US2405928A - Adjustable watertight and dusttight watch crown - Google Patents

Description

W. FEURER ADJUSTABLE WATERTIGHT AND DUSTTIGHT WATCH CROWN Filed Dec. 9, 1944 Patented Aug. 13, 1946 ADJUSTABLE WATERTIGHT AND DUSTTIGHT WATCH CROWN Walther Feurer, J ac son Heights, N. Y., assignor, by mesnc assignments, to Feurer Bros, Inc., New York, N. Y., a corporation of New York Application December 9, 1944, Serial No. 567,493

2 Claims.

The invention herein disclosed relates to watch crowns.

Special objects of the invention are to provide a close fitting, dust and water-tight crown construction which will not depend upon springs or the like for keeping it tight and which may be readily adjusted at any time to take up any wear and restore it to the desired water-tight and dusttight condition.

Other objects of the invention are to provide a crown construction of the character mentioned which will not interfere in any way with the mounting or unmounting of the crown and which need not increase the overall ize of the crown structure.

Further objects are to provide a water-tight and dust-tight crown connection which will not interfere in any way with either the winding or the setting of the watch and which will maintain a proper seal during any or all such operations.

Another object of the invention is to provide a connection of the nature indicated which will permit use of the same size crown with watchcase tubes of different diameters.

Other desirable objects and the novel features by which the purposes of the invention are attained are set forth or will appear in the course of the following specification.

The drawing accompanying and forming part of the specification illustrates two different embodiments of the invention. Structure, however, may be modified and changed as regards these illustrations, all within the true intent and broad scope of the invention as hereinafter defined and claimed.

Fig. 1 is a broken sectional view of one form of the invention; and

Fig. 2 is a similar view of a slightly difierent form of the invention.

In both views the band or ring of a watchcase is indicated at 5, having the usual projecting fixed tube 6 for the stem I.

In both illustrated embodiments the crown 8 is of hollow construction, having a screw thread-.

ed post 9 for detachable engagement with the stem.

The water-tight, dust-tight and substantially air-tight connection is effected in both forms of the invention shown, by a gasket or washer Ii of suitable packing material such as rubber or the like, compressibly held between annular guides Within the crown in sealing engagement between the rim of the crown and the exterior smooth surface of the tube.

In the Fig. 1 form the inner guide is in the shape of an annular washer II loosely seated in the back of the crown and having a central pas-- sage I2 freely surrounding the tube.

Similarly, in the first form, the outer guide also is a loose fitting washer I2 disposed in the hollow of the crown over the outer face of the compressible packing and having a guide opening I4 freely receiving the tube.

Compression is applied to the packing in both forms of the invention by a ring or annular form of nut I5 screwed into the hollow of the crown over the outer packing washer I3. This ring is shown as having notches or grooves it in the outer face of the same for engagement by a suitable spanner or other tool. This nut is shown as hav ing a central opening I! appreciably larger than the watch tube, enabling its use on watchcases having tubes of different diameter.

The interior of the crown may be screw threaded the full depth, as indicated, or only for that portion which might ever be reached by the nut in adjusting tension on the packing.

In Fig. 2 the inner guide is constituted by the inner or back wall I8 of the crown. The use of this back wall in place of a separate inner washer necessitates the turning of an annular channel I9 about the base of the post to receive the inner end of the tube.

Such construction usually requires the use of an annular or circular cutter. This is a separate, additional operation, requiring, particularly in small crowns, a considerable degree of care and skill.

For the reasons mentioned, the first form illustrated may be preferred where the cavity in the back of the crown for receiving the extreme end portion of the tube is provided by simply turning or boring a conical depression 20 at the back wall of the crown.

For other reasons the Fig. 2 form with the solid or thicker back Wall and without the inner washer forming an extra part, may be preferred.

In the second form, the edge 2| of the annular out about the base of the post serves is a, uide in the same manner as the opening I2 in the inner washer of the Fig. 1 construction.

The outer and inner guides provided by the outer washers I3 and the inner washer I I or back wall I8 facilitate the engagement of the crown over and its removal from the tube and avoid injury from any extreme side pressure on the crown. These guides remain in effective position in both the winding and the setting positions of the crown. This point is illustrated in Fig. 1 where broken lines are interposed to indicate the shifted position of the inner guide in the setting position of the crown.

The parts are readily assembled. The degree of compression required may be tested by turning the nut tight into the crown and then slipping the crown over the tube to sense the degree of engagement of the packing with the tube. This tension may be increased or diminished before the crown is finally mounted. At any time the connection may be quickly adjusted for wear by simply unscrewing the crown from the stem and tightening the nut more or less. Any tightening or loosening of the nut does not twist-the packing or otherwise disturb the parts, as" the not has a smooth slide fit over the face of the outer washer.

By provision of difierent diameter washers and packings the same crowns and nuts may be used for different diameter tubes, the larger internal diameter of such nuts permitting of such use.

In all positions of use the crown is both sealed and guided. The structure accomplishing these results is entirely concealed and protected; and yet is quickly accessible if any adjustments are required, Furthermore, the structure isof a universal design in that the same size, crown and clamp nut may be applied to watchcases of different styles and sizes.

What is claimed is:

1. A water-tight and dust-tight crown construction comprising in combination with a watchcasehaving axfixed projectingtube, a hollow crown having an internally screw threaded annular side wall surrounding the tube and a central, stem engaging post freely entered in the tube, inner and outer guides positioned in the crown to surround the tube in both the setting and the winding positions of the crown, an annular packing compressiby held between said inner and outer guides in position engaging the annular side wall of the crown and the outer surface of the tube, the outer one of said guides being free of both the tube and the crown, and an annular nut adjustably engaged with said screw threaded side wall of the crown, over said outer guide, said nut surrounding but being free of said tube.

2. A water-tight and dust-tight crown construction comprising in combination with a watchcase having a fixed projecting tube, a hol- 10w crown having an internally screw threaded annular side wall surrounding the tube and a central, stem engaging post freely entered in the tube,rinner and outer guides positioned in the crown to surround the tube in both the setting and the winding positions of the crown, an annular packing compressibly held between said inner and outer guides in position engaging the annular side wall of the crown and the. outer surface of the tube, the outer one of said guides being, free of both the tube and the crown, and an annular nut .adjustably engaged with said screw threaded side wall of the crown, over said outer guide, said nut surrounding but being freeof said-

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