US2482583A

US2482583A - Waterproof watch crown

Info

Publication number: US2482583A
Application number: US81858A
Authority: US
Inventors: Charles B Greenberg
Original assignee: ALGREN WATCH FINDINGS CO Inc
Current assignee: ALGREN WATCH FINDINGS Co Inc
Priority date: 1949-03-17
Filing date: 1949-03-17
Publication date: 1949-09-20
Anticipated expiration: 1966-09-20

Description

Sept- 1949- c. B. GREENBERG WATERPROOF WATCH CROWN Filed March 17, 1949 I u 1 w [Zfll'f fieem ezy I N V EN TOR.

ATTORNEY Patented Sept. 20, 1949 fihai les B. Greenberg, New-ork,;N-. Y., ass'ign or :A'lig'r'en Watch Findings ooflnamew'york,

ApplicationMare'h H, 1949,7Serial2No. 81:858

invention relatesto watch crowns, and more particularly, to waterproof watch crowns editable for use with watch cases having protecti tubes.

application 'for apatent is acontinuatienj'in part of my application entitled Waterproof watchfcr'owns;

no inoisture or dust protection is provided.-

variation 'is due to non unifcrmity in the s'i'ze'hf tlie'wa't'ch case'tubes and the bores-of the crown packing, and to variations-in thaphyslcal properties of the packing,

istherefore an object of this invention to provide a waterproof --c'1own whose "fit with a watch case tube can be regulated or adjusted to give "any definite 'desired degree of tightness without e angi ng any of the vdlmensionsofthe eieine'ntscfthe crown or of the watch ease'tube.

Examinations of waterproof crowns of the usueronstrueuon have shown'that non-uniform gripping lprssu're between the contacting faces hecfownpacking and the watch case tube fiequenuy "result in 'a packing "being torn apart,

split "or "e'iicessively'wor'n or abraded and ultimately results in the crown losing its waterproofing characteristic.

"It is an object of 'this invention therefore "to provide means causing the crown packing to giip'th'e watchcase tube with uniform'intensity th'roug'houttheir entire contacting surfaces,

A shallow, low or small crown "has many artistic advantages over a high, big crown and therefore is in ."fa'regreater demand. l lowever,

shallow and small waterproof crowns used with tiibe type watch cases do not seal-eifectively-lthe case a'gains't moisture, etc., because of the small areaoi coiita'etbetween the crown packing arid the when case tube.

Therefore, an object of the invention is "to form a large, high crown presenting or .givi'n'g the appearance of (a small shallow crown '"and 'so having the ;'artistic advantages of "the small crown and the ephySiGa]. advantages of 'the larg'e crown.

Another object is to form a shallow or sina'll waterproof crown with a relativly great areaot sealing eontact between the crown .paliing and the watch case-tube.

. A small waterproof crown which hugs, 'or-res'ts close to -its-case=is especially difiicult to'mo'v'e'or pull out to allow esetting of the watch becaus of*-the=tight-gr ip between the crown packing and thecase and the inability-toobtain a s'eci'ireg rip on=the -crown. "'The creation of a finger fgriplb'y the use-of a larger crown or by positioning the crown away from the case results'inan unsightly appearing watch and the separated 'o rset 0 ft crown presents aprdblem of increased 'thidiie and bending. 7 'Iherefore, an object of this invention "to forma waterproof crown which is "petitea'ndis positioned hugging'the case and alsowhich can be -g;ripped easily and so moved to a setting position.

-A further object is to 'forrn'a 'wate'rproo'fwateh crown of a :minimum of elements which are easily and simply assembled and to .producen sightly and easily manipulated 'crown 'c'ap'ab'le withstanding excessive wear and 'cons'ider'atile abuse. A

'I-accomplish these and other "obiectsby forming my crown of a crown"fr'am'e, a fianged'tiibe, and amesilient annular "pack'ingthe crownframe having'acrown Welland aw-ihdi'ng post therein, the flanged tube"'bein'g "fQrce fitteH into the wet andengaging the sides'there'of substantially "for their entire surface area, the 'flange of "the "tube beingflpositioned at the outer end of the tribe and extendinginwardly toward the windingpost-of the well and the resilient annularvpacking being longer, :When not underpressure, than the depth of the well or "tube and"being'hld'ihposition, under pressure, in the well and about its winding post, by the flanged tube 'where'bythe depth positioning of the tube-inthe well deter mines the annular diameter '-of the resilient .packing and the intensity of its grip on the watch rcase -tiilie. AI positioning of the'tube withits outer end pro;

3 truding from the well results in an excess of contact of the packing with the watch case tube and provides a finger grip for setting the watch even though the crown is shallow.

For further comprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description, the accompanying drawings and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure;

Fig. 1 is a perspective view of a waterproof watch crown embodying the invention and showing its crown frame, flanged tube, and resilient packing in full line and a watch case tube in dashed line.

Fig. 2 is a sectional view in two parts, shown,

on the left side, a crown with its tube'flush with its crown frame and with the resilient packing under a maximum pressure, and on the right side, a crown with its tube extending above the crown frame and the resilient packing under less than maximum pressure.

Fig. 3 is a fragmentary view of the crown shown in Fig. 2, right side, positioned on a watch (shown in dashed line).

In the drawings and in the specification, in which like numbers represent similar elements, a waterproof watch crown I8, is shown comprised of a crown frame H, flanged tube l2 and a resilient packing i3.

The crown frame I! is cup-shaped, having an opening or well I 4 provided with side walls [5, an a bottom I 6. axially in the well, is provided with female threads suitable for engaging the threads of a watch movement stem (not shown).

The resilient packing i3 is positioned in the well about the post and the flanged tube is force fitted into the well with the flange l8 extending inwardly toward the post and exerting pressure on the packing. The sides of the tube which extend substantially to the bottom of the well are in intimate engagement with substantially the total surface area of the walls of the well, so that while the total force of the engagement is great, the unit pressure between the contacting faces is small. This permits the flanged tube to be inserted and gripped by the cup walls with a mini- 7 More than the normal clearance between the watch case tube and the flange is needed as there is a tendency for a trailing edge 18 of the resilient washer to adhere to the watch case tube when the crown is moved away from the watch in the setting operation and this edge becomes wedged between the watch case tube and the inner edge 20 of the flange. The return of the crown to the watch does not release the caught edge I9. This results in an excessive and non uniform pressure by the packing and causes abnormal wear and makes winding difficult.

The pressure, created by the flange pushing against the packing, is transmitted longitudinally and laterally throughout the resilient packing and causes the packing to grip the side walls of A winding post l1, positioned '75 setting.

the tube, the bottom of the well and the watch case tube (shown in dashed line) which is inserted into the well, when the watch stem is threaded into the crown post. Thus the packing forms a closure about the watch case tube and so shuts and seals off the watch case opening through which the watch stem extends.

During the winding operation of a watch provided with the crown ID, a twisting or torque is developed in the resilient packing as the packing rotates with the crown while gripping the watch case tube which remains stationary, To carry and transmit this torque properly, the packing must grip the watch case tube uniformly throughout their area of contact and also the packing must grip the side walls of the flanged tube uniformly throughout their area of contact, and both areas of contact must extend substantially for the full height and depth of the crown well. Without the uniform pressure and the full areas of contact, there is a tendency for the packing to r be twisted and torn. This occurs when one end of the packing grips the watch case tube and the other end grips the flanged tube of the crown. In addition, there is a tendency where there is nonuniform pressure for the packing to wear unevenly and for the crown to lose its waterproofing characteristic. Uniform pressure throughout the packing is obtained by providing substantial encasement of the packing within the tube of the crown and that all the pressure supplied to the packing be in a direction parallel to the axis of the tube.

The total pressure, or the grip of the crown packing about the watch case tube must be sumcient to provide an effective waterproof seal but must not be so large as to prevent the Winding and setting of the watch. The ultimate location of the flange of the crown tube, which creates the packing pressure, therefore, becomes highly important. As all batches of resilient packing are not of exactly the same resiliency and the resultant packing therefrom cannot have exactly the same inside and outside diameters and as the specifications of all watch companies for watches of the same size are not the same for their watch tube elements a standard location for the flange cannot be set to give the required pressure and result in a crown having a good waterproof char acteristic and also being easily wound and set.

In making the crown [0, the variations in the physical properties of the packing and the dimen sional variations in the watch case tubes are considered and the depth to which the flanged tube is inserted in the crown well is appropriately cor rected to correspond to the diiferent specifications. Thus, without changing any of the crown frame, flanged tube or resilient packing basic dimensions, a crown is formed which can be adapted to function perfectly with many sizes of watch case tubes.

The crown 2| (left side of Fig. 2) is shown with its flanged tube 22 inserted into the crown well so far that the upper edge 23 of the flange is flush with the top of the crown frame, while in the crown in (right hand side of Fig. 2) the outer face 24 of the flange of the tube !2 extends above the crown frame H.

The setting operation of a watch is made easy by the crown I B as its extending flange is in close proximity to the watch case, while the crown frame rests slightly away from the case and thereby provides an opening into which a finger nail can be inserted to retract the crown for It should be noted that the area of contact between the resilient packing and the watch case tube is greater in the crown it than in the crown 2i and as a result, the crown I a) will have a better waterproofing characteristic than the crown 2!. A crown developed with an extending flanged tube can therefore be made with a good waterproofing characteristic and having its frame of a low height or shallow and so of a sightly and delicate appearance. The extending flanged tube, therefore, provides a finger grip to aid in setting the watch and. permits the construction of a shallower, lower and neater appearing crown.

Although I have shown and described my waterproof crown in its main form and what could possibly be termed a variation, many other variations are possible without departing from the spirit and scope of the ideas conveyed in the drawing and description; therefore, I desire to cover all modifications, forms and embodiments of my invention coming within the scope and language of any and all of the claims here following.

Having thus described my invention, what I claim as new and desire to secure by United. States Letters Patent is:

1. In a watch crown suitable for use with a tube type watch case, a crown frame having a crown well, a resilient annular packing resting in said well and a tube having an inwardly extending flange, the tube substantially positioned in the well and gripping the major portion of its wall and the flange exerting pressure on the resilient packing, whereby the packing grips and forms a seal when the crown is applied to the tube of a watch case.

2. In a crown as described in claim 1, having its flange extending over only a substantial part of the resilient packing whereby sufficient space is provided between the flange of the crown and the watch case tube to prevent the packing from becoming wedged therebetween.

3. In a watch crown suitable for use with a tube type watch case, a crown frame having a crown well, a resilient annular packing resting partially in said well and a flanged tube having an inwardly extending flange, the tube substan tially positioned in the well and gripping a major portion of its wall and extending above the upper edge of the crown frame and its flange exerting pressure on the resilient packing, whereby the packing grips and forms a seal when the crown is applied to the tube of a watch case.

In a watch crown suitable for use with a tube type watch case, a crown frame having a crown well, a resilient annular packing resting in said well and a tube having an inwardly extending flange, the tube substantially positioned in the well with its lower end spaced from the bottom of the crown well and said tube exerting a light unit pressure against the well wall and the flange of the tube pressing against the resilient packing, whereby the position of the tube in the well can be accurately adjusted to vary the pressure in the resilient packing.

5. In a watch crown suitable for use with a tube type watch case, a crown frame, a tube and a resilient annular unitary washer, the crown frame having a crown well, the tube having an inwardly extending flange and the tube being positioned substantially in the well and gripping the major portion of its wall and the washer being positioned between and exerting pressure against the well bottom and the tube flange thereby creating an internal pressure throughout the washer.

CHARLES B. GREENBERG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,377,625 Greenberg June 5, 1945 FOREIGN PATENTS Number Country Date 159,714 Switzerland Apr. 1, 1933