US3732686A

US3732686A - Watch movement including alarm mechanism

Info

Publication number: US3732686A
Application number: US00279298A
Authority: US
Inventors: R Zaugg
Original assignee: A Schild SA
Current assignee: A Schild SA
Priority date: 1972-08-10
Filing date: 1972-08-10
Publication date: 1973-05-15
Anticipated expiration: 1990-05-15

Abstract

A watch movement comprising an alarm mechanism provided with a vibrating membrane located above the bottom plate, characterized in that the vibrating membrane is an annular plate resting on a supporting ring which is fastened to the bottom plate and pressing against the dial.

Description

United States Patent 1 Zaugg 1 May 15, 1973 [54] WATCH MOVEMENT INCLUDING [56] References Cited ALARM MECHANISM UNITED STATES PATENTS [75] Inventor: Roland Zaugg, Grenchen, Switzerland 2,644,294 7/1953 Ditisheim ..58/57.5 2,786,326 3/1957 Junghans et a1. ..58/57.5 [73] Assignee: A. Schild S.A., Grenchen (Canton f soleure), Switzerland Primary Examiner- George H. Miller, Jr. Attorney-Richard K. Stevens, et al. [22] Filed: Aug. 10, 1972 [57] ABSTRACT [21] Appl. No.: 279,298

A watch movement comprising an alarm mechamsm provided with a vibrating membrane located above the [52] U.S. Cl ..58/57.5 bottom plate, characterized in that the vibrating men [51] Int. Cl. ..G04b 23/12 brane is an annular plate resting on a supporting ring [58] Field of Search ..58/16-22.9,57.5,58 wh ch is fastened to the bottom plate and pressing against the dial.

8 Claims, 2 Drawing Figures 1 WATCH MOVEMENT INCLUDING ALARM MECHANISM The acoustic signal in alarm wrist-watches generally is generated by a hammer striking a pin fastened to the inside of the case back. This pin however becomes an obstacle if one wishes to make a watch in which the movement is provided with a self-winding mechanism. Most of the self-winding devices presently comprise a rewinding weight or mass performing complete rotations about its axis. When the oscillating mass is located on the reverse side of the movement, that is above the bridges, it is advantageous that it should pivot about the movements axis, but the alarm pin projecting from the back prevents use of such and compels either shifting the axis of the oscillating mass or use of a mass with restricted excursions. Now both solutions entail drawbacks: either poor functioning of the oscillating mass or else an increase of the movements dimensions beyond the minimum that would be otherwise possible.

In order to provide clearance for the back side of the movement, the vibrating membranes of alarm watch movements have been placed above the bottom plate. In certain known alarm watch movements, the vibrating membrane is bell-shaped and directly constitutes the dial. However, in order to improve its acoustic properties, this membrane is provided with a lateral wall that is bent over on the side of the movement, and there remains a visible joint prejudicial to the esthetic qualities of the watchs visible side between the cases flange and the outer part of the dial. In other cases, the vibrating plate constituting the dial is supported by a peripheral ring fastened to the movement, but this solution too entails shortcomings as regards esthetics. On the other hand, and with increasing frequency, the dials display the hour-symbols in relief or are'provided with windows, and hence it is difficult to impart to them the required acoustic properties.

Alarm watch movements are also known in which a bell-shaped vibrating plate extends between the movements bottom plate and the dial. This plate is fixed to the bottom plate by its center and one must maintain sufficient space between the vibrating membrane and the dial in order to avoid any interaction between these two latter components.

Besides the drawbacks mentioned, these known devices further suffer from not being suitable when an indicating organ such as a date ring moves underneath the dial in such a fashion that its readings are visible in a window.

The purpose of the present invention is to resolve this problem by proposing an arrangement of the vibrating membrane that will allow easy assembly without furthermore requiring excessive space with respect to height and which also allows assembling a date ring or any other calendar organ underneath the dial.

In order to achieve this goal, the present invention proposes a watch movement comprising an alarm provided with a vibrating membrane located above the bottom plate and characterized in that the vibrating membrane is an annular plate supported by a support ring which is fastened to the bottom plate and pressing against the dial.

The attached drawing illustrates an embodiment of the object of theinvention, in which:

FIG. I is a fragmentary axial section; and

FIG. 2 is a fragmentary top view from the bridges, these latter having been removed.

The wrist-watch movement partially shown in the drawing is provided with an oscillating-mass selfwinding mechanism (not shown), where the mass oscillates above the bridges at the center of the movement. A dial 2 is fastened above bottom plate'l. Only one of the bridges 3 ensuring the rotation of the various organs of the alarm mechanism is shown. The movement further is provided with a calendar mechanism comprising a date ring 4 located underneath the dial so that the dates will appear in a window (not shown). This date ring is kept in place by a plate 5 which is fastened to the bottom plate and its inner toothed edge 6 surrounds a circular shoulder fashioned in the upper side of bottom plate 1. The described movement also comprises a day indicating organ made up of a disc 7, which is also located underneath the dial and inside ring 4, and of a day-star 8 which is actuated by means not shown. At the center of the movement, dial 2 is provided with an opening 9 through which pass the coaxial bushings of an alarm wheel 10, of the hour wheel 11 and of cannon-pinion 12 as well as the seconds staff 13; all these wheel-and-pinions support hands (not shown) moving above the dial 2.

The drawing does not show the alarm engaging mechanism nor that for the time-setting of wheel 10, nor shall these be described here in detail. Those parts of the movement are of conventional construction and present no singularities. The alarm wheel 10 comprises a disc extending above that of the hour-wheel 11 and which may be made to rotate by external means and which further includes an organ capable of triggering the striking mechanism when the positions of the hour wheel and of the alarm wheel coincide.

The striking mechanism comprises a barrel 14 located in the movement frame between the bottom plate and a bridge and in which there is a striking-mechanism spring mechanism that may be rewound by means which are known per se. The peripheral toothing 15 of barrel l4 works in concert with pinion 16 of strikingwheel 17 which rotates between a bearing 18 located in bottom plate 1 and a bearing 41 force-fitted into bridge 3. The striking hammer 19 is made up of a fairly thick metallic mass riveted by means of three elements 20 onto plate 21 which constitutes the pallet working in concert with the striking wheel 17. This pallet is force-fitted onto an arbor 22 which is assembled between the

bearings

23 and 24 of which the former is fastened to the bottom plate and the latter to bridge 3. The pallet is a stamped-out or cut-out plate with two beaks 25 and 26. Beak 25 is an exit beak and beak 26 an entry beak, both working in concert with teeth 27 of wheel 17. For the embodiment shown in the drawing, the sense of rotation of wheel 17 when the striking mechanism has been released is opposite to the sense of the watch's hands. The energy for rotation is provided by the spring in the barrel l4, and in the course of this rotation, the pallet is made to oscillate alternately between the position shown in the drawing and the other extreme position when beak 26 is touching by its tip one of the teeth 27.

Pallet 21 is provided at its center with an elongated opening 28 that extends normally to the straight line fromthe center of this opening to the pallets pivoting axis. On the other hand, hammer 19 is provided with a flat-bottom bed 29 of the same'shape as opening 28 and coinciding with it. The bed and the opening are so made that after movement assembly, they are opposite a clearance 30 in the bottom plate.

Bed 29 and

openings

28 and 30 allow connecting the vibrating membrane, generating the striking mechanismss sound, with hammer 19. This membrane is made of a plane annular plate 31, which may be of hardened steel or of a similar material, several tenths of a mm thick and of which the outer edge 32 is folded over upwards by 90 and force-fitted into an annulus 33 the inner side of which is appropriately provided with an annular recess 34 for that purpose. Ring 33 supporting membrane 31 is placed in a peripheral recess 35 in the bottom plate above the latters thread. Ring 33 further is kept in place axially by the edge of dial 2. In this fashion, membrane 31 is mounted above the bottom plate near the periphery of the movement. It is provided with openings 36 at two points on its periphery, the dial feed 37 of dial 2 loosely passing through these openings. The dial feet penetrate into bore holes in the bottom plate and are fastened by conventional means. Ring 33 supporting annular plate 31 is assembled together with the latter on the bottom plate before assembly of date ring 4, the annular plate 31 extending between the bottom plate and ring 4. In order to ensure the proper orientation of membrane 31 so that openings 36 and pin 40 be properly positioned, ring 33 is provided with a notch 38 at a point on its periphery which surrounds the top of a peg 39 that is force-fitted into a bottom plate bore hole. In order to ensure a corresponding orientation of annular plate 31 with respect to ring 33, the annular plate folded-over edge 32 may be provided at a point of its periphery with a lug entering the corresponding opening provided by ring 33 (lug not shown). On the other hand, in lieu of the rim 32 being force-fitted along its entire annular surface into the inner side of ring 33, it might also be provided with regularly distributed hollows along its periphery, for instance four hollows leaving between them only four sections of contact surfaces between rim 32 and ring 33. Such an arrangement allows easier acoustic energy propagation.

Membrane 31 is set into vibration by the intermediary of a cylindrically shaped pin 40 which is set in that side of membrane 31 facing the bottom plate and which is so located that it will pass through the

openings

30 and 28 of the bottom plate and of the pallet 21 and will penetrate into bed 29. The dimensions of this bed, the pallet and pin 40 are so fashioned and selected that the oscillating pallet motions under the action of wheel 17 at the time of striking-mechanism triggering are such that the two extremities of bed 29 alternately strike pin 40 in each of the pallets extreme positions. In this man ner a striking-mechanism has been achieved that offers several advantages. These are as follows:

1. The striking-mechanism is independent of the case. The latter may be of conventional construction and the difficulties encountered for the mechanisms using the case-back as a vibrating membrane in order to precisely position the membrane-actuating pin are thus eliminated. The vibrating membrane and the hammer being incorporated into the movement, exact positioning of all parts is thus achieved in overall assembly.

2. The movement may be provided with any conventional self-winding mechanism since the strikingmechanism is wholly located towards the bottom plate.

3. The sound volume of the signals emitted by the alarm is independent of the manner in which the watch is fastened to the wrist of the wearer. Because the vibrating membrane is some distance from the wrist and because it is located immediately underneath the dial, it radiates the emitted sounds more effectively than do prior alarm wrist-watches.

4. As seen in the drawing, the location of the membrane between dial and bottom plate practically entails no increase in movement thickness or diameter.

Thus it was feasible to incorporate the described mechanism into a self-winding watch movement which comprised, besides the alarm mechanism, a date ring and a day indicator, without thereby incurring an appreciable increase in movement dimensions.

What is claimed is:

1. A watch movement containing an alarm mechanism, comprising: a bottom plate; a dial assembly; a support ring fastened to said bottom plate and pressing against said dial assembly; and a vibrating membrane for said alarm mechanism comprising an annular plate resting on said supporting ring and disposed above said bottom plate.

2. A watch movement according to claim 1, further comprising: a striking mechanism hammer set inside the frame of said watch movement; a pin supported by said annular plate membrane and passing through an opening in said bottom plate; and means operatively connecting said pin with said striking mechanism.

3. A watch movement according to claim 2, wherein the striking-mechanism hammer is fastened to a pallet which is actuated by a striking-mechanism wheel and which is provided with an elongated opening pene trated by said pin, the length of said opening being such that its two ends alternately strike said pin when the pallet oscillates.

4. A watch movement according to claim 1, further comprising a calendar mechanism; wherein said support ring extends around the annular plate membrane and a date ring for said calender mechanism is mounted by its inner edge on said bottom plate and extends between said membrane and said dial.

5. A watch movement according to claim 4, wherein the date ring is kept in place by a fixed component covering its inner edge.

6. A watch movement according to claim 5, further comprising a day indicating organ comprising an indicating disc fastened to a day-star, said indicating disc extending between said fixed component and the dial at the height of that part of the date ring which is located between the vibrating membrane and the dial.

7. A watch movement according to claim 4, wherein said annular plate membrane is force-fitted into an annular recess in the inner side of said support ring and that the support ring is tightly fitted in place between the outer edge of said bottom plate and the dial.

8. A watch movement according to claim 7, wherein said annular plate membrane is provided with openings through which pass the dial-feet of said dial assembly which themselves engage bore holes in said bottom plate.

Claims

3. A watch movement according to claim 2, wherein the striking-mechanism hammer is fastened to a pallet which is actuated by a striking-mechanism wheel and which is provided with an elongated opening penetrated by said pin, the length of said opening being such that its two ends alternately strike said pin when the pallet oscillates.