems, thus created, ina j Way that Will be wholly .satisfactory'from` the j standpoints `of manufacture and the watch prod-` uct itself. A particular object of my inventionis to solve such problems in connection With the strap or wrist Watch, especially with such a Watch having a concave curvature on the side thereof next to the Wrist of the wearer. In solving the problems, I have provided a methodfby. which a metal plate or strip is formed with integral projections thereon of a diameter or thickness not less than the thickness of the area.` of the plate from which they extend, sothat the platefand projection are an integral unit, the projections being composed of metal extruded'from the plate and being of accurate dimensions and acouy rately positioned irrespective ofthe contour or shape of the plate in. its final nished form for use, While at the same time the opposite' surface ofthe plate. is smooth, homogenous and unblemished at theareasthereof from Which the' projections are extruded.

'I'he watch dial shown and described herein is not claimed in this application as it forms the `subject matter of my application Serial No.

by or isincluded within the terms or scope o f l the appended claims. Y Inasmuch. as my invention has Ibeen developed, as v1E have explained, in connection with the curved type of wrist or strap watch, it will facili.- s

tate illustration and description of my invention in its broad aspect as welles that particular application of it, toshow in the drawingQillustrations of a watch dial of that description and the method or procedure in producing sucha dial. v In the accompanying drawing:

Figs. l to 'l are, respectively, illustrations in plan view of the changing form from blank t completed dial; and Figs. la to 5c are, respectively edge views thereof; f v l Fig. 8 is an edge view ofthe dial the pillar plate shown in section; y

Fig. 8c isan end View of suchdial; Figs. 9 to 1l are, respectively, views of upper and lower dies employed in producing the changes in the blank as shown in Figs. 2 to 5, portions of the lower die being in staggered section approximately along the l2 and 6 oclock axis as shown by section line 9 3, Fig. 3 and through the holes into which the feet are extruded. The dies for performing the operations illustrated in Figs. 2 and 3 are substantially those shown in Fig. 9 and the blanks shown in Figs. 2, 2c, 3, 3a, l and 4a,

applied to are illustrated in the drawing in a position of' about 9U degrees from that which they assume in the dies of Figs. 9 andv l0, as shown in thev dialfor a curved wrist watch, a brief preliminaryl description appears desirable. The dial A., shown in Figs. 7, 8 and 8a of the drawing, is of an 0blong form with the greater dimension or length y in the line of the opposite dial numerals 5, i2',

and thecurvature being in that direction. Several of these dial positions or numerals are indicated onv the blanks in Figs. 2, 3, 4, and 5 for the'sake of clarity. The dial show is solid sterling silver or plated with silver, and the numerals are engraved or impressed in the outer surface of the plate. The curvature of the outer surface is convexly cylindrically curved from end to end, and the under surface,.or they one next to the pillar plate, is concavely dished in the same direction, the plate being thinned down towards each end with the central or intermediate portion substantially thickened and thevcentral or intermediate portion is attened so that it will lie flat against the adjacent at upper surface of the pillar plate (see Figs. 5a, 6a and 8). The integral feet are situated respectively n-ear the ends,y or 6 and l2 oclock edges, and are located of necessity at or near the thinned edges of the plate for obtaining the greatest possible accuracy in the pisitioning of the dial. Thelocation ofthe projections or feet of watch dials must be suchas to insure accuracy in disposition on the watch movement, which in vturn insures accuracy of time, and to avoid interference with other parts of the watch. Thus in thercurved dial, shown lin the drawing,"the lprojections or feet are located at portions of the dial which,fdue toits shaping, are too thin for the attachment oi separate feet orpins by soldering their ends in' recesses drilled into onev face of the dial.

The curvature of a dial vfor watches as well as other small instruments, is desirable for the sake of appearance and alscvfor the practical reason of. providing clearance for adjacent parts of the instrument.

Heretofore therewere two methods commonly employed to provide Such dials. One method was to'bendv or curve'or shape the dial by the hands. or bytools vordies'so that the opposite sides or Ysurfaceswere curved, the thickness of the dial'throughout remained approximately the same. 'Ihe other method involved the addition orremoval of material from eitherv the-face or tol the back of the dial' to produce the necessary" shape. By both of these procedures thethickness of the dial varies and feet may be appliedv thereto, but if applied after forming, the feet I must be attachedtc sloping surfaces which cause the feet to extend at improper angles for reception in the openings provided therefor in the pillar plate of the watch; or, if the usual recessl for attaching the feet is drilled in the thin dial to facilita-tev attachment of the feet to' align with the pillar plate openings, the recess will be at such an angle with respect to the sloping surfaces of the dial `that a portion of it will come through the Qpposite side of the plate, thus marH ring itand rendering attachment diiiicult.

In positioning the dial on ,the pillarplate, it is.

essential to the accuracy of the timekeeping properties of the watch that the feet shall be parallel and solocated as to rit nicely in the openings of the pillar plate so that set screws may be screwed into the feet' or some other means provided for securing the dial Yto the pillar plate. Accordingly accuracy of alignment and' positionf ing ofthe feet on the dial platev are essential.

This accuracy is attainable by my method which forms the dial and the feet thereon simultane-- ously, or as parts of one continuous operation,

with the feet orprojections inv proper position thereon, but is not possible by such methodsy as I have described involving bending or lmachining or by separatefeet or pins soldered or l'other-k blocks, each die 'being mounted on a Suitable n holder not necessary to sho-wv ordescribe.

The blank l0, in Fig. .1, is "first subjected to operation of the dies l2 and I6 in Fig.v9, where it willbe seen that the lower die I2; has a iiatcr 'plane upper face and" extending downward therefrom is a central hole I3 and ltwo feet form-y ing holes I4, shown apart infthe particular.

case illustratedp-for the flow ofmetal from the blank for the formation ofthe feet, while the lower-and cooperating face l5 of the upper die Hi, is cylindrically conveXly curved. The action of Lthese dies on the blank gives the blank the form shown in Figs. 2 and 2a.

The first operation reduces'th-e thickness of the blank/through the center forcing the metal out to the sides of'theblank, thus leaving the side marginal portions --thicker than the center portion. As 'the metal is flowed or shifted from the center toward the sides,` the flow forces the metal down into the openings I4 for providing the rudimentary projections 26 from which the feet 3I) (Figs.'8 and 8a) are eventually formed.

Fig. 9, excep-tthat the cooperating surface of H the upper dies has a curvature on. a greater I cavelyl curved .depression 24.

radius in order to further force the metal towardy the sides of the blank to additionally thin vit in the center and to add metal to'the rudimentary projections 26, the openings I 4 being enlarged for this purpose.

`In Figure 10, lower die II, for producing the development of the blank, shown in Figs; 4 and 4a, has its upper operating face witha. concavely cylindrical depression I8, at the central portionthereof, the theoretical axis of the curvature being in the direction substantially at right angles to the axis of the curvature of the dies shown in Fig.\9, (and, in respect to the dial shown, in th-e direction of the 3 to 9'oclock edges of the dial). Such curvature I8 may, but not necessarily,.terminate at each side in line with one of the foot-forming holes I4 and, from that point outward to the periphery of the die I'I, the surface 22 inclines downward at a slight angle while the working face of the upper die has a cylindrically convex face I9 (similar to die I6, Fig. 9), extending to the periphery of the face.

The depression I8 is for the purpose of causing e metal to flow toward the center of the blank from portions lying opposite the humps or raised causes the metal to shifter flow and replacesA certain of' the metal squeezed in thev preceding operations from the center of the blank to the side thereof. l

-To producev the development shown in Fig. 5, the dies in Fig. 11 are employed which may be such as are suitable for the shaping desired. For the dial herein disclosed, the lower die 20 has a central ilatvsurface 2I,-A instead of the concave surface shown in Fig. '10, and the angle of the adjacent downwardly inclined surfaces 22a is somewhat greater than vthe surface 22 in Fig. 10; and the upper die 23, shown in'Figs. 11 and 14, has on its lower working face a cylindrically ccn- The "width of the depression 24,- extending from left to right in Fig. 11, corresponds to the length of the nished dial (from-12 to 6 oclock members) ywhile the axis of `the depression, extending from left to right inFig. 14 I(taken at right angles to the View in Fig. l1), runs along the 3 to 9 numerals on the dial.

It will be observed thatthe holes I4 into which the metal flows, or is extruded during' .the swaging operations, have each at the entrance an enlargement with conveXly rounded surfaces 25 which produces the llet 26a at the junction of the foot 25 with the dial plate and that the radius of curvature of thatconvexy surface is gradually diminished in the successive operation produced by the vlower dies I2, ITI and 20, and

y effect from the provison of the. hole takes place.

the die holes I# provided also for allowing the e, necessary inthe subsequent steps.

`squeezed to the center. In Figs. 4 and 5, the cen' that diminution of radius is carried to the next die (not shown in vthel drawing) for producing the track and which backs up the dial when the next to the last operation is performed of impressing the track and numerals of the n- 5. ished dial in the dial face. Inthe track impressing operation the `diminution of radius causes additional pressure' to be applied above the feet-forming holes to compensate for any possible inaccuracy in the dies.

At the same time the track and numerals are impressed 'upon the faceof the dial, a circular depression 'Ila may beimpressed into the un-` derneath side o-f the dial for a purpose to be next described. The result of the dial impressing o-p- 1I! eration is the development shown in Figs. 6 and 6a, and in that stage, it is of 'circular or disc form with the perfectly formed and parallel integral feet 30, and with a circularcentral depression I Ia concentric with the central hole II, and with the thickened central portion c having `tapering margins at the 6 and v12. oclock edges e so thatthe final product is that shown in Fig. 391 I 7,-a dial of oblong form with the' longer side edges slightly curved outward.

The central hole II, may or may not be ypro-- e vided in the blank Ill'. The purpose kof the hole is two foldit may be used to center the blank, and also to reduce'the pressure b-y permitting inward flow of the metal toward the center of the blank as pointed out below. Means other than a hole may be provided for centering the blank. When so provided itl enables flow ofthe metal towards the center, where it ismost desirable to remove metal and thereby reduces the pressure which tends to distort the dies that are used further along in theV process after that The rst die operation substantially closes the hole II and actually forms a burr or cylindrical projection 4U on the upper side of the dial blank the center of the blank to avoid the building 60,

up of such a high .pressure yat that point in the later operations where distortion of dies due to uneven pressure is objectionable. When rudimentary feet are formedi the blank is centered by these feet and the centering `pin is no longer After the central hole has been substantially closed by the pressure of the rst dies; it is reopened to the desired diameter by drilling to remove the stock ter opening, after the swaging step, is shownas circular. `However, in these steps the center opening, before being drilled, is not a true circle because the metal may iiow slightly` diierently from one direction thanfrom the others. Such 75 central hole is'nally reopened by af die or drill to'accommo'date the hands-carrying arbors, such reopening being at the Sametime the blank as shown in Figs. 6 and 6a, is trimmed to provide the" dial shown in Fig; 7. f

The die face formations, shown in Figs'. 9 and 10i-were the result of problems that arose in the use of other formations, before thoseforms were produced, which resulted in deformations of the blank found to be chargeable to the elasticity .of the metal from which the dies were made and which resulted in a higher pressureat certain points and with no direction for the metal under pressure to ilow that would prevent that action on the dies, resulting' in the dial being thicker at the central portion than at the 9 and 3 oclock edges.v By the preliminary operationswhich the dies; shown in Figs. 9 and l0, perform, the metal in the intermediate stages is owed and shifted to positions where the pressure exerted in the final swaging operation will bealmost equal over the` surface of the dial and any distortion of the dies which may occur will be even and without any objectionable result because' the contourof i the finished dial, even though the entire surface may be depressed slightly, will nevertheless be satisfactory.

The radius of the convex face of the upper die shown in Figs. 9 and l2 is less than that of the upper die shown in Figs. l and 13, the curvature of greater radius tending to flow the metal to the side a little further than the curvature of less radius.

A' piny 3l engaging aligning holes in the upper and lower dies situatedv at the 6 oclock end of the diessecures and maintains the alineznent of the dies during operation. The aligning holes in the upper die are slotted to the periphery of vthesame as shown at 31a in Figs. l2 and 13 in' order-to aiord the aligning pin 3| a snug, slightly expanding fit.

.The gradual evolution or development ofthe feet is shown beginning with the rudimentary form 26 shown in Figs. 2a through Fig. 8, the perfected form of -foot appearing as 3E! in Figs. 7 and 8. l

It is very important that at leastthe central portion of the dial be not spaced on its underside from the pillar plate 32, (see Fig. 8) and should lie snugly thereagainst because of the danger of cracking or otherwise injuring the dial by pressure thereon from the hand removing tools when the hands are to be removed, such tool being thrust between the face of the dial and the hands at'the center arbor.

The'shape of the dies which are employed may vary to suit the part or parts which are to be made by the process of this invention, although for purposes of example there has been herein shown and described dies'partioularly useful for producing curved watch dials. The essential principle of the invention, intended to be b-roadly covered hereby, is that of flowing metal of a blank or strip transversely by pressure across the edge of an opening into which it is desired for the metal to ow'in order to obtain a projection on one face of the blank while maintaining an unblemished, homogenous surface on the opposite face of the blank and opposite the projecthe blank to' another. jections arev desired, one shifting operation orv step may suiice, but for projections of greater" length and magnitude, successive steps of shifting or flowing metal `should be resorted to. The` successive steps of forming the-rudimentary'prov jections 26 to the'final finished feet 3@ of desiredy vdiameter andlength depend upon the size' and, shape, of course, of the openings or projection forming matrix lll land the pressure applied by the dies.

Thenopenings I4 in the dies extend i through the thickness thereof, and'fat` no tune `1 does the metal, which subsequently feet, completely ll the openings. Having thus described the invention and manforms the ner in which the same istobe performed, it isA to be understood thattheinvention is .not to be limited to the exactdetails of the description anddisclosure in the drawing herewith', because the same may be modified and varied in numerous Ways within the scope of the present invention,

`and it is desired thatthe invention is not to be limited beyond the scope of What I clairn is: f 1. The method of making a curved watch dial the appended claims.

which e comprises the following steps, forming rudimentary feet on the back of the blank and simultaneously thinning the blank at its central portion,4 working the' rudimentaryfeet and si'- multaneouslythinning' the blank at its 6 and l2 oclock portions by' effecting a owof metal from y these portions toward the central portion, fury' ther working the feet into the desired shape and simultaneously giving the front ofthe blank a convexly curved shape, impressing the track and numerals on the convexly curved front of the blank, and then trimming the' blankinto the desired shape. l

2. 'I'he method of makinga curved Watch dial which comprises the following steps, forming rudimentary feet on the back of the blank and f simultaneously thinning Athe blank at its central 4' portion, `working the rudimentary feetv and simultaneously thinning the blank at its 6 and 12 oclock portions by effecting a flow of metal from these portions toward the central portion, and' further working the feet into the desired shape and simultaneously giving the front of the blank a convexly'curved shape.

3. The method of producing a projection on a metal blank or strip which method includes sub-` jecting a metal blank to a forming pressure and thereby extruding stock from the blank intofa projection forming matrix and simultaneously shifting a portion of the stock transversely completely across the entrance to Athe projection forming matrix from one portion of the blank.

to another, for forming a projection on the blank.

4. The method of producing a projection on a metal blank or strip which method includes subjecting a metal blank to a forming pressure and metal blank or stripwhich includes the' steps `of subjecting a metal blank to pressure therebyv w extrudingstock from the blank into a projection forming matrix and simultaneously shiftingv `thereby extruding stock from the blank into av projection forming matrix and simultaneously stock transversely completely across the entrance to the projection formingv matrix' from onev portion of the blank to another, for Aforming a rudimentary projection' from the stock of a metal blank, and subsequently subjecting the blank to a second pressing operation for completing the shapey of the rudimentary projection.

6. A method of making curved Watch dials that includes the acts of taking a metal-plate blank land subjecting it on opposite sides to pressure surfaces thereby shaping the blank with a thickness that diminishes from the central portion to the opposite edges thereof, forming said blank into a convexe-concave conguration, and extruding attaching fe'et therefrom,

7. A step in the method of making a Watch dial, as setforth in claim 6, wherein the blank is subjectedy to a forming pressure thereby shifting-the stock from the 6 and 12 oclock areas to- Ward the center, three, and nine axis, and also iiowing metal into feet forming matrices.

8. In a method of producinga projection on a metal blank or strip which method includes the application of a series of forming pressures, centering a metal blank and subjecting it to an initial forming pressure thereby shifting some of the stock of the blank transversely completely across an opening in a projection forming matrix and simultaneously extruding a projection on the blank, then centering the blank by means of theI projection thus formed and further working the blank by a second forming pressure.

9. The method of producing a projection on/a thin dial by several pressure steps which method comprise applying one pressure step thereto thereby shifting metal from one portion to another to form comparatively thick and thin areas in said dial, applying a second pressure step to said dial near the thickened areas and shifting some of said stock in the thickened area completely across a projection forming matrix and also extruding certain of said metal into said matrix.

10. A method of forming a projection on a thin dial as set forth in claim 9 wherein the metal is `further Worked lthereby extruding a sufli-A cient quantity of metal to produce a substantial projection.

1l. The method of forming projections on a thin blank which method comprises shifting a portion of theI stock of the blank transversely completely across a projection forming matrix and simultaneously so extruding another portion of said stock from the one side of the blank into the projection forming .matrix as to leave the other side ofthe blank smooth and free of indentations thereof. ,Y

12. The method of making a curved Watch dial Which comprises the following steps: shifting the metal from one area to another to ,form thick and thin portions, further shifting the metal from the comparatively thick portion of the dial to the thin portion and simultaneously forming rudimentary feet, and further shifting the metal in the dial to give the dial its come pleted shape and simultaneously completing the shaping of the feet.

ALVIN LODGE.

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