Watertight Alarm Wristwatch

Abstract

The sounds of the alarm are produced by a membrane exposed to the atmosphere and against which strikes a vibrating blade located in a recess provided in the outer surface of a piece which constitutes a section of an envelope tightly surrounding the watch movement, the latter being located in a recess provided in the inner surface of said piece.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to watertight alarm wristwatches and, in particular, to such wristwatches which are provided with an electrical alarm device, all the parts of which are located in the watch case.

2. Description of the Prior Art

A watch of the type indicated above has already been proposed. In that watch the sounds were produced by a membrane which could be secured to the watch case bottom so as to extend across an opening of the latter. The membrane was caused to vibrate and to produce a sound by means of a member comprising an armature and a spring blade carrying that armature. This blade was itself caused to vibrate at a natural frequency and thus to strike against the membrane by means of an electrodynamic transducer fed by a miniature battery also located in the watch case.

Ensuring a tight closure of the casing of that known watch has already been considered. This was relatively easy, because the membrane needed only tightly close the aperture of the casing through which the membrane was exposed to the atmosphere for ensuring the free propagation of the sounds.

The tightness of the casing of that known watch was, however, precarious. In the event the watch is submitted to an overpressure, for instance when it is under water, the membrane could be torn thus causing the complete immersion of the watch movement. The membrane which has only a reduced mechanical resistance could also be torn by an agent different from an overpressure. In such an event the slightest contact of the watch with water already exposes the watch movement to be immersed.

A remedy to that drawback has also been proposed. It consists in using the watch glass as a membrane producing the audible sounds of the alarm.

This last solution is, however, very special because it requires the passage of a rod through the dial thus jeopardizing the aesthetic effect of the watch and, moreover, constituting a hindrance that prevents the watch hands from extending over the whole visible surface of the dial.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a watertight alarm wristwatch in which the watch movement is still protected even if the membrane producing the sounds becomes torn for any reason.

A more specific object of the invention consists in providing a watertight envelope surrounding the watch movement, that envelope having a section, the outer surface of which is provided with a recess in which at least the vibrating member striking against the membrane is accommodated.

Further objects of the invention will become apparent in the course of the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Three embodiments of the watch according to the invention are represented diagrammatically and by way of example in the accompanying drawings in which:

FIG. 1 is a plan view of the first embodiment, the bezel, the glass, the hands and the dial having been removed;

FIG. 2 is a perspective view on a smaller scale of a piece of FIG. 1;

FIG. 3 is a cross section on a larger scale along line III-III of FIG. 1;

FIG. 4 is a part sectional view similar to that of FIG. 3 along line IV-IV of FIG. 1;

FIG. 5 is a cross section of the second embodiment similar to that of FIG. 3; and

FIG. 6 is a part sectional view of the third embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The casing of the watch represented in FIGS. 1 to 4 has a square shape with rounded corners. The movement 1 of that watch has a rectangular shape with arcuate sides. It is a usual movement provided with a spring motor located in a barrel and with a mechanical escapement. A switching device 2 is mounted on movement 1 in order to switch on the alarm. That switching device comprises a metallic disc 3 carrying an arm 4 extending radially outwards and made integral with a tubular projection 5 (FIG. 3) journaled in the central opening of dial 6. Disc 3 can thus rotate coaxially to the hour wheel 7 carrying the hour hand 8, to the cannon pinion carrying the minute hand 9 and to the shaft carrying the seconds hand 10. The tubular projection 5 which carries the alarm hand 11 has a diameter large enough in order to avoid any contact either with the sleeve of the hour hand 8 or with the tubular projection on which that sleeve is set. Arm 4 constitutes one terminal of the switch provided for switching on the alarm. Electrical current is led to that terminal through the dial 6 which is metallic and which is completely insulated from the ground mass including the watch movement 1 and the watch case. The electrical contact between the dial 6 and the metallic piece (3 to 5) is assured by a thin metallic and waved spacer ring 12 located between dial 6 and disc 3, the waves of that ring alternately bearing against either one of those two elements. To ensure the insulation of the metallic piece (3 to 5) with respect to the watch movement 1, the disc 3 and its arm 4 are embedded in a body member 13 made out of an insulating plastic. A toothing 14 is provided at the periphery of member 13 for allowing the same to be driven in rotation in a manner described hereinafter. An annular groove 15 coaxial to projection 5 is provided in the surface of member 13 directed towards movement 1. The depth of groove 15 is chosen in such a manner that a radially extending narrow projection of arm 4 is flush with the bottom of groove 15. The second terminal of switch 2 is carried by the hour wheel 7. It is constituted by a resilient arm 16 made integral with a sleeve 17 set on the tubular projection of wheel 7. An embossing 18 is formed at the end of arm 16 and the latter is bent in such a manner as to cause embossing 18 to bear against the bottom of groove 15.

When the watch is normally running, member 13 remains at rest so that the hour wheel 7 moves arm 16 so as to cause the embossing 18 thereof to slide along the bottom of groove 15. At the exact moment at which embossing 18 comes in contact with the projection of arm 4 which is flush with the bottom of groove 15, moment at which the watch hands 8, 9 indicate the same time as the alarm hand 11, the switch which is controlled by the watch movement, is closed. The width of the projection of arm 4 which is flush with the bottom of groove 15 can be reduced to such an extent that the electrical contact thus established between the dial 6 and the ground mass including the movement 1 only remains closed during 10 minutes when the watch is normally running and provided that no other switch be actuated by the watch carrier for stopping the alarm.

The position of the alarm hand 11 can be set from outside the watch case by means of a setting mechanism represented in FIGS. 1 and 4. This mechanism comprises an intermediate wheel 19 pivotally mounted on an encasing member 20 of movement 1 by means of a screw 21 provided with a bearing surface. Member 20 which is represented in perspective in FIG. 2 is provided with a recess 22 having the same contour as movement 1. A shoulder 23 provided in recess 22 serves as a bearing surface for a peripheral rim of the base plate of movement 1. A shallow recess 24 communicating with recess 22 serves as a housing for wheel 19 provided for setting the alarm hand 11. As shown in FIG. 4 recess 24 is, however, deep enough in order to prevent wheel 19 and its fixing screw 21 from coming in contact with dial 6 which is circular and extends within a recess 25 of member 20. FIG. 1 shows that wheel 19 is meshing with toothing 14 of member 13 so that the latter will be driven in rotation together with the alarm hand 11 upon rotating wheel 19. The latter can itself be driven in rotation in the same manner as the crown wheel of the usual manually winding mechanism of the spring motor of the watch, i.e., by means of a pinion 26 idly mounted on a bearing surface of a setting stem 27. For that purpose pinion 26 carries teeth 28 extending radially outwards and meshing with wheel 19 as well as ratchet teeth 29 extending in an axial direction and being capable of meshing with a corresponding toothing of a clutch wheel 30 upon shifting the same along stem 26. Wheel 30 is set on a square portion 31 of stem 27 in order to secure the same to the stem for rotary motion. A springy latching ring 32 engaging a groove of stem 27 holds wheel 30 axially in place on the square portion 31.

FIGS. 1 and 4 show that the inner portion of stem 27 is wholly pivoted within member 20. Stem 27 has three axial working positions which are determined by a ball 33 set under the action of a spring 34 and cooperating with three grooves 35, 36 and 37 of stem 27. In the position represented in the drawing, stem 27 is fully pushed into member 20. Ball 33 engages the outer groove 35. Clutch wheel 30 is removed from pinion 26 and the inner end 38 of stem 27 actuates a manually operable switch disclosed hereinafter of the alarm device so as to interrupt the control circuit of that device and to stop the alarm. When the stem 27 is, on the contrary, pulled in its outmost position in which ball 33 engages groove 37, the two crown toothings of clutch wheel 30 and pinion 26, respectively, are in meshing relation so that the rotary motion of the setting stem 27 is transmitted to the alarm hand 11. Finally, when ball 33 engages groove 36, the setting stem 27 is in its intermediate position in which neither its inner end 38 nor the clutch wheel 30 are operative. That intermediate position of the setting stem 27 is that in which the alarm device of the watch described is ready to operate as soon as the watch hands 9, 10 will indicate the same time as the alarm hand 11. Even if the setting stem 27 is inadvertently rotated in that intermediate axial position, the previously set position of the alarm hand is not disturbed. A crown 39 fixed at the outer end of stem 27, which extends throughout tube 40 secured to member 20, permits the setting stem 27 to be actuated manually from outside the watch case.

FIG. 4 shows that the manually operable switch controlled by the end 38 of stem 27, on the one hand, and that the pinion 26 and the clutch wheel 30, on the other hand, each extends within recesses 41, 42, respectively, of member 20, said recesses being opened on the side of the dial 6, but closed on the side of the bottom 43 of the watch case. FIG. 3 shows that the recess 22 provided for the movement 1 is in the same way only open on the dial side. The three recesses 22, 41 and 42 are communicating. The space in which they open is, however, tightly closed by the watch glass 44. For that purpose, the glass 44 which is circular is provided with a peripheral flange 45 lying on a watertight gasket 46 accommodated around the dial 6 within recess 25 of member 20. The latter, which has a shape similar to that of the watch case, is set in a sidewall 47 made integral with the bottom 43. A U-shaped cutout 48 (FIG. 4) is provided in this sidewall 47 for the tube 40 provided for the passage of stem 27. The flange 45 of glass 44 is pressed onto the gasket 46 by means of a bezel 49 made integral with a sidewall also provided with a U-shaped cutout 50 for the passage of tube 40. Projections 51 of the lower case section (43, 47) engaging corresponding recesses provided in the inner surface of the sidewall made integral with the bezel 49, ensure the axial fixation of the two pieces of the watch case to each other, while notches 52 provided in the corners of the lower piece (43,47) ensure opening the casing by engaging a sharp tool in said notches.

As shown in FIG. 1 the winding and hand-setting stem 53 of the watch movement 1 extends in parallel to the alarm-setting stem 27. Stem 53 extends throughout a radial bore of member 20 and its outer portion passes through a tube 54 secured to member 20. A control crown 55 similar to crown 39 is fixed to the outer end of stem 53. As for tube 40 the two watch case pieces (43, 47) and 49 are similarly provided with U-shaped cutouts for tube 54.

In order that the passages of stems 27 and 53 through member 20 do not disturb the tightness of the space comprised between that member and the glass 44 in which the watch movement 1 is enclosed, watertight gaskets need only be provided between the crowns 39 and 55 and the corresponding tubes as it is well known to those skilled in the art.

Member 20, furthermore, carries the different parts of the alarm device of the watch described. These parts chiefly comprise a buzzer which is housed outside the space enclosing the watch movement 1. For that purpose, member 20 is provided with a recess 56 (FIG. 3) opened only on the side of the watch case bottom 43, but closed on the side of the dial 6. Member 20 is, moreover, provided with a recess 57 similar to recess 56 for the battery 58 serving as a source of energy for feeding the alarm device of the watch. As recess 56, recess 57 is also provided outside the space enclosing the movement 1. Recess 57 is only open on the side of the bottom 43.

The buzzer of the alarm device of the watch described comprises a plate 59 (FIG. 3) made out of a ferromagnetic material and located on the bottom of recess 56. A core 60 also made out of a ferromagnetic material is secured to plate 59. Two permanent magnets 61 (FIG. 1) having a parallelepipedic shape are located on plate 59 near the ends thereof within recess 56. The height of magnets 61 is equal to that of the portion of core 60 extending above plate 59. The buzzer, moreover, comprises a plastic body member 62 which is located within recess 56 on the side of plate 59 and which is flush with the lower surface of encasing member 20. Body member 62 carries the electrical members controlling the operation of the buzzer. These members comprise a transistor 63 and a resistor 64 both embedded in body member 62, as well as two coils 65, 66 which are rigidly fixed to body member 62 by gluing and extend around core 60 between magnets 61 FIGS. 1, 3). Coils 65 and 66 are connected to the input and the output circuits, respectively, of transistor 63 which produces an oscillation as soon as its input lead 67 and its output lead 68 are connected to an electrical potential.

The leads 67 and 68 of that oscillator can be connected to terminals being flush with the body member 62 by passing across member 20 without jeopardizing the tight closure ensured by this member. Said leads start from a plate 69 (FIG. 1) which extends within a recess 70 provided in the upper surface of member 20, a portion of leads 67 and 68 being printed on the upper surface of plate 69 made out of an insulating material.

To retain the magnets 61 and core 62 in place within recess 56, a frame member 71 made out of an amagnetic material and extending above magnets 61 and coils 65, 66, is secured at its two ends to member 20 by means of two screws 72. The latter, moreover, serve to fix a spring blade 73 at its two ends above frame member 71 so that blade 73 extends above magnets 61, coils 65, 66 and core 60. A ferromagnetic armature 74 is secured to blade 73 and it extends within frame member 71, however, without coming in contact either with magnets 61 or with core 60.

As soon as the leads 67 and 68 are connected to an electrical potential, the current oscillations produced by the transistor 63 in the coils 65 and 66 cause the armature 74 to be periodically attracted thus causing the blade 73 to vibrate at a natural frequency which can range between 600 and 900 Hz.

Blade 73 is formed in its central portion with a projection 75 striking against a conical plastic membrane 76 which produces an audible sound as soon as the transistorized oscillator operates. Membrane 76 is made with a peripheral flat flange secured for instance by gluing to a threaded ring 77 screwed into a tapped opening 78 of the watch case bottom 43. The outer surface of ring 77 is provided with holes 79 which can be engaged by an appropriate tool for screwing or unscrewing ring 77 in opening 78. A perforated cover member 80 having a threaded rim portion is screwed into opening 78 above ring 77. Cover member 80 protects membrane 76 by preventing foreign bodies from coming in contact with the membrane and tearing the same. The bores provided in cover member 80 provide for the exposition to the atmosphere of membrane 76, thus allowing a free propagation of the sounds produced by that membrane.

To obtain a convenient striking action of the projection 75 of blade 73 against membrane 76, the apex of the latter must be set in a very precise position with respect to blade 73. This apex can be set in the correct position by screwing more or less ring 77 carrying membrane 76 within opening 78. That setting operation is carried out when the watch case is definitely closed. That setting operation is made possible, because ring 77 is accessible from outside the casing after having removed cover member 80. In order to set the membrane 76 in the correct position, the workman entrusted with that operation need only cause the buzzer to operate. He will then be guided by the quality of the sounds produced by the membrane. When these sounds reach an optimum of quality, the cover member 80 can be set in place again where it will serve as a locknut for ring 77.

To prevent the perspiration from entering the buzzer by passing through the threads of opening 78 and of ring 77, a watertight gasket 81 is located under ring 77 and, in the position in which membrane 76 will finally be set, it compresses more or less gasket 81 on a shoulder of bottom 43. Gasket 81 will ensure the tight closure of the buzzer whichever the position of membrane 76 may be, because of its cross section which permits the gasket to be deformed to a relatively large extent.

The watertightness of the watch described does, however, not allow submitting the watch to the same tests as the usual watertight watches. If the watch described were submitted to an overpressure of several atmospheres, the membrane 76 would be torn. That membrane, however, perfectly resists to overpressures reaching 1 atu and even somewhat more.

The space of the watch case in which the buzzer is accommodated could also be made watertight in the same manner as the space occupied by the watch movement 1. For that purpose a watertight gasket similar to gasket 46 needed only be inserted between the encasing member 20 and the watch case bottom 43.

It will be observed that if membrane 76 were incidentally torn, no damage would result therefrom for the watch movement 1. The space occupied by the buzzer would be immersed alone. If such an immersion injured the buzzer, the latter could merely be replaced and the watch would be restored into its original state.

The battery 58 can be replaced without opening the watch case. The bottom 43 is therefore provided with an opening 82 coaxial to recess 57 of member 20. Opening 82 is closed by means of a bush 83 screwed into member 20. A slot 84 enables screwing bush 83. It has already been indicated hereabove that the recess 57 provided in member 20 for the battery 58 does not communicate with the space within which the watch movement 1 is located. If the battery 58 leaked or produced corrosive emanations, the movement 1 would not be injured. To avoid an immersion of the space housing battery 58, a gasket 85 is inserted between two shoulders of the bush 83 and the bottom 43, respectively.

The positive pole of battery 58 consisting of a cap 86 is electrically connected to the ground mass of the watch by means of bush 84. As regards the negative pole 87 of the battery, it is in contact with a stud 88 held in place in a bore of member 20 by means of a screw 89. The passage of stud 88 through member 20 is tightly closed by means of a sleeve 90 which could at the same time insulate the stud if member 20 were made of a conducting material.

Screw 89 also serves as a fixing means securing to member 20 one of the two arms 91, 92 made integral with plate 69 carrying a printed circuit. In addition to the portions of leads 67 and 68 described hereabove this printed circuit still comprises two conductors 93 and 94 (FIG. 1). Conductor 93 firstly extends along arm 91 and then over plate 69 so as to connect the negative pole of battery 58 to the lead 68 of the buzzer. The conductor 94 in turn also extends over a portion of plate 69 and then along arm 92 and it is connected at its end to a stud 95 secured to arm 92 and made integral with a cam 96 (FIG. 4). Arm 92 is bent out of the plane of plate 69 thus causing stud 95 to bear normally against the dial 6 thus establishing an electrical connection between these two members which constitute the terminals of a manually operable switch provided for stopping the alarm at will. In the position represented in the drawing that switch is opened by means of stem 27 which is in its innermost position. In that position the inner end 38 of the stem engages cam 96 and holds stud 95 remote from dial 6.

If, in a modification of the embodiment represented in the drawing, the conductor 94 were directly connected to lead 67 on the printing circuit 69, the control circuit of the electrical alarm device of the watch described would be established from the negative pole 87 of battery 58 through conductor 93 to the buzzer, from the buzzer through conductors 67 and 94 to the switch (6, 95), from that switch through the dial 6 to the switch 2 driven by the watch movement and, finally, from switch 2 through the ground mass to the positive pole 86 of battery 58.

In the embodiment represented in the drawing the conductor 94 is, however, not directly connected to lead 67 of the buzzer; an electronic interrupter 97 (FIG. 1) constituted by a transistor, the base of which is biased by a flip-flop, is inserted between these two conductors. Interrupter 97 has three terminals: 98, to which lead 68 and conductor 93 are connected; 99, to which lead 67 is connected, and 100, to which conductor 94 is connected.

Interrupter 97 causes the alarm device of the watch described to produce an interrupted sound. With the help of that interrupter the watchmaker can at will produce either short interruptions of the sound following each other at more or less long time intervals, or cause membrane 76 to vibrate only during very short time periods at more or less spaced times.

As shown in FIGS. 1 and 2, interruptor 97 is located under plate 69 within a recess 101 of member 20.

It should be understood that the watch could also comprise a circular movement instead of that represented in the drawing. Moreover, that movement could, of course, be equipped with a self-winding mechanism.

In spite of the location described for the buzzer and the battery at the corners of the watch case, the latter can be bevelled at its periphery in the same manner as the usual flat watches, because these two members of the alarm device can be made with very small sizes.

The watch according to the second embodiment (FIG. 5) differs from that of the first embodiment solely by the fact that its casing does not comprise a separate encasing member. The bottom 102 itself serves as an encasing means for the watch movement. In other words, the two pieces 20 and 43 of the first embodiment are in the second one replaced by the single member 102.

The third embodiment (FIG. 6) in turn differs from the second one by the fact that the buzzer is no longer mounted directly in the watch case member 102 but in a capsule 103.

The input and output leads 67a, 68a of the buzzer extend across the walls of capsule 103 and are connected to sockets 104, 105 constituting the female terminals of an electrical plug.

If capsule 103 is made of plastic, the leads 67a, 68a can simply be embedded in the mass of the capsule.

Capsule 103 can be set as a unit in recess 106 of the watch case member 102a. The necessary electrical connections between leads 67a, 68a and the other circuit elements (battery, switches) are established through the male terminals 107, 108 carried by member 102a and corresponding to sockets 104, 105 of capsule 103. In the third embodiment member 102a and capsule 103 can advantageously be plastic moulded pieces.

In a modification it would also be possible to locate the different members of the buzzer, not in a capsule having a cylindrical shape, but in an envelope having a thin wall and a shape adapted to the geometry of the buzzer. The third embodiment has the advantage that the buzzer is easily removable from the watch. In the event of a defect or an injury, the watch carrier can replace the buzzer himself.

Claims

I claim:

1. A watertight alarm wristwatch comprising, in combination, a watch case having a bottom provided with an opening, a watch movement located in said watch case, an alarm device having all its parts located in said watch case and including an electrodynamic transducer, a resilient member and a membrane, said membrane extending across said opening of the watch case bottom and producing the audible sounds of the alarm device under the mechanical action of said resilient member when the latter is vibrating at a natural frequency, said electrodynamic transducer being arranged for causing said resilient member to vibrate at a natural frequency and for entertaining that vibration, and an envelope included by said watch case, for isolating a part of the alarm device from the watch movement, said envelope comprising a section provided with a recess having its opening exclusively directed toward the watch case bottom away from the space occupied by said movement, said recess forming at least a part of a housing arranged for the accommodation of at least said resilient member of said alarm device.

2. A watertight alarm wristwatch according to claim 1, in which said envelope section includes the watch case bottom, a first recess being provided in the inner surface of said section for said watch movement, and a second recess being provided in the outer surface of said section for said resilient member of the alarm device.

3. A watertight alarm wristwatch according to claim 1, in which a capsule includes all the parts of the alarm device with the exception of the source of energy and of control switches, said capsule being tightly closed by said membrane and located in a recess provided in the watch case bottom.

4. A watertight alarm wristwatch according to claim 1, in which said envelope section consists of an encasing member having a first recess provided in one of its side surfaces for said watch movement and a second recess provided in its opposed side surface for said resilient member of the alarm device, an annular watertight gasket located between said envelope section and a watch case part including the watchglass tightly closing said envelope.

5. A watertight alarm wristwatch according to claim 4, in which a further watertight gasket is located between said envelope section and a watch case part including the watch case bottom, thereby tightly closing the housing of said resilient member.

6. A watertight alarm wristwatch according to claim 4, in which a third recess is provided in said envelope section in the same side surface thereof as said second recess, said third recess serving as a housing for an electrical source of energy forming part of said alarm device.